A plasmid found in the yeast Saccharomyces cerevisiae and used as the basis for a series of cloning vectors.

A base analog that can cause mutations by replacing adenine in a DNA molecule.

A component of the bacterial promoter.

The end of a polynucleotide that terminates with a hydroxyl group attached to the 3′-carbon of the sugar.

Transfer of a segment of genomic DNA from one place to another caused by movement of a LINE element.

The untranslated region of an mRNA downstream of the termina-tion codon.

A relatively unpacked form of chromatin consisting of a possibly helical array of nucleosomes in a fiber approximately 30 nm in diameter.

A base analog that can cause mutations by replacing thymine in a DNA molecule.

The end of a polynucleotide that terminates with a mono-, di- or triphosphate attached to the 5′-carbon of the sugar.

The untranslated region of an mRNA upstream of the initiation codon.

A dimer between two adjacent pyrimidine bases in a polynucleotide, formed by ultraviolet irradiation.

An enzyme involved in photoreactivation repair.

One of the commonest secondary structural conformations taken up by segments of polypeptides.

The linkage between the base and sugar of a nucleotide.

One of the commonest secondary structural conformations taken up by segments of polypeptides.

A sequence of four amino acids, the second usually glycine, which causes a polypeptide to change direction.

A component of DNA polymerase III comprising subunit γ in association with δ, δ′, χ and ψ.

A type of RNA-binding domain.

The hydrophobic interactions that occur between adjacent base pairs in a double-stranded DNA molecule.

Part of the structure of a tRNA molecule.

The splice site at the 3′ end of an intron.

A type of activation domain.

A chemical compound that causes a frameshift mutation by intercalating between adjacent base pairs of the double helix.

The part of an activator that makes contact with the initiation complex.

A DNA-binding protein that stabilizes construction of the RNA polymerase II transcription initiation complex.

The attachment of a lipid sidechain to a polypeptide.

An Escherichia coli enzyme that is involved in the direct repair of alkylation mutations.

A synthetic, double-stranded oligonucleotide used to attach sticky ends to a blunt-ended molecule.

A purine base found in DNA and RNA.

An enzyme that edits various eukaryotic mRNAs by deaminating adenosine to inosine.

The enzyme that converts ATP to cyclic AMP.

A structural configuration of the double helix, present but not common in cellular DNA.

A column chromatography method that makes use of a ligand that binds to the molecule being purified.

Electrophoresis carried out in an agarose gel and used to separate DNA molecules between 100 bp and 50 kb in length.

An enzyme that removes phosphate groups from the 5′ ends of DNA molecules.

A mutagen that acts by adding alkyl groups to nucleotide bases.

One of two or more alternative forms of a gene.

The frequency of an allele in a population.

The use of an oligonucleotide probe to determine which of two alternative nucleotide sequences is contained in a DNA molecule.

A polyploid nucleus derived from fusion between gametes from different species.

The tandemly repeated nucleotide sequences located in the centromeric regions of human chromosomes.

The production of two or more mRNAs from a single pre-mRNA by joining together different combinations of exons.

A type of SINE found in the genomes of humans and related mammals.

A clone fingerprinting technique that uses PCR to detect the relative positions of Alu sequences in cloned DNA fragments.

One of the monomeric units of a protein molecule.

The end of a polypeptide that has a free amino group.

The site in the ribosome occupied by the aminoacyl-tRNA during translation.

Attachment of an amino acid to the acceptor arm of a tRNA.

An enzyme that catalyzes the aminoacylation of one or more tRNAs.

A character state possessed by a remote common ancestor of a group of organisms.

DNA preserved in ancient biological material.

Attachment of an oligonucleotide primer to a DNA or RNA template.

The triplet of nucleotides, at positions 34–36 in a tRNA molecule, that base-pairs with a codon in an mRNA molecule.

Part of the structure of a tRNA molecule.

A substance that elicits an immune response.

A bacterial mechanism for regulating the termination of transcription.

A protein that attaches to bacterial DNA and mediates anti-termination.

A position in a DNA molecule where the base component of the nucleotide is missing.

An enzyme involved in base excision repair.

A character state that evolved in a recent ancestor of a subset of organisms in a group being studied.

Programmed cell death.

One of the two main groups of prokaryotes, mostly found in extreme environments.

One of the haploid products of meiosis in an ascomycete such as the yeast Saccharomyces cerevisiae.

The structure which contains the four ascospores produced by a single meiosis in the yeast Saccharomyces cerevisiae.

A process used by some bacteria to regulate expression of an amino acid biosynthetic operon in accordance with the levels of the amino acid in the cell.

A type of intron found in eukaryotic nuclear genes: the first two nucleotides in the intron are 5′–AU–3′ and the last two are 5′–AC–3′.

A DNA sequence, particularly from yeast, that confers replicative ability on a non-replicative plasmid.

A polyploid nucleus derived from fusion of two gametes from the same species, neither of which is haploid.

The detection of radioactively labeled molecules by exposure of an X-ray-sensitive photographic film.

A chromosome that is not a sex chromosome.

A mutant microorganism that can grow only when supplied with a nutrient that is not needed by the wild type.

A chromosome possessed by some individuals in a population, but not all.

One of the two main groups of prokaryotes.

A high-capacity cloning vector based on the F plasmid of Escherichia coli.

A virus that infects a bacterium.

A high-capacity cloning vector based on bacteriophage P1.

The highly condensed chromatin structure taken up by an inactivated X chromosome.

The position within a eukaryotic promoter where the initiation complex is assembled.

Sequence motifs that are present in many eukaryotic promoters and set the basal level of transcription initiation.

The number of productive initiations of transcription occurring per unit time at a particular promoter.

A compound whose structural similarity to one of the bases in DNA enables it to act as a mutagen.

A DNA repair process that involves excision and replacement of an abnormal base.

The hydrogen-bonded structure formed by two complementary nucleotides. When abbreviated to ‘bp’, the shortest unit of length for a double-stranded DNA molecule.

The ratio of A to T, or G to C, in a double-stranded DNA molecule. Chargaff showed that the base ratios are always close to 1.0.

A position in a DNA molecule where the base component of the nucleotide is missing.

The attachment of one polynucleotide to another, or one part of a polynucleotide to another part of the same polynucleotide, by base pairs.

The hydrophobic interactions that occur between adjacent base pairs in a double-stranded DNA molecule.

A type of DNA-binding domain.

The commonest structural conformation of the DNA double helix in living cells.

An unpacked form of chromatin consisting of nucleosome beads on a string of DNA.

The use of computer methods in studies of genomes.

A means of introducing DNA into cells that involves bombardment with high-velocity microprojectiles coated with DNA.

The information contained in the genome of an organism and which directs the development and maintenance of that organism.

The use of living organisms, often, but not always microbes, in industrial processes.

Attachment of a biotin label to a DNA or RNA molecule.

The structure formed when a pair of homologous chromosomes lines up during meiosis.

An end of a double-stranded DNA molecule where both strands terminate at the same nucleotide position with no single-stranded extension.

A method for inferring the degree of confidence that can be assigned to a branch point in a phylogenetic tree.

The statistical value obtained by bootstrap analysis.

A temporary reduction in the size of a population.

A component of a phylogenetic tree.

A step in the Holliday model for homologous recombination, involving exchange of polynucleotides between a pair of recombining double-stranded DNA molecules.

The density possessed by a molecule or particle when suspended in an aqueous salt or sugar solution.

The end of a polypeptide that has a free carboxyl group.

A basal promoter element.

The chemical modification at the 5′ end of most eukaryotic mRNA molecules.

The complex that makes the initial attachment to the cap structure at the beginning of the scanning phase of eukaryotic translation.

A DNA-binding site for the catabolite activator protein.

Attachment of a cap to the 5′ end of a eukaryotic mRNA.

The protein coat that surrounds the DNA or RNA genome of a virus.

The end of a polypeptide that has a free carboxyl group.

Proteins thought to play regulatory roles during splicing of GU–AG introns.

A regulatory protein that binds to various sites in a bacterial genome and activates transcription initiation at downstream promoters.

The means by which extracellular glucose levels dictate whether genes for sugar utilization are switched on or off in bacteria.

A double-stranded DNA copy of an mRNA molecule.

Repeated hybridization probing of a pool of cDNAs with the objective of obtaining a subpool enriched in certain sequences.

The series of events occurring in a cell between one division and the next.

A period before entry into S or M phase of the cell cycle, a key point at which regulation is exerted.

The period in a cell lineage when the cells are alive but no longer able to divide.

A cell extract containing all the components needed for protein synthesis and able to translate added mRNA molecules.

Sequence motifs present in the promoters of eukaryotic genes that are expressed in just one type of tissue.

The constricted region of a chromosome that is the position at which the pair of chromatids are held together.

A DNA sequencing method that involves enzymatic synthesis of polynucleotide chains that terminate at specific nucleotide positions.

A multi-subunit protein that forms a structure that aids the folding of other proteins.

One of at least two alternative forms of a character used in phylogenetic analysis.

A DNA sequencing method that involves the use of chemicals that cut DNA molecules at specific nucleotide positions.

The change in the rotation of a chemical nucleus, used as the basis of NMR.

An intermediate structure seen during recombination between DNA molecules.

A repeated nucleotide sequence in the Escherichia coli genome that is involved in the initiation of homologous recombination.

An organism composed of two or more genetically different cell types.

One of the photosynthetic organelles of a eukaryotic cell.

The genome present in the chloroplasts of a photosynthetic eukaryotic cell.

The arm of a chromosome.

The complex of DNA and histone proteins found in chromosomes.

A subcomponent of chromatin made up of a nucleosome core octamer with associated DNA and a linker histone.

One of the DNA–protein structures that contains part of the nuclear genome of a eukaryote. Less accurately, the DNA molecule(s) that contain(s) a prokaryotic genome.

A component of the nuclear matrix which changes its structure during cell division, resulting in condensation of the chromosomes into their metaphase forms.

The theory, first propounded by Sutton in 1903, that genes lie on chromosomes.

A technique that can be used to construct a clone contig by identifying overlapping fragments of cloned DNA.

Movement of a nucleosome to a new position on a DNA molecule.

A group of monophyletic organisms or DNA sequences that include all of those in the analysis that are descended from a particular common ancestor.

A phylogenetic approach that stresses the importance of understanding the evolutionary relevance of the characters that are studied.

A protein that plays an ancillary role during polyadenylation of eukaryotic mRNAs.

A protein that plays an ancillary role during polyadenylation of eukaryotic mRNAs.

A group of cells that contain the same recombinant DNA molecule.

A collection of clones whose DNA fragments overlap.

A genome sequencing strategy in which the molecules to be sequenced are broken into manageable segments, each a few hundred kb or few Mb in length, which are sequenced individually.

Any one of several techniques that compare cloned DNA fragments in order to identify ones that overlap.

A collection of clones, possibly representing an entire genome, from which individual clones of interest are obtained.

A DNA molecule that is able to replicate inside a host cell and therefore can be used to clone other fragments of DNA.

The structure formed during the initial step in assembly of the transcription initiation complex. The closed promoter complex consists of the RNA polymerase and/or accessory proteins attached to the promoter, before the DNA has been opened up by breakage of base pairs.

A two-dimensional representation of the structure of a tRNA molecule.

A protein that works in conjunction with an activator to stabilize construction of the RNA polymerase II transcription initiation complex.

An RNA molecule that codes for a protein; an mRNA.

The relationship between a pair of alleles which both contribute to the phenotype of a heterozygote.

A triplet of nucleotides coding for a single amino acid.

The interaction between a codon on an mRNA molecule and the corresponding anticodon on a tRNA.

Refers to the fact that not all codons are used equally frequently in the genes of a particular organism.

The protein that holds sister chromatids together during the period between genome replication and nuclear division.

An end of a double-stranded DNA molecule where there is a single-stranded extension.

An intermediate in the pathway resulting in replicative transposition.

The initial structure formed during splicing of a GU–AG intron.

A research strategy that uses information obtained from the study of one genome to make inferences about the map positions and functions of genes in a second genome.

Refers to a culture of bacteria that have been treated, for example, by soaking in calcium chloride, so that their ability to take up DNA molecules is enhanced.

Refers to two nucleotides or nucleotide sequences that are able to base-pair with one another.

A double-stranded DNA copy of an mRNA molecule.

A DNA transposon comprising a pair of insertion sequences flanking a segment of DNA usually containing one or more genes.

A DNA molecule made up of linear genomes or other DNA units linked head to tail.

The evolutionary process that results in the members of a multigene family retaining the same or similar sequences.

A mutation that results in a cell or organism able to survive only under permissive conditions.

Transfer of DNA between two bacteria that come into physical contact with one another.

A technique for mapping bacterial genes by determining the time it takes for each gene to be transferred during conjugation.

A nucleotide sequence that represents an ‘average’ of a number of related but non-identical sequences.

A hypothetical mode of DNA replication in which one daughter double helix is made up of the two parental polynucleotides and the other is made up of two newly synthesized polynucleotides.

Transposition that does not result in copying of the transposable element.

Control over bacterial gene expression that depends on the sequence of the promoter.

Chromatin that is permanently in a compact organization.

A mutation that results in continuous expression of a gene or set of genes that is normally subject to regulatory control.

Refers to the situation whereby the DNA sequence surrounding a codon changes the meaning of that codon.

A contiguous set of overlapping DNA sequences.

An electrophoresis method used to separate large DNA molecules.

A gene that has become inactive because of the accumulation of mutations.

The situation that occurs when the same character state evolves independently in two lineages.

The version of Escherichia coli RNA polymerase, subunit composition α₂ββ′, that carries out RNA synthesis but is unable to locate promoters efficiently.

The central component of a nucleosome, made up of two subunits each of histones H2A, H2B, H3 and H4, around which DNA is wound.

The position within a eukaryotic promoter where the initiation complex is assembled.

A small molecule that must be bound to a repressor protein before the latter is able to attach to its operator site.

One of the cohesive, single-stranded extensions present at the ends of the DNA molecules of certain strains of λ phage.

A high-capacity cloning vector consisting of the λ cos site inserted into a plasmid.

Transfer of two or more genes from one bacterium to another via a transducing phage.

Uptake of two or more genes on a single DNA molecule during transformation of a bacterium.

A GC-rich DNA region located upstream of approximately 56% of the genes in the human genome.

An important transcription factor.

The exchange of DNA between chromosomes during meiosis.

A site whose sequence resembles an authentic splice site and which might be selected instead of the authentic site during aberrant splicing.

One of several genes in the trypanosome mitochondrial genome which specify abbreviated RNAs that must undergo pan-editing in order to become functional.

A type of protein thought to play a regulatory role during splicing of GU–AG introns.

A component of the largest subunit of RNA polymerase II, important in activation of the polymerase.

The non-equivalence between genome size and gene number that is seen when comparisons are made between some eukaryotes.

A photosynthetic organelle that resembles an ingested cyanobacterium.

A modified version of AMP in which an intramolecular phosphodiester bond links the 5′ and 3′ carbons.

A regulatory protein whose abundance varies during the cell cycle and which regulates biochemical events in a cell-cycle-specific manner.

A dimer between two adjacent pyrimidine bases in a polynucleotide, formed by ultraviolet irradiation.

A type of zinc-finger DNA-binding domain.

The use of compound-specific stains, combined with microscopy, to determine the biochemical content of cellular structures.

One of the pyrimidine bases found in DNA and RNA.

Part of the structure of a tRNA molecule.

A type of nucleotide excision repair process that corrects cyclobutyl dimers.

Addition of methyl groups to new positions on a DNA molecule.

A process for degradation of eukaryotic mRNAs that is initiated by removal of the poly(A) tail.

A mutagen that acts by removing amino groups from nucleotide bases.

Refers to the fact that the genetic code has more than one codon for most amino acids.

A multienzyme complex responsible for degradation of bacterial mRNAs.

A mutation whose effect is not apparent until a relatively late stage in the life of the mutant organism.

A mutation resulting from deletion of one or more nucleotides from a DNA sequence.

Breakdown by chemical or physical means of the non-covalent interactions, such as hydrogen bonding, that maintain the secondary and higher levels of structure of proteins and nucleic acids.

A technique in which a cell fraction is centrifuged through a dense solution, in the form of a gradient, so that individual components are separated.

An enzyme that cleaves phosphodiester bonds in a DNA molecule.

A character state that evolved in a recent ancestor of a subset of organisms in a group being studied.

A coordinated series of transient and permanent changes that occurs during the life history of a cell or organism.

The phenomenon whereby a bacterium, when provided with a mixture of sugars, uses up one sugar before beginning to metabolize the second sugar.

The ribonuclease that plays a central role in RNA interference.

A modified nucleotide that lacks the 3′ hydroxyl group and so terminates strand synthesis when incorporated into a polynucleotide.

A technique that separates cell components by centrifuging an extract at different speeds.

The production of two or more mRNAs from a single pre-mRNA by joining together different combinations of exons.

The adoption by a cell of a specialized biochemical and/or physiological role.

A sexual cross in which the inheritance of two pairs of alleles is followed.

A protein or other structure that comprises two subunits.

A nucleus that has two copies of each chromosome.

The recognition of a DNA sequence by a binding protein that makes contacts with the outside of a double helix.

A DNA repair system that acts directly on a damaged nucleotide.

A nucleotide sequence that is repeated twice or more frequently in a DNA molecule.

A set of experimental techniques that is used to obtain novel genes with improved products.

A gene that is split into exons and introns.

A hypothetical mode of DNA replication in which both polynucleotides of each daughter double helix are made up partly of parental DNA and partly of newly synthesized DNA.

A mode of replication which involves continuous copying of one strand of the helix, the second strand being displaced and subsequently copied after synthesis of the first daughter strand has been completed.

A table showing the evolutionary distances between all pairs of nucleotide sequences in a dataset.

A rigorous mathematical approach to alignment of nucleotide sequences.

A covalent bond linking cysteine amino acids on different polypeptides or at different positions on the same polypeptide.

An intermediate structure formed during the Meselson–Radding model for homologous recombination. Also an intermediate formed during displacement replication.

Deoxyribonucleic acid, one of the two forms of nucleic acid in living cells; the genetic material for all cellular life forms and many viruses.

An enzyme involved in methylation of Escherichia coli DNA.

A type of conformational change introduced into a DNA molecule by a binding protein.

The part of a DNA-binding protein that makes contact with the double helix.

A protein that attaches to a DNA molecule.

A high-density array of DNA molecules used for parallel hybridization analyses.

Insertion of a fragment of DNA into a cloning vector, and subsequent propagation of the recombinant DNA molecule in a host organism.

An enzyme involved in methylation of Escherichia coli DNA.

An enzyme that makes a DNA copy of a DNA template.

An enzyme that makes an RNA copy of a DNA template.

An enzyme that cleaves the β-N-glycosidic bond between a base and the sugar component of a nucleotide as part of the base excision and mismatch repair processes. The name is a misnomer and should be DNA glycolyase, but the incorrect usage is now embedded in the literature.

A Type II topoisomerase of Escherichia coli.

An enzyme that synthesizes phosphodiester bonds as part of DNA replication, repair and recombination processes.

A DNA sequence that exists as two or more readily distinguished versions and which can therefore be used to mark a map position on a genetic, physical or integrated genome map.

Refers to the chemical modification of DNA by attachment of methyl groups.

An enzyme that attaches methyl groups to a DNA molecule.

A bacterial enzyme involved in photoreactivation repair.

An enzyme that synthesizes DNA.

The enzyme that primes DNA replication in eukaryotes.

The main eukaryotic DNA replicating enzyme.

The enzyme responsible for replication of the mitochondrial genome.

The bacterial enzyme that completes synthesis of Okazaki fragments during genome replication.

A bacterial DNA polymerase involved in DNA repair.

The main DNA replicating enzyme of bacteria.

The biochemical processes that correct mutations arising from replication errors and the effects of mutagenic agents.

Synthesis of a new copy of the genome.

A short region of eukaryotic DNA that is relatively easily cleaved with deoxyribonuclease I, possibly coinciding with positions where nucleosomes are absent.

The technique for determining the order of nucleotides in a DNA molecule.

A PCR-based procedure that results in directed evolution of a DNA sequence.

An enzyme that introduces or removes turns from the double helix by breakage and reunion of one or both polynucleotides.

A transposon whose transposition mechanism does not involve an RNA intermediate.

A virus with a DNA genome, able to cause cancer after infection of an animal cell.

A segment of a polypeptide that folds independently of other segments; also the segment of a gene coding for such a domain.

Duplication of a gene segment coding for a structural domain in the protein product.

Rearrangement of segments of one or more genes, each segment coding for a structural domain in the gene product, to create a new gene.

The allele that is expressed in a heterozygote.

The splice site at the 5′ end of an intron.

A method for aligning nucleotide sequences.

The base-paired double-stranded structure that is the natural form of DNA in the cell.

A nucleus that is heterozygous for two genes.

A nucleus that is homozygous for two genes.

Digestion of DNA with two restriction endonucleases at the same time.

A DNA repair process that mends double-stranded breaks.

Comprising two polynucleotides attached to one another by base-pairing.

A common type of RNA-binding domain.

Towards the 3′ end of a polynucleotide.

A solution hybridization technique used to type SNPs.

A position within a bacterial ribosome to which a tRNA moves immediately after deacylation.

Separation of molecules on the basis of their net electrical charge.

Ionic bonds that form between charged chemical groups.

A protein that plays an ancillary role in the elongation step of transcription or translation.

A yeast protein, possibly with histone acetyltransferase activity, involved in the elongation phase of transcription.

A totipotent cell from the embryo of a mouse or other organism.

The attachment of a radioactive or other label to one end of a DNA or RNA molecule.

The chemical alteration of the end of a DNA or RNA molecule.

An enzyme used in recombinant DNA technology that alters the chemical structure at the end of a DNA molecule.

An active or inactive retroviral genome integrated into a host chromosome.

An enzyme that breaks phosphodiester bonds within a nucleic acid molecule.

A theory that states that the mitochondria and chloroplasts of eukaryotic cells are derived from symbiotic prokaryotes.

A structure formed by DNA bending that comprises a collection of proteins involved in activation of the RNA polymerase II transcription initiation complex.

A regulatory sequence that increases the rate of transcription of a gene or genes located some distance away in either direction.

A plasmid that is able to integrate into the host cell’s chromosome.

Transfer between cells of some or all of a bacterial chromosome by integration into a plasmid.

A type of intercalating agent that causes mutations by inserting between adjacent base pairs in a double-stranded DNA molecule.

A mutagen that acts by adding alkyl groups to nucleotide bases.

Regions of a eukaryotic chromosome that are relatively uncondensed, thought to contain active genes.

An organism whose cells contain membrane-bound nuclei.

A DNA repair process that corrects various types of DNA damage by excising and resynthesizing a region of polynucleotide.

A position within a bacterial ribosome to which a tRNA moves immediately after deacylation.

A coding region within a discontinuous gene.

A nucleotide sequence that plays a positive regulatory role during splicing of GU–AG introns.

A nucleotide sequence that plays a negative regulatory role during splicing of GU–AG introns.

The nucleotide sequence at the junction between an exon and an intron.

Aberrant splicing in which one or more or exons are omitted from the spliced RNA.

An ‘introns early’ hypothesis that holds that introns were formed when the first DNA genomes were constructed.

A method, based on cloning, for identifying the positions of exons in a DNA sequence.

An enzyme that removes nucleotides from the ends of a nucleic acid molecule.

A multiprotein complex involved in degradation of mRNA in eukaryotes.

A protein involved in transport of molecules out of the nucleus.

A cDNA that is sequenced in order to gain rapid access to the genes in a genome.

The functional component of a discontinuous protein.

The end of a branch in a phylogenetic tree, representing one of the organisms or DNA sequences being studied.

A gene in a mitochondrial or chloroplast genome.

A fertility plasmid that directs conjugal transfer of DNA between bacteria.

Chromatin that has a compact organization in some, but not all cells, thought to contain genes that are inactive in some cells or at some periods of the cell cycle.

The ‘flap endonuclease’ involved in replication of the lagging strand in eukaryotes.

A specialized form of FISH that enables high marker resolution.

An electrophoresis method used to separate large DNA molecules.

The ability of an organism or allele to survive and reproduce.

Refers to the situation that occurs when a single allele reaches a frequency of 100% in a population.

A method for the separation of chromosomes.

The unit used in FISH to describe the position of a hybridization signal relative to the end of the short arm of the chromosome.

A technique used to study the mobility of nuclear proteins.

A technique for locating markers on chromosomes by observing the hybridization positions of fluorescent labels.

An end of a double-stranded DNA molecule where both strands terminate at the same nucleotide position with no single-stranded extension.

N-formylmethionine, the modified amino acid carried by the tRNA that is used during the initiation of translation in bacteria.

A segment of a polypeptide that folds independently of other segments.

The series of events, involving partially folded intermediates, that results in an unfolded protein attaining its correct three-dimensional structure.

A range of techniques used for locating bound proteins on DNA molecules.

A high-capacity vector carrying the F plasmid origin of replication and a λ cos site.

A position in a chromosome that is prone to breakage because it contains an expanded trinucleotide repeat sequence.

A mutation resulting from insertion or deletion of a group of nucleotides that is not a multiple of three and which therefore changes the frame in which translation occurs.

The movement of a ribosome from one reading frame to another at an internal position within a gene.

The area of genome research devoted to identifying the functions of unknown genes.

A region of eukaryotic DNA around a gene or group of genes that can be delineated by treatment with deoxyribonuclease I.

A protein that consists of a fusion of two polypeptides, or parts of polypeptides, normally coded by separate genes.

The first gap period of the cell cycle.

The second gap period of the cell cycle.

A mutation that results in an organism acquiring a new function.

A reproductive cell, usually haploid, that fuses with a second gamete to produce a new cell during sexual reproduction.

A set of proteins that are intermediates in the Ras signal transduction pathway.

Developmental genes that play a role in establishing positional information within the Drosophila embryo.

One of two intermediate periods within the cell cycle.

A type of basal promoter element.

The percentage of nucleotides in a genome that are G or C.

Electrophoresis performed in a gel so that molecules of similar electrical charge can be separated on the basis of size.

A technique that identifies protein-binding sites on DNA molecules by virtue of the effect that a bound protein has on the mobility of the DNA fragments during gel electrophoresis.

A technique for preparing restricted DNA molecules for optical mapping.

A DNA segment containing biological information and hence coding for an RNA and/or polypeptide molecule.

Insertion of a fragment of DNA, containing a gene, into a cloning vector, and subsequent propagation of the recombinant DNA molecule in a host organism.

A process that results in the four haploid products of meiosis displaying an unusual segregation pattern.

The series of events by which the biological information carried by a gene is released and made available to the cell.

The transfer of a gene from one organism to another.

A gene relic consisting of a short isolated region from within a gene.

Recombination between two homologous double-stranded DNA molecules.

A protein or protein complex that is a transient or permanent component of the initiation complex formed during eukaryotic transcription.

The replacement of an allele that at one time was fixed in the population by a second allele, this second allele arising by mutation and increasing in frequency until itself reaching fixation.

A group of two or more evolutionarily related multigene families.

Refers to a gene whose intron contains a second gene.

A clinical procedure in which a gene or other DNA sequence is used to treat a disease.

The rules that determine which triplet of nucleotides codes for which amino acid during protein synthesis.

A technique for the rapid functional analysis of many genes at once.

The physical association between two genes that are on the same chromosome.

The use of genetic techniques to construct a genome map.

A gene that exists as two or more readily distinguished alleles and whose inheritance can therefore be followed during a genetic cross, enabling the map position of the gene to be determined.

The banding pattern revealed after electrophoresis of the products of PCRs directed at a range of microsatellite loci.

The situation that occurs when two genes in the same genome perform the same function.

The branch of biology devoted to the study of genes.

A phylogenetic tree that shows the evolutionary relationships between a group of genes or other DNA sequences.

The entire genetic complement of a living organism.

The series of events by which the biological information carried by a genome is released and made available to the cell.

A sequence that recurs at many dispersed positions within a genome.

Inactivation by methylation of a gene on one of a pair of homologous chromosomes.

A description of the genetic composition of an organism.

1 000 000 kb; 1 000 000 000 bp.

A general down-regulation in protein synthesis that occurs in response to various signals.

A type of activation domain.

The attachment of sugar units to a polypeptide.

A set of proteins that are intermediates in the Ras signal transduction pathway.

A protein that is used to label other proteins and whose gene is used as a reporter gene.

A type of intron found mainly in organelle genes.

A type of intron found in organelle genes.

A type of intron found in organelle genes.

A set of proteins that are intermediates in the Ras signal transduction pathway.

The commonest type of intron in eukaryotic nuclear genes. The first two nucleotides of the intron are 5′–GU–3′ and the last two are 5′–AG–3′.

One of the purine nucleotides found in DNA and RNA.

The enzyme that attaches a methyl group to the 5′ end of a eukaryotic mRNA during the capping reaction.

A set of proteins that are intermediates in the Ras signal transduction pathway.

The enzyme that attaches a GTP to the 5′ end of a eukaryotic mRNA at the start of the capping reaction.

A short RNA that specifies the positions at which one or more nucleotides are inserted into an abbreviated RNA by pan-editing.

An RNA structure with ribozyme activity that is found in some viruses.

A nucleus that has a single copy of each chromosome.

The situation where inactivation of a gene on one of a pair of homologous chromosomes results in a change in the phenotype of the mutant organism.

A collection of alleles that are usually inherited together.

An enzyme that breaks base pairs in a double-stranded DNA molecule.

A dimerization domain commonly found in DNA-binding proteins.

A common structural motif for attachment of a protein to a DNA molecule.

A phage that is introduced into a host cell in conjunction with a related cloning vector, in order to provide enzymes and other proteins required for replication of the cloning vector.

Chromatin that is relatively condensed and is thought to contain DNA that is not being transcribed.

A DNA–DNA or DNA–RNA hybrid.

Transcript mapping by analysis of DNA–RNA hybrids with a single-strand-specific nuclease such as S1.

The nuclear RNA fraction that comprises unprocessed transcripts synthesized by RNA polymerase II.

An artificial RNA comprising a mixture of different nucleotides.

The probability that a person chosen at random from the population will be heterozygous for a particular marker.

A diploid nucleus that contains two different alleles for a particular gene.

A group of nuclear proteins that influence chromatin structure.

A column chromatography method with many applications in biochemistry.

One of the basic proteins found in nucleosomes.

Modification of chromatin structure by attachment of acetyl groups to core histones.

An enzyme that attaches acetyl groups to core histones.

The hypothesis that the pattern of chemical modification on histone proteins influences various cellular activities.

An enzyme that removes acetyl groups from core histones.

An intermediate structure formed during recombination between two DNA molecules.

A chromosome that does not have a single centromere but instead has multiple kinetochores spread along its length.

The version of the Escherichia coli RNA polymerase, subunit composition α₂ββ′σ, that is able to recognize promoter sequences.

A DNA-binding motif found in many proteins involved in developmental regulation of gene expression.

A mutation that results in the transformation of one body part into another.

A gene that establishes the identity of a body part such as a segment of the Drosophila embryo.

Two or more identical chromosomes present in a single nucleus.

Genes that share a common evolutionary ancestor.

Recombination between two homologous double-stranded DNA molecules, i.e. ones which share extensive nucleotide sequence similarity.

A technique in which genes with sequences similar to that of an unknown gene are sought, the objective being to gain an insight into the function of the unknown gene.

The situation that occurs when the same character state evolves independently in two lineages.

An artificial RNA comprising just one nucleotide.

The attachment of a sequence of identical nucleotides (e.g. AAAAA) to the end of a nucleic acid molecule, usually referring to the synthesis of single-stranded homopolymer extensions on the ends of a double-stranded DNA molecule.

A diploid nucleus that contains two identical alleles for a particular gene.

Transfer of a gene from one species to another.

A nucleotide sequence upstream of a gene that mediates the regulatory effect of a steroid hormone.

A protein that is continually expressed in all or at least most cells of a multicellular organism.

A family of proteins that bind to hydrophobic regions in other proteins in order to aid their folding.

The publicly funded project responsible for one of the draft human genome sequences and which continues to study the functions of human genes.

The attachment to one another, by base-pairing, of two complementary polynucleotides.

A technique that uses a labeled nucleic acid molecule as a probe to identify complementary or homologous molecules to which it base-pairs.

A weak electrostatic attraction between an electronegative atom such as oxygen or nitrogen and a hydrogen atom attached to a second electronegative atom.

Chemical interactions that result in hydrophobic groups becoming buried inside a protein.

An increase in the mutation rate of a genome.

A technique that uses antibody probing to locate the position of a protein in a tissue.

An electron microscopy technique that uses antibody labeling to identify the positions of specific proteins on the surface of a structure such as a ribosome.

The use of an antibody probe to detect a polypeptide synthesized by a cloned gene.

A protein involved in transport of molecules into the nucleus.

Techniques used to produce a specified mutation at a predetermined position in a DNA molecule.

Synthesis of infective λ phages from a preparation of λ proteins and a concatamer of λ DNA molecules.

Refers to a pair of alleles, neither of which displays dominance, the phenotype of a heterozygote being intermediate between the phenotypes of the two homozygotes.

A position in an alignment between two DNA sequences where an insertion or deletion has occurred.

A molecule that induces expression of a gene or operon by binding to a repressor protein and preventing the repressor from attaching to the operator.

A tree obtained by phylogenetic analysis.

The problem tackled by the early molecular biologists concerning the nature of the genetic code.

The part of a eukaryotic repressor that makes contact with the initiation complex

A mutant that is able to resist the toxic effects of an antibiotic or other type of inhibitor.

The codon, usually but not exclusively 5′–AUG–3′, found at the start of the coding region of a gene.

The complex of proteins that initiates transcription. Also the complex that initiates translation.

A protein that plays an ancillary role during initiation of translation.

The assembly upstream of a gene of the complex of proteins that will subsequently copy the gene into RNA.

A region of eukaryotic chromosomal DNA within which replication initiates at positions that are not clearly defined.

A component of the RNA polymerase II core promoter.

The tRNA, aminoacylated with methionine in eukaryotes or N-formylmethionine in bacteria, that recognizes the initiation codon during protein synthesis.

A modified version of adenosine, sometimes found at the wobble position of an anticodon.

A mutation that arises by insertion of one or more nucleotides into a DNA sequence.

A short transposable element found in bacteria.

A λ vector constructed by deleting a segment of non-essential DNA.

A less extensive form of pan-editing that occurs during processing of some viral RNAs.

A cloning strategy whereby insertion of a new piece of DNA into a vector inactivates a gene carried by the vector.

A sequence present in yeast mRNAs that affects degradation.

A segment of DNA that acts as the boundary point between two functional domains.

A Type I topoisomerase that catalyzes insertion of the λ genome into Escherichia coli DNA.

A set of genes and other DNA sequences that enable plasmids to capture genes from bacteriophages and other plasmids.

An internal segment of a polypeptide that is removed by a splicing process after translation.

The conversion of a gene coding for a protein that lacks an intein into one coding for an intein-plus protein, catalyzed by the spliced component of the intein.

A compound that can enter the space between adjacent base pairs of a double-stranded DNA molecule, often causing mutations.

The regions of a genome that do not contain genes.

A branch point within a phylogenetic tree, representing an organism or DNA sequence that is ancestral to those being studied.

A nucleotide sequence that enables the ribosome to assemble at an internal position in some eukaryotic mRNAs.

The period between cell divisions.

A chromosome, present in a cell during the period between cell divisions, which adopts a relatively uncondensed chromatin structure.

A sequence that recurs at many dispersed positions within a genome.

A clone fingerprinting technique that uses PCR to detect the relative positions of genome-wide repeats in cloned DNA fragments.

A position in bacterial DNA where termination of transcription occurs without the involvement of Rho.

A non-coding region within a discontinuous gene.

The conversion of a gene lacking an intron into one that contains an intron, catalyzed by a protein coded by that intron.

The hypothesis that introns evolved relatively early and are gradually being lost from eukaryotic genomes.

The hypothesis that introns evolved relatively late and are gradually accumulating in eukaryotic genomes.

Two identical nucleotide sequences repeated in opposite orientations in a DNA molecule.

A type of response module.

Two or more tRNAs that are charged with the same amino acid.

A segment of genomic DNA that has a uniform base composition which differs from that of the adjacent segments.

One of two or more atoms that have the same atomic number but different atomic weights.

A type of kinase that plays an intermediary role in some types of signal transduction involving STATs.

One interpretation of the intergenic DNA content of a genome.

The entire chromosome complement of a cell, with each chromosome described in terms of its appearance at metaphase.

A protein involved in transport of RNA out of or into the nucleus.

1000 base pairs.

The part of the centromere to which spindle microtubules attach.

A DNA polymerase enzyme, obtained by chemical modification of Escherichia coli DNA polymerase I, used primarily in chain termination DNA sequencing.

A mouse that has been engineered so that it carries an inactivated gene.

The DNA polymerase I enzyme of Escherichia coli.

The nucleotide sequence surrounding the initiation codon of a eukaryotic mRNA.

The cluster of three genes that code for enzymes involved in utilization of lactose by Escherichia coli.

The regulatory protein that controls transcription of the lactose operon in response to the presence or absence of lactose in the environment.

The strand of the double helix which is copied in a discontinuous fashion during genome replication.

Refers to the lariat-shaped intron RNA that results from splicing a GU–AG intron.

Transfer of a gene from one species to another.

The untranslated region of an mRNA upstream of the initiation codon.

The strand of the double helix which is copied in a continuous fashion during genome replication.

A mutation that results in partial loss of a characteristic.

A mutation that results in death of the cell or organism.

A dimerization domain commonly found in DNA-binding proteins.

An enzyme that synthesizes phosphodiester bonds as part of DNA replication, repair and recombination processes.

A type of genome-wide repeat, often with transposable activity.

One type of human LINE.

The physical association between two genes that are on the same chromosome.

The procedure used to assign map positions to genes by genetic crosses.

The DNA that links nucleosomes: the ‘string’ in the ‘beads-on-a-string’ model for chromatin structure.

A histone, such as H1, that is located outside of the nucleosome core octamer.

The chromosomal location of a genetic or DNA marker.

A DNA sequence that maintains a functional domain in an open active configuration.

A statistical measure of linkage as revealed by pedigree analysis.

A nucleotide excision repair process of Escherichia coli that results in excision and resynthesis of up to 2 kb of DNA.

A mutation that reduces or abolishes a protein’s activity.

A type of genome-wide repeat typified by the presence of long terminal repeats (LTRs).

The type of bacteriophage infection that involves integration of the phage genome into the host DNA molecule.

A protein used to destabilize the bacterial cell wall prior to DNA purification.

The type of bacteriophage infection that involves lysis of the host cell immediately after the initial infection, with no integration of the phage DNA molecule into the host genome.

The stage of the cell cycle when mitosis or meiosis occurs.

One of the larger gene-deficient chromosomes seen in the nuclei of chickens and various other species.

A DNA-binding domain found in several transcription factors involved in plant development.

Addition of methyl groups to positions on newly synthesized DNA strands that correspond with the positions of methylation on the parent strand.

The larger of the two grooves that spiral around the surface of the B-form of DNA.

A mammalian multigene family coding for cell surface proteins and including several multiallelic genes.

A chart showing the positions of genetic and/or physical markers in a genome.

A signal transduction pathway.

A collection of DNA fragments spanning a chromosome or the entire genome and used in STS mapping.

A distinctive feature on a genome map. Also a gene, carried by a cloning vector, that codes for a distinctive protein product and/or phenotype and so can be used to determine if a cell contains a copy of the cloning vector.

An analytical technique in which ions are separated according to their charge-to-mass ratios.

A Drosophila gene that is expressed in the parent and whose mRNA is subsequently injected into the egg, after which it influences development of the embryo.

The equivalent of male and female for a eukaryotic microorganism.

The ability of yeast cells to change from a to α mating type, or vice versa, by gene conversion.

A type of mass spectrometry used in proteomics.

An AT-rich segment of a eukaryotic genome that acts as an attachment point to the nuclear matrix.

A protein, coded by a gene in an intron, thought to be involved in splicing.

A method for construction of phylogenetic trees.

A protein complex that forms a contact between various activators and the C-terminal domain of the largest subunit of RNA polymerase II.

1000 kb; 1  000 000 bp.

The series of events, involving two nuclear divisions, by which diploid nuclei are converted to haploid gametes.

Denaturation of a double-stranded DNA molecule.

The temperature at which the two strands of a double-stranded nucleic acid molecule or base-paired hybrid detach as a result of complete breakage of hydrogen bonding.

The experiment which showed that cellular DNA replication occurs by the semiconservative process.

The transcript of a protein-coding gene.

A chromosome at the metaphase stage of cell division, when the chromatin takes on its most condensed structure and features such as the banding pattern can be visualized.

A protein that binds to methylated CpG islands and may influence acetylation of nearby histones.

An enzyme involved in the direct repair of alkylation mutations.

A low-density array of DNA molecules used for parallel hybridization analysis.

A type of simple sequence length polymorphism comprising tandem copies of, usually, di-, tri- or tetranucleotide repeat units. Also called a simple tandem repeat (STR).

One of the smaller, gene-rich chromosomes seen in the nuclei of chickens and various other species.

The name given to the pair of exons carried by a cloning vector used in the exon-trapping procedure.

A medium that provides only the minimum nutritional requirements for growth of a microorganism.

A type of simple sequence length polymorphism comprising tandem copies of repeats that are a few tens of nucleotides in length. Also called a variable number of tandem repeats (VNTR).

The smaller of the two grooves that spiral around the surface of the B-form of DNA.

A position in a double-stranded DNA molecule where base-pairing does not occur because the nucleotides are not complementary; in particular, a non-base-paired position resulting from an error in replication.

A DNA repair process that corrects mismatched nucleotide pairs by replacing the incorrect nucleotide in the daughter polynucleotide.

An alteration in a nucleotide sequence that converts a codon for one amino acid into a codon for a second amino acid.

The genome present in the mitochondria of a eukaryotic cell.

One of the energy-generating organelles of eukaryotic cells.

The series of events that results in nuclear division.

An organism which is relatively easy to study and hence can be used to obtain information that is relevant to the biology of a second organism that is more difficult to study.

A range of techniques used for locating bound proteins on DNA molecules.

A technique used to identify nucleotides involved in interactions with a DNA-binding protein.

A technique used to identify nucleotides involved in interactions with a DNA-binding protein.

A person who studies the molecular life sciences.

A protein that helps other proteins to fold.

A device based on the inferred mutation rate that enables times to be assigned to the branch points in a gene tree.

A technique for preparing restricted DNA molecules for optical mapping.

The gradual changes that occur in genomes over time as a result of the accumulation of mutations and structural rearrangements resulting from recombination and transposition.

The area of research comprising molecular biology, biochemistry and cell biology, as well as some aspects of genetics and physiology.

A set of techniques that enable the evolutionary relationships between DNA sequences to be inferred by making comparisons between those sequences.

A sexual cross in which the inheritance of one pair of alleles is followed.

Refers to two or more organisms or DNA sequences that are derived from a single ancestral organism or DNA sequence.

A RNA degradation process in eukaryotes.

A gene, cloning vector or other genetic element that is present in multiple copies in a single cell.

A type of zinc-finger DNA-binding domain.

A group of genes, clustered or dispersed, with related nucleotide sequences.

An alignment of three or more nucleotide sequences.

The different alternative forms of a gene that has more than two alleles.

The situation that occurs when a single nucleotide in a DNA sequence undergoes two mutational changes, giving rise to two new alleles, both of which differ from each other and from the parent at that nucleotide position.

A genetic cross in which the inheritance of three or more markers is followed.

A hypothesis that holds that modern humans in the Old World are descended from Homo erectus populations that left Africa over 1 million years ago.

A chemical or physical agent that can cause a mutation in a DNA molecule.

Treatment of a group of cells or organisms with a mutagen as a means of inducing mutations.

A cell or organism that possesses a mutation.

A protein complex that is constructed during the SOS response of Escherichia coli.

An alteration in the nucleotide sequence of a DNA molecule.

A set of techniques for detection of mutations in DNA molecules.

A set of techniques for determining if a DNA molecule contains a specific mutation.

The end of a polypeptide that has a free amino group.

The preservation of favorable alleles and the rejection of injurious ones.

An N-terminal amino acid sequence that influences the degradation of a protein in which it is found.

A method for construction of phylogenetic trees.

A position in a double-stranded DNA molecule where one of the polynucleotides is broken as a result of the absence of a phosphodiester bond.

One of the purines or pyrimidines that form part of the molecular structure of a nucleotide.

The attachment of sugar units to an asparagine in a polypeptide.

An RNA molecule that does not code for a protein.

Another name for the double-strand break repair process.

The situation whereby the effect of a mutation is never observed during the lifetime of a mutant organism.

A hydrophobic (water-hating) chemical group.

A process for degradation of eukaryotic mRNAs that is initiated by the presence of an internal termination codon.

An alteration in a nucleotide sequence that changes a triplet coding for an amino acid into a termination codon.

A mutation that converts a codon for one amino acid into a codon for a second amino acid.

The transfer of RNA from an electrophoresis gel to a membrane prior to northern hybridization.

A technique used for detection of a specific RNA molecule against a background of many other RNA molecules.

The DNA molecules present in the nucleus of a eukaryotic cell.

A technique for determining the three-dimensional structure of large molecules.

A proteinaceous scaffold-like network that permeates the cell.

The complex of proteins present at a nuclear pore.

A family of receptor proteins that bind hormones as an intermediate step in modulation of genome activity by these hormones.

An enzyme that degrades a nucleic acid molecule.

A technique that uses nuclease digestion to determine the positions of proteins on DNA or RNA molecules.

The term first used to describe the acidic chemical compound isolated from the nuclei of eukaryotic cells. Now used specifically to describe a polymeric molecule comprising nucleotide monomers, such as DNA and RNA.

Formation of a double-stranded hybrid by base-pairing between complementary polynucleotides.

The DNA-containing region of a prokaryotic cell.

The region of the eukaryotic nucleus in which rRNA transcription occurs.

A purine or pyrimidine base attached to a five-carbon sugar.

The complex of histones and DNA that is the basic structural unit in chromatin.

A change in the conformation of a nucleosome, associated with a change in access to the DNA to which the nucleosome is attached.

A purine or pyrimidine base attached to a five-carbon sugar, to which a mono-, di-, or triphosphate is also attached. The monomeric unit of DNA and RNA.

A repair process that corrects various types of DNA damage by excising and resynthesizing a region of a polynucleotide.

The membrane-bound structure of a eukaryotic cell in which the chromosomes are contained.

A basal promoter element.

One of the short segments of RNA-primed DNA synthesized during replication of the lagging strand of the double helix.

A short synthetic single-stranded DNA molecule.

An in vitro mutagenesis technique in which a synthetic oligonucleotide is used to introduce a predetermined nucleotide alteration into the gene to be mutated.

The use of an oligonucleotide as a hybridization probe.

The attachment of sugar units to a serine or threonine in a polypeptide.

A structure formed during assembly of the transcription initiation complex consisting of the RNA polymerase and/or accessory proteins attached to the promoter, after the DNA has been opened up by breakage of base pairs.

A series of codons starting with an initiation codon and ending with a termination codon. The part of a protein-coding gene that is translated into protein.

One of the organisms being compared in a phylogenetic analysis.

The nucleotide sequence to which a repressor protein binds to prevent transcription of a gene or operon.

A set of adjacent genes in a bacterial genome, transcribed from a single promoter and subject to the same regulatory regime.

A technique for the direct visual examination of restricted DNA molecules.

Examination of a DNA sequence for open reading frames in order to locate the genes.

A site on a DNA molecule where replication initiates.

A set of proteins that binds to the origin recognition sequence.

A component of a eukaryotic origin of replication.

A group of homologous genes whose functions are unknown.

An electrophoresis system in which the field alternates between pairs of electrodes set at an angle of 45°, used to separate large DNA molecules.

Refers to homologous genes located in the genomes of different organisms.

An organism or DNA sequence that is used to root a phylogenetic tree.

A hypothesis which holds that modern humans evolved in Africa, moving to the rest of the Old World between 100 000 and 50 000 years ago, displacing the descendants of Homo erectus that they encountered.

Two genes whose coding regions overlap.

A high-capacity vector that combines features of bacteriophage P1 vectors and bacterial artificial chromosomes.

Developmental genes that establish the basic segmentation pattern of the Drosophila embryo.

The extensive insertion of nucleotides into an abbreviated RNA, resulting in a functional molecule.

Refers to two or more homologous genes located in the same genome.

Refers to a helix whose strands can be separated without unwinding.

The genotype possessed by one or both of the parents in a genetic cross.

An approach that decides between different phylogenetic tree topologies by identifying the one that involves the shortest evolutionary pathway.

The type of linkage usually displayed by a pair of genetic and/or physical markers on the same chromosome, the markers not always being inherited together because of the possibility of recombination between them.

Digestion of DNA with a restriction endonuclease under limiting conditions so that not all restriction sites are cut.

A chart showing the genetic relationships between the members of a human family.

The use of pedigree charts to analyze the inheritance of a genetic or DNA marker in a human family.

A DNA transposon of Drosophila.

A sugar comprising five carbon atoms.

The chemical link between adjacent amino acids in a polypeptide.

A polynucleotide analog in which the sugar–phosphate backbone is replaced by amide bonds.

The site in the ribosome occupied by the tRNA attached to the growing polypeptide during translation.

The enzyme activity that synthesizes peptide bonds during translation.

Conditions under which a conditional-lethal mutant is able to survive.

Amino acid sequences that influence the degradation of proteins in which they are found.

A virus that infects a bacterium.

A technique for identifying proteins that interact with one another.

A collection of clones carrying different DNA fragments, used in phage display.

A cloning vector comprising a mixture of plasmid and phage DNA.

A classificatory approach based on the numerical typing of as many characters as possible.

The observable characteristics displayed by a cell or organism.

A type of enzyme that can break phosphodiester bonds.

The chemical link between adjacent nucleotides in a polynucleotide.

An electronic method for determining the positions of radioactive markers in a microarray or on a hybridization membrane.

A component of the FRAP technique for studying protein mobility in the nucleus.

A technique that uses pulses of light to construct an oligonucleotide from light-activated nucleotide substrates.

An Escherichia coli enzyme involved in photoreactivation repair.

A modified nucleotide resulting from treatment of DNA with ultraviolet radiation.

A DNA repair process in which cyclobutyl dimers and (6–4) photoproducts are corrected by a light-activated enzyme.

A classification scheme that indicates the evolutionary relationships between organisms.

The use of molecular biology techniques to construct a genome map.

A structure involved in bringing a pair of bacteria together during conjugation; possibly the tube through which DNA is transferred.

A zone of clearing on a lawn of bacteria caused by lysis of the cells by infecting bacteriophages.

A usually circular piece of DNA often found in bacteria and some other types of cell.

Refers to a helix whose strands can only be separated by unwinding.

A character state possessed by a remote common ancestor of a group of organisms.

A mutation that results from a single nucleotide change in a DNA molecule.

A hydrophilic (water-loving) chemical group.

Electrophoresis carried out in a polyacrylamide gel and used to separate DNA molecules between 10 and 1500 bp in length.

A protein that aids poly(A) polymerase during polyadenylation of eukaryotic mRNAs, and which plays a role in maintenance of the tail after synthesis.

The addition of a series of As to the 3′ end of a eukaryotic mRNA.

A form of editing that occurs with many animal mitochondrial RNAs, resulting in a termination codon being formed by adding a poly(A) tail to an mRNA that ends with the nucleotides U or UA.

The enzyme that attaches a poly(A) tail to the 3′ end of a eukaryotic mRNA.

A series of A nucleotides attached to the 3′ end of a eukaryotic mRNA.

A compound made up of a long chain of identical or similar units.

A technique that results in exponential amplification of a selected region of a DNA molecule.

Refers to a locus that is represented by a number of different alleles or haplotypes in the population as a whole.

A single-stranded DNA or RNA molecule.

An enzyme that adds phosphate groups to the 5′ ends of DNA molecules.

A polymer of amino acids.

A group of DNA sequences that are derived from two or more distinct ancestral sequences.

A translation product consisting of a series of linked proteins which are processed by proteolytic cleavage to release the mature proteins.

A pyrimidine-rich region near the 3′ end of a GU–AG intron.

An mRNA molecule that is being translated by more than one ribosome at the same time.

A procedure that uses information on the map position of a gene to obtain a clone of that gene.

Refers to the different levels of expression that result after insertion of a gene at different positions in a eukaryotic genome.

A complex of proteins, derived from a pre-RC, that forms at a eukaryotic origin of replication during the replication process and ensures that the origin is used just once per cell cycle.

A DNA-binding motif found in a variety of proteins.

The structure comprising the small subunit of the ribosome, the initiator tRNA plus ancillary factors that forms the initial association with the mRNA during protein synthesis. Also the structure that forms at the core promoter of a gene transcribed by RNA polymerase II.

The primary transcript of a protein-coding gene.

A complex of proteins formed during initiation of replication in bacteria.

A protein complex that is constructed at a eukaryotic origin of replication and enables initiation of replication to occur.

The initial product of transcription of a gene or group of genes, subsequently processed to give the mature transcript(s).

The primary transcript of a gene or group of genes specifying rRNA molecules.

An intermediate in the splicing pathway for a GU–AG intron.

The primary transcript of a gene or group of genes specifying tRNA molecules.

A component of the bacterial promoter.

The sequence of amino acids in a polypeptide.

The initial product of transcription of a gene or group of genes, subsequently processed to give the mature transcript(s).

The RNA polymerase enzyme that synthesizes RNA primers during bacterial DNA replication.

A short oligonucleotide that is attached to a single-stranded DNA molecule in order to provide a start point for strand synthesis.

A protein complex involved in genome replication.

A procedure that attempts to identify patterns in a large dataset of variable character states.

An unusual infectious agent that consists purely of protein.

A pseudogene that results from integration into the genome of a reverse-transcribed copy of an mRNA.

Refers to the amount of DNA synthesis that is carried out by a DNA polymerase before dissociation from the template.

The controlled movement of a ribosome from one reading frame to another at an internal position within a gene.

The possibility that under some circumstances an organism can increase the rate at which mutations occur in a specific gene.

An organism whose cells lack a distinct nucleus.

An accessory protein involved in genome replication in eukaryotes.

A type of activation domain.

DNA that has been transferred from one organelle genome to another.

The nucleotide sequence, upstream of a gene, to which RNA polymerase binds in order to initiate transcription.

The completion of successful initiation of transcription that occurs when the RNA polymerase moves away from the promoter sequence.

The stage in transcription during which the polymerase moves away from the promoter region and becomes committed to making a transcript.

The 3′→5′ exonuclease activity possessed by some DNA polymerases which enables the enzyme to replace a misincorporated nucleotide.

The integrated form of the genome of a lysogenic bacteriophage.

An enzyme that degrades protein.

A multi-subunit protein structure that is involved in the degradation of other proteins.

The polymeric compound made of amino acid monomers.

Separation of proteins in an electrophoresis gel.

Various techniques for making directed alterations in protein molecules, often to improve the properties of enzymes used in industrial processes.

The adoption of a folded structure by a polypeptide.

A map showing the interactions between all or some of the proteins in a proteome.

A technique that links together adjacent proteins in order to identify proteins that are positioned close to one another in a structure such as a ribosome.

The collection of functioning proteins synthesized by a living cell.

A variety of techniques used to study proteomes.

An RNA genome that existed during the RNA world.

A cell from which the cell wall has been completely removed.

An organism that has no nutritional requirements beyond those of the wild type and which can grow on minimal medium.

An inactivated and hence non-functional copy of a gene.

A codon that specifies either the start or the end of a gene.

A tabular analysis for predicting the genotypes of the progeny resulting from a genetic cross.

One of the two types of nitrogenous base found in nucleotides.

One of the two types of nitrogenous base found in nucleotides.

A novel DNA sequencing method in which addition of a nucleotide to the end of a growing polynucleotide is detected directly by conversion of the released pyrophosphate into a flash of chemiluminescence.

A PCR method that enables the number of DNA molecules in a sample to be estimated.

The structure resulting from the association of two or more polypeptides.

A PCR-based technique for mapping the end of an RNA molecule.

A collection of rodent cell lines that contain different fragments of a second genome, constructed by a technique involving irradiation and used as a mapping reagent, for example in studies of the human genome.

A radioactive atom incorporated into a molecule and whose radioactive emissions are subsequently used to detect and follow that molecule during a biochemical reaction.

The technique for attaching a radioactive atom to a molecule.

The process that leads to alleles gradually changing their frequency in a population.

A protein involved in signal transduction.

A series of triplet codons in a DNA sequence.

A mutation that changes a termination codon into a codon specifying an amino acid, and hence results in readthrough of the termination codon.

An Escherichia coli protein involved in homologous recombination.

An enzyme complex involved in homologous recombination in Escherichia coli.

The allele that is not expressed in a heterozygote.

The exchange of DNA between two double-stranded molecules, occurring as a result of recombination, such that the end of one molecule is exchanged for the end of the other molecule.

An α-helix in a DNA-binding protein, one that is responsible for recognition of the target nucleotide sequence.

A progeny member that possesses neither of the combinations of alleles displayed by the parents.

A DNA molecule created in the test tube by ligating pieces of DNA that are not normally joined together.

The techniques involved in the construction, study and use of recombinant DNA molecules.

A protein synthesized in a recombinant cell as the result of expression of a cloned gene.

A diverse family of enzymes that catalyze site-specific recombination events.

A large-scale rearrangement of a DNA molecule.

The proportion of recombinant progeny arising from a genetic cross.

A region of a chromosome where crossovers occur at a higher frequency than the average for the chromosome as a whole.

A DNA repair process that mends double-stranded breaks.

Control over bacterial gene expression that depends on the influence of regulatory proteins.

A mutant that has a defect in a promoter or other regulatory sequence.

A protein that plays an ancillary role during termination of translation.

The return of a denatured molecule to its natural state.

A DNA sequence that is repeated two or more times in a DNA molecule or genome.

A clone fingerprinting technique that involves determining the positions of genome-wide repeats in cloned DNA fragments.

A clone fingerprinting technique that uses PCR to detect the relative positions of genome-wide repeats in cloned DNA fragments.

A λ vector designed so that insertion of new DNA is by replacement of part of the non-essential region of the λ DNA molecule.

A technique for transfer of colonies from one Petri dish to another, such that their relative positions on the surface of the agar medium are retained.

A multi-subunit accessory protein involved in eukaryotic genome replication.

A large structure attached to the nuclear matrix; the site of genome replication.

The region of a double-stranded DNA molecule that is being opened up to enable DNA replication to occur.

A set of proteins that regulate genome replication, in particular by ensuring that only one round of genome replication occurs per cell cycle.

A protein responsible for detachment of single-strand binding proteins during genome replication.

A site on a DNA molecule where replication initiates.

The main single-strand binding protein involved in replication of eukaryotic DNA.

An error in replication that leads to an increase or decrease in the number of repeat units in a tandem repeat such as a microsatellite.

The double-stranded form of the M13 DNA molecule found within infected Escherichia coli cells.

Transposition that results in copying of the transposable element.

A complex of proteins involved in genome replication.

A gene whose phenotype can be assayed and which can therefore be used to determine the function of a regulatory DNA sequence.

Separation of a pair of recombining double-stranded DNA molecules.

A sequence motif found upstream of various genes that enables transcription initiation by RNA polymerase II to respond to general signals from outside of the cell.

An enzyme that cuts DNA molecules at a limited number of specific nucleotide sequences.

A restriction fragment whose length is variable because of the presence of a polymorphic restriction site at one or both ends.

Determination of the positions of restriction sites in a DNA molecule by analyzing the sizes of restriction fragments.

Conditions under which a conditional-lethal mutant is unable to survive.

A genetic element that transposes via an RNA intermediate.

A retroelement that does not have LTRs.

Transposition via an RNA intermediate.

A genome-wide repeat with a sequence similar to an integrated retroviral genome and possibly with retrotransposition activity.

A truncated retroviral genome integrated into a host chromosome.

A virus with an RNA genome that integrates into the genome of its host cell.

A polymerase that synthesizes DNA on an RNA template.

PCR in which the first step is carried out by reverse transcriptase, so RNA can be used as the starting material.

A protein involved in termination of transcription of some bacterial genes.

A position in bacterial DNA where termination of transcription occurs with the involvement of Rho.

A type of DNA-binding domain.

An enzyme that degrades RNA.

An enzyme involved in processing pre-tRNA in bacteria.

An enzyme involved in processing eukaryotic pre-rRNA.

An enzyme involved in processing pre-tRNA in bacteria.

A common type of RNA-binding domain.

The sugar component of a ribonucleotide.

One of the protein components of a ribosome.

The RNA molecules that are components of ribosomes.

One of the protein–RNA assemblies on which translation occurs.

The nucleotide sequence that acts as the attachment site for the small subunit of the ribosome during initiation of translation in bacteria.

A protein responsible for disassembly of the ribosome at the end of protein synthesis in bacteria.

An RNA molecule that has catalytic activity.

Ribonucleic acid, one of the two forms of nucleic acid in living cells; the genetic material for some viruses.

An enzyme that makes a DNA copy of an RNA template; a reverse transcriptase.

An enzyme that makes an RNA copy of an RNA template.

A process by which nucleotides not coded by a gene are introduced at specific positions in an RNA molecule after transcription.

An RNA degradation process in eukaryotes.

An enzyme that synthesizes RNA on a DNA or RNA template.

The eukaryotic RNA polymerase that transcribes ribosomal RNA genes.

The eukaryotic RNA polymerase that transcribes protein-coding and snRNA genes.

The eukaryotic RNA polymerase that transcribes tRNA and other short genes.

An RNA copy of a gene.

The early period of evolution when all biological reactions were centered on RNA.

A replication process that involves continual synthesis of a polynucleotide which is ‘rolled off’ of a circular template molecule.

Refers to a phylogenetic tree that provides information on the past evolutionary events that have led to the organisms or DNA sequences being studied.

The stage of the cell cycle when DNA synthesis occurs.

The unit of measurement for a sedimentation coefficient.

An enzyme that degrades single-stranded DNA or RNA molecules, including single-stranded regions in predominantly double-stranded molecules.

A stress-activated signal transduction pathway.

Repetitive DNA that forms a satellite band in a density gradient.

A series of sequence contigs separated by sequence gaps.

An AT-rich segment of a eukaryotic genome that acts as an attachment point to the nuclear matrix.

A system used during initiation of eukaryotic translation, in which the pre-initiation complex attaches to the 5′-terminal cap structure of the mRNA and then scans along the molecule until it reaches an initiation codon.

An intermediate in a certain type of signal transduction pathway.

The conformations, such as α-helix and β-sheet, taken up by a polypeptide.

The centrifugal technique used to measure the sedimentation coefficient of a molecule or structure.

The value used to express the velocity at which a molecule or structure sediments when centrifuged in a dense solution.

Developmental genes that provide greater definition to the segmentation pattern of the Drosophila embryo established by the action of the pair-rule genes.

The separation of homologous chromosomes, or members of allele pairs, into different gametes during meiosis.

A gene carried by a vector and conferring a recognizable characteristic on a cell containing the vector or a recombinant DNA molecule derived from the vector.

A medium that supports the growth of only those cells that carry a particular genetic marker.

DNA that appears to have no function and apparently contributes nothing to the cell in which it is found.

The mode of DNA replication in which each daughter double helix is made up of one polynucleotide from the parent and one newly synthesized polynucleotide.

An enzyme used in chain termination DNA sequencing.

A contiguous DNA sequence obtained as an intermediate in a genome sequencing project.

A method for rapid sequence acquisition in which a few random sequences are obtained from a cloned fragment, the rationale being that if the fragment contains any genes then there is a good chance that at least some of them will be revealed by these random sequences.

A DNA sequence that is unique in the genome.

A method for studying the composition of a transcriptome.

A reproductive cell; a cell that divides by meiosis.

A chromosome that is involved in sex determination.

The ribosome binding site upstream of an Escherichia coli gene.

An intermediate in the RNA interference pathway.

A nucleotide excision repair process of Escherichia coli that results in excision and resynthesis of about 12 nucleotides of DNA.

A type of simple sequence length polymorphism comprising tandem copies of, usually, di-, tri- or tetranucleotide repeat units. Also called a microsatellite.

A genome sequencing strategy in which the molecules to be sequenced are randomly broken into fragments which are then sequenced individually.

A vector that can replicate in the cells of more than one organism (e.g. in Escherichia coli and in yeast).

A short sequence at the N terminus of some proteins that directs the protein across a membrane.

Control of cellular activity, including genome expression, via a cell-surface receptor that responds to an external signal.

A regulatory sequence that reduces the rate of transcription of a gene or genes located some distance away in either direction.

A change in a DNA sequence that has no effect on the expression or functioning of any gene or gene product.

A rigorous mathematical approach to alignment of nucleotide sequences.

An array of repeat sequences that display length variations.

A type of genome-wide repeat, typified by the Alu sequences found in the human genome.

A DNA sequence that is not repeated elsewhere in the genome.

A point mutation that is carried by some individuals of a population.

A single gene, with no homolog, whose function is unknown.

One of the proteins that attach to single-stranded DNA in the region of the replication fork, preventing base pairs forming between the two parent strands before they have been copied.

A DNA or RNA molecule that comprises just a single polynucleotide.

A technique for locating the position of a protein in a protein–RNA complex, such as a ribosome, by making use of the ability of Fe(II) ions to generate hydroxyl radicals which cleave nearby RNA phosphodiester bonds.

Techniques used to produce a specified mutation at a predetermined position in a DNA molecule.

Recombination between two double-stranded DNA molecules that have only short regions of nucleotide sequence similarity.

The translocation of a ribosome along a short non-coding nucleotide sequence between the termination codon of one gene and the initiation codon of a second gene.

A group of proteins involved in signal transduction.

A type of short eukaryotic RNA molecule with various roles in the cell.

Structures involved in splicing GU–AG and AU–AC introns and in other RNA processing events, comprising one or two snRNA molecules complexed with proteins.

A type of short eukaryotic RNA molecule involved in splicing GU–AG and AU–AC introns and in other RNA processing events.

A type of short eukaryotic RNA molecule involved in chemical modification of rRNA.

A non-reproductive cell; a cell that divides by mitosis.

A procedure that uses ultrasound to cause random breaks in DNA molecules.

A series of biochemical changes that occur in Escherichia coli in response to damage to the genome and other stimuli.

A technique used for detection of a specific restriction fragment against a background of many other restriction fragments.

A phylogenetic tree that shows the evolutionary relationships between a group of species.

The protein–RNA complex involved in splicing GU–AG or AU–AC introns.

The removal of introns from the primary transcript of a discontinuous gene.

The series of events that converts a discontinuous pre-mRNA into a functional mRNA.

A mutation that arises from an error in replication.

Proteins thought to play regulatory roles during splicing of GU–AG introns.

A protein that plays a role in splice-site selection during splicing of GU–AG introns.

A type of protein that responds to binding of an extracellular signaling compound to a cell surface receptor by activating a transcription factor.

A progenitor cell that divides continually throughout the lifetime of an organism.

A structure made up of a base-paired stem and non-base-paired loop, which can form in a single-stranded polynucleotide that contains an inverted repeat.

A type of extracellular signaling compound.

A protein that binds a steroid hormone after the latter has entered the cell, as an intermediate step in modulation of genome activity.

An end of a double-stranded DNA molecule where there is a single-stranded extension.

A promoter that directs a relatively large number of productive initiations per unit time.

A segment of a polypeptide that folds independently of other segments. Also, a loop of eukaryotic DNA, predominantly in the form of the 30 nm chromatin fiber, attached to the nuclear matrix.

A physical mapping procedure that locates the positions of sequence tagged sites (STSs) in a genome.

A DNA fragment contained within a λ vector that is replaced by the DNA to be cloned.

Commonly used as a synonym for a point mutation.

A conformational state in which a double helix is overwound or underwound so that superhelical coiling occurs.

The extreme form of wobble that occurs in vertebrate mitochondria.

A mutation in one gene that reverses the effect of a mutation in a second gene.

A cell-like structure comprising a mass of cytoplasm and many nuclei.

A mutation that changes a codon into a second codon that specifies the same amino acid.

Refers to a pair of genomes in which at least some of the genes are located at similar map positions.

Part of the structure of a tRNA molecule.

An enzyme that adds phosphate groups to the 5′ ends of DNA molecules.

A type of protein involved in initiation of transcription by RNA polymerase II.

DNA sequence motifs that are repeated head to tail.

Direct repeats that are adjacent to each other.

A component of the general transcription factor TFIID, the part that recognizes the TATA box of the RNA polymerase II promoter.

A component of the RNA polymerase II core promoter.

The spontaneous change of a molecule from one structural isomer to another.

Structural isomers that are in dynamic equilibrium.

One of several components of the general transcription factor TFIID, playing ancillary roles in recognition of the TATA box.

A type of DNA-binding domain.

The portion of the Ti plasmid that is transferred to the plant DNA.

The enzyme that maintains the ends of eukaryotic chromosomes by synthesizing telomeric repeat sequences.

The end of a eukaryotic chromosome.

A protein that binds to and regulates the length of a telomere.

A type of conditional-lethal mutation, one that is expressed only above a threshold temperature.

The polynucleotide that is copied during a strand synthesis reaction catalyzed by a DNA or RNA polymerase.

An enzyme that synthesizes DNA in accordance with the sequence of a template.

Synthesis of a DNA molecule on a DNA or RNA template.

An enzyme that synthesizes RNA in accordance with the sequence of a template.

Synthesis of an RNA molecule on a DNA or RNA template.

An enzyme that synthesizes DNA without the use of a template.

An enzyme that synthesizes RNA without the use of a template.

The polynucleotide that acts as the template for RNA synthesis during transcription of a gene.

An enzyme that adds one or more nucleotides to the 3′ end of a DNA molecule.

One of the three codons that mark the position where translation of an mRNA should stop.

A protein that plays an ancillary role in termination of transcription.

One of several sequences on a bacterial genome involved in termination of genome replication.

The structure resulting from folding the secondary structural units of a polypeptide.

A genetic cross between a double heterozygote and a double homozygote.

A DNA sequencing method that uses PCR to generate chain-terminated polynucleotides.

Able to withstand high temperatures.

One of the pyrimidine bases found in DNA.

The large plasmid found in those Agrobacterium tumefaciens cells able to direct crown gall formation on certain species of plants.

Melting temperature.

A type of DNA transposon that does not have flanking insertion sequences.

The branching pattern of a phylogenetic tree.

Refers to a cell that is not committed to a single developmental pathway and can hence give rise to all types of differentiated cell.

The untranslated region of an mRNA downstream of the termination codon.

An RNA copy of a gene.

The synthesis of an RNA copy of a gene.

The non-base-paired region of the double helix, maintained by RNA polymerase, within which transcription occurs.

A nucleotide excision repair process that results in repair of the template strands of genes.

A large structure attached to the nuclear matrix; the site of RNA synthesis.

The assembly, upstream of a gene, of the complex of proteins that will subsequently copy the gene into RNA.

The entire mRNA content of a cell.

Regulatory mechanisms that control protein synthesis by acting on a single transcript or a small group of transcripts coding for related proteins.

Transfer of a nucleosome from one DNA molecule to another.

Transfer of bacterial genes from one cell to another by packaging in a phage particle.

The use of transduction to map the relative positions of genes in a bacterial genome.

The introduction of purified phage DNA molecules into a bacterial cell.

A bacterial RNA involved in protein degradation.

A small RNA molecule that acts as an adaptor during translation and is responsible for decoding the genetic code.

A cell that has become transformed by the uptake of naked DNA.

The acquisition by a cell of new genes by the uptake of naked DNA.

The use of transformation to map the relative positions of genes in a bacterial genome.

The compound, now known to be DNA, responsible for transformation of an avirulent Streptococcus pneumoniae bacterium into a virulent form.

A mouse that carries a cloned gene.

A point mutation that replaces a purine with another purine, or a pyrimidine with another pyrimidine.

The synthesis of a polypeptide, the amino acid sequence of which is determined by the nucleotide sequence of an mRNA in accordance with the rules of the genetic code.

A form of slippage in which a large part of an mRNA is skipped during translation, elongation of the original protein continuing after the bypassing event.

The movement of a ribosome along an mRNA molecule during translation.

A genetic element that can move from one position to another in a DNA molecule.

A bacteriophage that transposes as part of its infection cycle.

An enzyme that catalyzes transposition of a transposable genetic element.

The movement of a genetic element from one site to another in a DNA molecule.

A genetic element that can move from one position to another in a DNA molecule.

A gene isolation technique that involves inactivation of a gene by movement of a transposon into its coding sequence, followed by the use of a transposon-specific hybridization probe to isolate a copy of the tagged gene from a clone library.

A point mutation that involves a purine being replaced by a pyrimidine, or vice versa.

A disease that results from the expansion of an array of trinucleotide repeats in or near to a gene.

A technique for determining the coding specificity of a triplet of nucleotides.

A DNA structure comprising three polynucleotides.

The presence of three copies of a homologous chromosome in a nucleus that is otherwise diploid.

The enzyme responsible for the post-transcriptional attachment of the triplet 5′–CCA–3′ to the 3′ end of a tRNA molecule.

A protein involved in attenuation regulation of some operons in bacteria such as Bacillus subtilis.

A phylogenetic tree that depicts the actual series of evolutionary events that led to the group of organisms or DNA sequences being studied.

A gene relic that lacks a segment from one end of the original, complete gene.

The protein that binds to a bacterial terminator sequence and mediates termination of genome replication.

A composite structure made up of two or more Group II and/or Group III introns embedded in each other.

A method for separation of proteins used especially in studies of the proteome.

The basic cap structure, consisting of 7-methylguanosine attached to the 5′ end of an mRNA.

A cap structure comprising the basic 5′-terminal cap plus an additional methylation of the ribose of the second nucleotide.

A cap structure comprising the basic 5′-terminal cap plus methylation of the riboses of the second and third nucleotides.

A 76-amino-acid protein which, when attached to a second protein, acts as a tag directing that protein for degradation.

A recombination event that results in duplication of a segment of DNA.

A recombination event that results in duplication of a segment of DNA.

Mendel’s term for a gene.

Refers to a phylogenetic tree that merely illustrates relationships between the organisms or DNA sequences being studied, without providing information about the past evolutionary events that have occurred.

Towards the 5′ end of a polynucleotide.

A component of an RNA polymerase I promoter.

Components of a eukaryotic promoter that lie upstream of the position where the initiation complex is assembled.

One of the pyrimidine bases found in RNA.

A uracil-rich nuclear RNA molecule including the snRNAs and snoRNAs.

A multienzyme complex involved in the short patch repair process of Escherichia coli.

Part of the structure of a tRNA molecule.

A particular type of attractive or repulsive non-covalent bond.

A type of simple sequence length polymorphism comprising tandem copies of repeats that are a few tens of nucleotides in length. Also called a minisatellite.

A non-reproductive cell; a cell that divides by mitosis.

A hypothesis which holds that the spread of agriculture into Europe was accompanied by a large-scale movement of human populations.

A promoter that directs relatively few productive initiations per unit time.

A genome sequencing strategy which combines random shotgun sequencing with a genome map, the latter used to aid assembly of the master sequence.

A gene, cell or organism that displays the typical phenotype and/or genotype for the species and is therefore adopted as a standard.

A type of DNA-binding domain.

The process by which a single tRNA can decode more than one codon.

Inactivation by methylation of most of the genes on one copy of the X chromosome in a female nucleus.

A technique for determining the three-dimensional structure of a large molecule.

The diffraction of X-rays that occurs during passage through a crystal.

The pattern obtained after diffraction of X-rays through a crystal.

A high-capacity cloning vector constructed from the components of a yeast chromosome.

A technique for identifying proteins that interact with one other.

A conformation of DNA in which the two polynucleotides are wound into a left-handed helix.

A common structural motif for attachment of a protein to a DNA molecule.

A technique that attempts to determine if a DNA fragment contains a gene by hybridizing that fragment to DNA preparations from related species, on the basis that genes have similar sequences in related species and so give positive hybridization signals, whereas the regions between genes have less similar sequences and so do not hybridize.

The cell resulting from fusion of gametes during meiosis.