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Nelfb negative elongation factor complex member B [ Mus musculus (house mouse) ]

Gene ID: 58202, updated on 12-May-2024


Official Symbol
Nelfbprovided by MGI
Official Full Name
negative elongation factor complex member Bprovided by MGI
Primary source
See related
Ensembl:ENSMUSG00000013465 AllianceGenome:MGI:1931035
Gene type
protein coding
RefSeq status
Mus musculus
Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; Eutheria; Euarchontoglires; Glires; Rodentia; Myomorpha; Muroidea; Muridae; Murinae; Mus; Mus
Also known as
Cobra1; Nelf-b; A730008L03Rik
This gene encodes subunit B of a metazoan-specific, four-subunit protein complex that regulates promoter-proximal pausing of RNA polymerase II. RNA polymerase II pausing is thought to be important for coordination of gene transcription during embryonic development and stress responses. Consistently, disruption of this gene in mouse causes inner cell mass deficiency and embryonic lethality. In addition, this gene is required for maintenance of mouse embryonic stem cells by preventing expression of developmental genes. In adult mice, conditional deletion of this gene results in cardiomyopathy and impaired response to cardiac stress. Multiple protein isoforms are encoded through the use of a non-AUG (CUG) initiation codon and an alternative downstream AUG initiation codon. In addition, alternative splicing results in multiple transcript variants. [provided by RefSeq, Jul 2015]
Ubiquitous expression in limb E14.5 (RPKM 19.3), CNS E11.5 (RPKM 18.0) and 28 other tissues See more
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Genomic context

See Nelfb in Genome Data Viewer
2 A3; 2 17.06 cM
Exon count:
Annotation release Status Assembly Chr Location
RS_2024_02 current GRCm39 (GCF_000001635.27) 2 NC_000068.8 (25089724..25101501, complement)
108.20200622 previous assembly GRCm38.p6 (GCF_000001635.26) 2 NC_000068.7 (25199712..25211489, complement)

Chromosome 2 - NC_000068.8Genomic Context describing neighboring genes Neighboring gene predicted gene, 52547 Neighboring gene STARR-positive B cell enhancer ABC_E3362 Neighboring gene torsin family 4, member A Neighboring gene CapStarr-seq enhancer MGSCv37_chr2:25052129-25052238 Neighboring gene predicted gene, 22572 Neighboring gene sperm tail PG rich repeat containing 3 Neighboring gene ciliary microtubule inner protein 2A Neighboring gene tubulin, beta 4B class IVB

Genomic regions, transcripts, and products


  • Project title: Mouse ENCODE transcriptome data
  • Description: RNA profiling data sets generated by the Mouse ENCODE project.
  • BioProject: PRJNA66167
  • Publication: PMID 25409824
  • Analysis date: n/a


GeneRIFs: Gene References Into Functions

What's a GeneRIF?



Alleles of this type are documented at Mouse Genome Informatics  (MGI)
  • Endonuclease-mediated (2) 
  • Targeted (3)  1 citation

Pathways from PubChem


Products Interactant Other Gene Complex Source Pubs Description

General gene information


Gene Ontology Provided by MGI

Function Evidence Code Pubs
enables RNA binding IEA
Inferred from Electronic Annotation
more info
enables protein binding IPI
Inferred from Physical Interaction
more info
Component Evidence Code Pubs
part_of NELF complex IBA
Inferred from Biological aspect of Ancestor
more info
part_of NELF complex ISO
Inferred from Sequence Orthology
more info
located_in cytoplasm ISO
Inferred from Sequence Orthology
more info
located_in cytosol TAS
Traceable Author Statement
more info
located_in mitochondrial outer membrane TAS
Traceable Author Statement
more info
located_in nucleoplasm ISO
Inferred from Sequence Orthology
more info
located_in nucleus ISO
Inferred from Sequence Orthology
more info

General protein information

Preferred Names
negative elongation factor B
cofactor of BRCA1
negative elongation factor complex member B, Cobra1
ortholog of human cofactor of BRCA1 (COBRA1)

NCBI Reference Sequences (RefSeq)

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RefSeqs maintained independently of Annotated Genomes

These reference sequences exist independently of genome builds. Explain

These reference sequences are curated independently of the genome annotation cycle, so their versions may not match the RefSeq versions in the current genome build. Identify version mismatches by comparing the version of the RefSeq in this section to the one reported in Genomic regions, transcripts, and products above.

mRNA and Protein(s)

  1. NM_001310157.1NP_001297086.1  negative elongation factor B isoform 2

    See identical proteins and their annotated locations for NP_001297086.1

    Status: REVIEWED

    Transcript Variant: This variant (2) differs in the 5' UTR and uses alternate splice sites in the 5' coding region, which results in use of a downstream start codon compared to variant 1. It encodes isoform 2, which has a shorter N-terminus than isoform 1.
    Source sequence(s)
    AI843129, AK173124, AL732309, CJ100279, CX241076
    A0A0X1KG62, Q69ZP4, Q8C4Y3, Q99J41, Q9JJA5
    Conserved Domains (1) summary
    COBRA1; Cofactor of BRCA1 (COBRA1)
  2. NM_021393.3NP_067368.3  negative elongation factor B isoform 1

    Status: REVIEWED

    Transcript Variant: This variant (1) represents the longer isoform (1), which is translated using a non-AUG (CUG) start codon.
    Source sequence(s)
    AI843129, AK173124, AL732309, CJ100279
    Consensus CDS
    ENSMUSP00000057731.10, ENSMUST00000059849.15
    Conserved Domains (1) summary
    COBRA1; Cofactor of BRCA1 (COBRA1)

RefSeqs of Annotated Genomes: GCF_000001635.27-RS_2024_02

The following sections contain reference sequences that belong to a specific genome build. Explain

Reference GRCm39 C57BL/6J


  1. NC_000068.8 Reference GRCm39 C57BL/6J

    25089724..25101501 complement
    GenBank, FASTA, Sequence Viewer (Graphics)