Activated RNA polymerase II transcriptional coactivator p15 (PC4)

Activated RNA polymerase II transcriptional coactivator p15 (PC4, also called SUB1) is a multifunctional nuclear protein acting as a transcriptional coactivator and single-stranded DNA-binding protein. SUB1 regulates multiple steps of the transcription cycle, mediates interactions between activators and the basal transcription machinery, and influences chromatin accessibility. It is essential for promoter accessibility, genome stability, and repair of various forms of DNA damage. SUB1 is involved in co-transcriptional mRNA processing and the cellular response to genotoxic stress. Aberrant expression and activity of SUB1 have been implicated in cancer progression—by upregulating oncogenes and downregulating tumor suppressors—as well as in atherosclerosis and inflammatory diseases, where it acts as a master regulator of Toll-like receptor signaling, driving proinflammatory polarization and lesion development. These properties make SUB1 both a potential biomarker for aggressive disease and a candidate therapeutic target in oncology and cardiovascular disease

Other names

SUB1PC4P15p14SUB1 homologtranscriptional regulatorSUB1 regulator of transcription

Potential therapies would involve modulation of transcriptional coactivator activity, inhibition of target binding to key promoters, or indirectly modulating proinflammatory signaling via the SUB1/IRF1 axis