Brd4 and HEXIM1: multiple roles in P-TEFb regulation and cancer.

Abstract

Bromodomain-containing protein 4 (Brd4) and hexamethylene bisacetamide (HMBA) inducible protein 1 (HEXIM1) are two opposing regulators of the positive transcription elongation factor b (P-TEFb), which is the master modulator of RNA polymerase II during transcriptional elongation. While Brd4 recruits P-TEFb to promoter-proximal chromatins to activate transcription, HEXIM1 sequesters P-TEFb into an inactive complex containing the 7SK small nuclear RNA. Besides regulating P-TEFb's transcriptional activity, recent evidence demonstrates that both Brd4 and HEXIM1 also play novel roles in cell cycle progression and tumorigenesis. Here we will discuss the current knowledge on Brd4 and HEXIM1 and their implication as novel therapeutic options against cancer.

• Authors: Ruichuan Chen, Jasper H N Yik, Qiao Jing Lew, Sheng-Hao Chao
• Journal: BioMed research international (Biomed Res Int) Vol. 2014 Pg. 232870 ( 2014) ISSN: 2314-6141 [Electronic] United States
• PMID: 24592384 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Review)

Chemical References

• RNA-Binding Proteins
• Transcription Factors
• Positive Transcriptional Elongation Factor B

Topics

• Amino Acid Sequence
• Humans
• Models, Biological
• Molecular Sequence Data
• Neoplasms (metabolism)
• Positive Transcriptional Elongation Factor B (metabolism)
• RNA-Binding Proteins (metabolism)
• Transcription Factors (chemistry, metabolism)