Download MendeleyThr 4 phosphorylation on RNA Pol II occurs at early transcription regulating 3'-end processing.
Moreno, R.Y., Panina, S.B., Irani, S., Hardtke, H.A., Stephenson, R., Floyd, B.M., Marcotte, E.M., Zhang, Q., Zhang, Y.J.(2024) Sci Adv 10: eadq0350-eadq0350
- PubMed: 39241064
- DOI: https://doi.org/10.1126/sciadv.adq0350
- Primary Citation of Related Structures:
9B9L - PubMed Abstract:
RNA polymerase II relies on a repetitive sequence domain (YSPTSPS) within its largest subunit to orchestrate transcription. While phosphorylation on serine-2/serine-5 of the carboxyl-terminal heptad repeats is well established, threonine-4's role remains enigmatic. Paradoxically, threonine-4 phosphorylation was only detected after transcription end sites despite functionally implicated in pausing, elongation, termination, and messenger RNA processing. Our investigation revealed that threonine-4 phosphorylation detection was obstructed by flanking serine-5 phosphorylation at the onset of transcription, which can be removed selectively. Subsequent proteomic analyses identified many proteins recruited to transcription via threonine-4 phosphorylation, which previously were attributed to serine-2. Loss of threonine-4 phosphorylation greatly reduces serine-2 phosphorylation, revealing a cross-talk between the two marks. Last, the function analysis of the threonine-4 phosphorylation highlighted its role in alternative 3'-end processing within pro-proliferative genes. Our findings unveil the true genomic location of this evolutionarily conserved phosphorylation mark and prompt a reassessment of functional assignments of the carboxyl-terminal domain.
Organizational Affiliation:
Department of Molecular Biosciences, University of Texas, Austin, TX, USA.
