TAFII250 is a bipartite protein kinase that phosphorylates the base transcription factor RAP74.
Some TAF subunits of transcription factor TFIID play a pivotal role in transcriptional activation by mediating protein-protein interactions, whereas other TAFs direct promoter selectivity via protein-DNA recognition. Here, we report that purified recombinant TAFII250 is a protein serine kinase that selectively phosphotylates RAP74 but not other basal transcription factors or common phosphoacceptor proteins. The phosphorylation of RAP74 also occurs in the context of the complete TFIID complex. Deletion analysis revealed that TAFII250 contains two distinct kinase domains each capable of autophosphorylation. However, both the N- and C-terminal kinase domains of TAFII250 are required for efficient transphosphorylation of RAP74 on serine residues. These findings suggest that the targeted phosphorylation of RAP74 by TAFII250 may provide a mechanism for signaling between components within the initiation complex to regulate transcription.
SciCrunch is a data sharing and display platform. Anyone can create a custom portal where they can select searchable subsets of hundreds of data sources, brand their web pages and create their community. SciCrunch will push data updates automatically to all portals on a weekly basis. User communities can also add their own data to scicrunch, however this is not currently a free service.