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Genetics. Jul 1995; 140(3): 1033–1045.
PMCID: PMC1206659

Cis-Effects of Heterochromatin on Heterochromatic and Euchromatic Gene Activity in Drosophila Melanogaster


Chromosomal rearrangements that juxtapose heterochromatin and euchromatin can result in mosaic inactivation of heterochromatic and euchromatic genes. This phenomenon, position effect variegation (PEV), suggests that heterochromatic and euchromatic genes differ in their regulatory requirements. This report describes a novel method for mapping regions required for heterochromatic genes, and those that induce PEV of a euchromatic gene. P transposase mutagenesis was used to generate derivatives of a translocation that variegated for the light(+) (lt(+)) gene and carried the euchromatic white(+) (w(+)) gene on a transposon near the heterochromatin-euchromatin junction. Cytogenetic and genetic analyses of the derivatives showed that P mutagenesis resulted in deletions of several megabases of heterochromatin. Genetic and molecular studies showed that the derivatives shared a euchromatic breakpoint but differed in their heterochromatic breakpoint and their effects on seven heterochromatic genes and the w(+) gene. Heterochromatic genes differed in their response to deletions. The lt(+) gene was sensitive to the amount of heterochromatin at the breakpoint but the heterochromatic 40Fa gene was not. The severity of variegated w(+) phenotype did not depend on the amount of heterochromatin in cis, but varied with local heterochromatic environment. These data are relevant for considering mechanisms of PEV of both heterochromatic and euchromatic genes.

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Selected References

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  • Anderson KV, Jürgens G, Nüsslein-Volhard C. Establishment of dorsal-ventral polarity in the Drosophila embryo: genetic studies on the role of the Toll gene product. Cell. 1985 Oct;42(3):779–789. [PubMed]
  • BAKER WK, REIN A. The dichotornous action of Y chromosomes on the expression of position-effect variegation. Genetics. 1962 Oct;47:1399–1407. [PMC free article] [PubMed]
  • Bonaccorsi S, Lohe A. Fine mapping of satellite DNA sequences along the Y chromosome of Drosophila melanogaster: relationships between satellite sequences and fertility factors. Genetics. 1991 Sep;129(1):177–189. [PMC free article] [PubMed]
  • Dimitri P. Cytogenetic analysis of the second chromosome heterochromatin of Drosophila melanogaster. Genetics. 1991 Mar;127(3):553–564. [PMC free article] [PubMed]
  • Dorer DR, Henikoff S. Expansions of transgene repeats cause heterochromatin formation and gene silencing in Drosophila. Cell. 1994 Jul 1;77(7):993–1002. [PubMed]
  • Eberl DF, Duyf BJ, Hilliker AJ. The role of heterochromatin in the expression of a heterochromatic gene, the rolled locus of Drosophila melanogaster. Genetics. 1993 May;134(1):277–292. [PMC free article] [PubMed]
  • Gatti M, Pimpinelli S. Functional elements in Drosophila melanogaster heterochromatin. Annu Rev Genet. 1992;26:239–275. [PubMed]
  • Gatti M, Bonaccorsi S, Pimpinelli S. Looking at Drosophila mitotic chromosomes. Methods Cell Biol. 1994;44:371–391. [PubMed]
  • Hearn MG, Hedrick A, Grigliatti TA, Wakimoto BT. The effect of modifiers of position-effect variegation on the variegation of heterochromatic genes of Drosophila melanogaster. Genetics. 1991 Aug;128(4):785–797. [PMC free article] [PubMed]
  • Henikoff S. A reconsideration of the mechanism of position effect. Genetics. 1994 Sep;138(1):1–5. [PMC free article] [PubMed]
  • Hessler AY. V-Type Position Effects at the Light Locus in Drosophila Melanogaster. Genetics. 1958 May;43(3):395–403. [PMC free article] [PubMed]
  • Hilliker AJ. Genetic analysis of the centromeric heterochromatin of chromosome 2 of Drosophila melanogaster: deficiency mapping of EMS-induced lethal complementation groups. Genetics. 1976 Aug;83(4):765–782. [PMC free article] [PubMed]
  • Karpen GH, Spradling AC. Reduced DNA polytenization of a minichromosome region undergoing position-effect variegation in Drosophila. Cell. 1990 Oct 5;63(1):97–107. [PMC free article] [PubMed]
  • Lee CS, Curtis D, McCarron M, Love C, Gray M, Bender W, Chovnick A. Mutations affecting expression of the rosy locus in Drosophila melanogaster. Genetics. 1987 May;116(1):55–66. [PMC free article] [PubMed]
  • Levis R, Hazelrigg T, Rubin GM. Separable cis-acting control elements for expression of the white gene of Drosophila. EMBO J. 1985 Dec 16;4(13A):3489–3499. [PMC free article] [PubMed]
  • Lohe AR, Hilliker AJ, Roberts PA. Mapping simple repeated DNA sequences in heterochromatin of Drosophila melanogaster. Genetics. 1993 Aug;134(4):1149–1174. [PMC free article] [PubMed]
  • McCarron MY, Duttaroy A, Doughty GA, Chovnick A. P-element transposase induces male recombination in Drosophila melanogaster. Genet Res. 1989 Oct;54(2):137–141. [PubMed]
  • Pimpinelli S, Dimitri P. Cytogenetic analysis of segregation distortion in Drosophila melanogaster: the cytological organization of the Responder (Rsp) locus. Genetics. 1989 Apr;121(4):765–772. [PMC free article] [PubMed]
  • Pimpinelli S, Berloco M, Fanti L, Dimitri P, Bonaccorsi S, Marchetti E, Caizzi R, Caggese C, Gatti M. Transposable elements are stable structural components of Drosophila melanogaster heterochromatin. Proc Natl Acad Sci U S A. 1995 Apr 25;92(9):3804–3808. [PMC free article] [PubMed]
  • Robertson HM, Preston CR, Phillis RW, Johnson-Schlitz DM, Benz WK, Engels WR. A stable genomic source of P element transposase in Drosophila melanogaster. Genetics. 1988 Mar;118(3):461–470. [PMC free article] [PubMed]
  • Schultz J. Variegation in Drosophila and the Inert Chromosome Regions. Proc Natl Acad Sci U S A. 1936 Jan;22(1):27–33. [PMC free article] [PubMed]
  • Spofford JB, DeSalle R. Nucleolus organizer-suppressed position-effect variegation in Drosophila melanogaster. Genet Res. 1991 Jun;57(3):245–255. [PubMed]
  • Talbert PB, LeCiel CD, Henikoff S. Modification of the Drosophila heterochromatic mutation brownDominant by linkage alterations. Genetics. 1994 Feb;136(2):559–571. [PMC free article] [PubMed]
  • Tartof KD, Hobbs C, Jones M. A structural basis for variegating position effects. Cell. 1984 Jul;37(3):869–878. [PubMed]
  • Wakimoto BT, Hearn MG. The effects of chromosome rearrangements on the expression of heterochromatic genes in chromosome 2L of Drosophila melanogaster. Genetics. 1990 May;125(1):141–154. [PMC free article] [PubMed]

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