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ELOB elongin B [ Homo sapiens (human) ]

Gene ID: 6923, updated on 6-Nov-2022


Official Symbol
ELOBprovided by HGNC
Official Full Name
elongin Bprovided by HGNC
Primary source
See related
Ensembl:ENSG00000103363 MIM:600787; AllianceGenome:HGNC:11619
Gene type
protein coding
RefSeq status
Homo sapiens
Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae; Homo
Also known as
This gene encodes the protein elongin B, which is a subunit of the transcription factor B (SIII) complex. The SIII complex is composed of elongins A/A2, B and C. It activates elongation by RNA polymerase II by suppressing transient pausing of the polymerase at many sites within transcription units. Elongin A functions as the transcriptionally active component of the SIII complex, whereas elongins B and C are regulatory subunits. Elongin A2 is specifically expressed in the testis, and capable of forming a stable complex with elongins B and C. The von Hippel-Lindau tumor suppressor protein binds to elongins B and C, and thereby inhibits transcription elongation. Two alternatively spliced transcript variants encoding different isoforms have been described for this gene. Pseudogenes have been identified on chromosomes 11 and 13. [provided by RefSeq, Aug 2008]
Ubiquitous expression in testis (RPKM 67.4), adrenal (RPKM 41.2) and 25 other tissues See more
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Genomic context

See ELOB in Genome Data Viewer
Exon count:
Annotation release Status Assembly Chr Location
110 current GRCh38.p14 (GCF_000001405.40) 16 NC_000016.10 (2771414..2777280, complement)
110 current T2T-CHM13v2.0 (GCF_009914755.1) 16 NC_060940.1 (2791632..2797493, complement)
105.20220307 previous assembly GRCh37.p13 (GCF_000001405.25) 16 NC_000016.9 (2821415..2827281, complement)

Chromosome 16 - NC_000016.10Genomic Context describing neighboring genes Neighboring gene SRRM2 antisense RNA 1 Neighboring gene serine/arginine repetitive matrix 2 Neighboring gene serine protease 33 Neighboring gene small nucleolar RNA, H/ACA box 3C

Genomic regions, transcripts, and products


  • Project title: HPA RNA-seq normal tissues
  • Description: RNA-seq was performed of tissue samples from 95 human individuals representing 27 different tissues in order to determine tissue-specificity of all protein-coding genes
  • BioProject: PRJEB4337
  • Publication: PMID 24309898
  • Analysis date: Wed Apr 4 07:08:55 2018


GeneRIFs: Gene References Into Functions

What's a GeneRIF?

HIV-1 interactions

Protein interactions

Protein Gene Interaction Pubs
Tat tat The C-terminal 34 residues (1329-1362) of BRD4 are crucial for interaction with P-TEFb. Overexpression of the BRD4 P-TEFb-interacting domain disrupts the interaction between HIV-1 Tat and P-TEFb PubMed
tat HIV-1 Tat directly interacts with elongin B as demonstrated by Tat-affinity column purification PubMed
Vif vif HIV-1 complexes with TCEB2 (ELOB) PubMed
vif ASK1 inhibits the interaction of HIV-1 Vif with ELOB/C in a dose-dependent manner, whereas no significant change is observed in the binding of Vif with CUL5 or CBFbeta PubMed
vif CUL5/RBX2/ELOB/ELOC/Vif/CBF-beta complex catalyzes polyubiquitin chain formation on A3G in the presence of ubiquitin E2 UBE2R1 (CDC34) or UBCH5b (UBE2D2) PubMed
vif HIV-1 Vif, CBF-beta, CUL5, and ELOB/C form a complex that is required for Vif-mediated downregulation of A3G and A3F. CBF-beta regulates HIV-1 infectivity only in the presence of A3G PubMed
vif An overall crystal structure indicates that the Vif-CBF-beta-CUL5-ELOB-ELOC complex has a U-shape architecture, including the two straight arms Vif-CBF-beta and CUL5 and the bent arm formation between ELOC and CUL5 and Vif interactions PubMed
vif HIV-1 Vif (amino acids 144-149; SLQXLA motif) interacts with cellular proteins Cul5, elongins B and C, and Rbx1 to form an Skp1-Cullin-F-box (SCF)-like complex that allows Vif to interact with APOBEC3G and induce its ubiquitination and degradation PubMed
vif HIV-1 Vif mutants W5S, W21S, W38S, W89S, F112S, and F115S have a reduced ability to interact with CBF-beta, but these Vif hydrophobic residue mutations still interact with EloB PubMed
vif Simultaneous substitution of the three Vif-interacting residues L52, W53, and D55 and the two ELOC-interacting residues P41 and H48 in CUL5 impairs the ability of CUL5 to interact with the Vif-CBF-beta-ELOB-ELOC protein complex PubMed
vif The absence of Vif-CBF-beta reduces the interaction between the CUL5 and the EloC-EloB complex, indicating that the former two proteins have a critical role in promoting assembly of the pentameric complex PubMed
vif The PPLP motif (residues 161-164) of HIV-1 Vif binds to the C-terminal region (residues 101-118) of ElonginB PubMed
vif Overexpression of EloB increases HIV-1 Vif stability in cells. The N-terminal residues 9-14 of EloB are involved in EloB-mediated stability of Vif PubMed
vif The interaction of HIV-1 Vif with EloB/EloC complex is important for the binding of Vif to CBF-beta in cells. The Vif SOCS box mutant (SLQ to AAA) significantly disrupt its interaction with the EloB/EloC complex PubMed
vif The interaction between the HIV-1 Vif PPLP motif (residues 161-164) and the 34-amino-acid C-terminal tail (residues 85-118) of EloB plays a role in promoting recruitment of CBF-beta to the Vif-Cul5 E3 complex PubMed
vif The solubility of HIV-1 Vif is significantly enhanced by co-expression of EloB, EloC, and CBF-beta in vitro PubMed
vif The substitution of Leu64 or Ile66 with serine abolishes the ability of CBF-beta to interact with the Vif-EloB/EloC complex, while the substitution of Thr68 or Tyr69 with alanine has an intermediate effect on the interaction of CBF-beta with the complex PubMed
vif Amino acid residues Vif135-158 have the most binding to the Elongin BC complex and undergo a structural change in the presence of Elongin BC PubMed

Go to the HIV-1, Human Interaction Database

Pathways from PubChem


Products Interactant Other Gene Complex Source Pubs Description

General gene information



Gene Ontology Provided by GOA

Function Evidence Code Pubs
enables protein binding IPI
Inferred from Physical Interaction
more info
enables transcription corepressor binding IPI
Inferred from Physical Interaction
more info
enables ubiquitin protein ligase binding IDA
Inferred from Direct Assay
more info
Component Evidence Code Pubs
part_of Cul2-RING ubiquitin ligase complex IDA
Inferred from Direct Assay
more info
part_of Cul5-RING ubiquitin ligase complex IDA
Inferred from Direct Assay
more info
part_of VCB complex IBA
Inferred from Biological aspect of Ancestor
more info
located_in cytosol TAS
Traceable Author Statement
more info
part_of elongin complex IBA
Inferred from Biological aspect of Ancestor
more info
part_of elongin complex IDA
Inferred from Direct Assay
more info
located_in nucleoplasm TAS
Traceable Author Statement
more info

General protein information

Preferred Names
RNA polymerase II transcription factor SIII p18 subunit
RNA polymerase II transcription factor SIII subunit B
SIII p18
elongin 18 kDa subunit
elongin, 18-kD subunit
epididymis secretory sperm binding protein
transcription elongation factor B (SIII), polypeptide 2 (18kDa, elongin B)
transcription elongation factor B polypeptide 2
transcription elongation factor B subunit 2

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_007108.4NP_009039.1  elongin-B isoform a

    See identical proteins and their annotated locations for NP_009039.1

    Status: REVIEWED

    Transcript Variant: This variant (1) encodes the predominant isoform (a).
    Source sequence(s)
    AC092117, BC013306, DT217333
    Consensus CDS
    B7WPD3, Q15370
    ENSP00000386652.5, ENST00000409906.9
    Conserved Domains (1) summary
    Ubl_ElonginB; ubiquitin-like (Ubl) domain found in transcription elongation factor B (Elongin B) and similar proteins
  2. NM_207013.3NP_996896.1  elongin-B isoform b

    See identical proteins and their annotated locations for NP_996896.1

    Status: REVIEWED

    Transcript Variant: This variant (2) lacks a segment in the 3' region, resulting in a downstream stop codon, compared to variant 1. The resulting isoform (b) has a longer C-terminus, compared to isoform a.
    Source sequence(s)
    AC092117, BC013306, BM700019
    Consensus CDS
    ENSP00000262306.7, ENST00000262306.11
    Conserved Domains (1) summary
    ElonginB; Ubiquitin-like domain of Elongin B

RefSeqs of Annotated Genomes: Homo sapiens Annotation Release 110 details...Open this link in a new tab

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

Reference GRCh38.p14 Primary Assembly


  1. NC_000016.10 Reference GRCh38.p14 Primary Assembly

    2771414..2777280 complement
    GenBank, FASTA, Sequence Viewer (Graphics)

Alternate T2T-CHM13v2.0


  1. NC_060940.1 Alternate T2T-CHM13v2.0

    2791632..2797493 complement
    GenBank, FASTA, Sequence Viewer (Graphics)

Suppressed Reference Sequence(s)

The following Reference Sequences have been suppressed. Explain

  1. NG_001582.3: Suppressed sequence

    NG_001582.3: This RefSeq was permanently suppressed because it is now thought that this gene does encode a protein.