Elongin B (ELOB)

Elongin B is a small regulatory protein encoded by the ELOB gene that forms a central component of the Elongin (SIII) complex, which is crucial for stimulating transcription elongation by RNA polymerase II by preventing transient pausing during gene transcription[2][3][5][7][10]. Elongin B, together with Elongin C, serves as a regulatory cofactor: the pair binds to the active Elongin A (or A2 in testis) and modulates its activity. Beyond its role in transcription, Elongin B acts as a core adaptor in multiple E3 ubiquitin ligase complexes—most notably by linking SOCS box-containing substrate recognition proteins (such as von Hippel–Lindau tumor suppressor, SOCS proteins, and various viral proteins) to cullin-RING ubiquitin ligase scaffolds, thus mediating selective protein ubiquitination and degradation in processes like oxygen sensing, cytokine signaling, and host-pathogen interactions[1][6][8]. High expression of Elongin B has been noted in cancers such as breast cancer, where it is associated with poor prognosis and tumor progression via the degradation of oncoproteins (e.g., p14/ARF)[4]. Its essential function in both transcription and ubiquitin-mediated protein degradation makes Elongin B a potential therapeutic target in oncology and virology, though targeting strategies are at an early stage and may pose risks due to its fundamental cellular roles[4][8].

Other names

Elongin-BTranscription elongation factor B polypeptide 2TCEB2

Inhibition of ELOB could theoretically block E3 ubiquitin ligase activity, alter protein degradation (especially of oncoproteins like HIF-1α, p14/ARF), interfere with cancer-promoting pathways, or disrupt viral immune evasion[1][4][8].