The CDK9 tail determines the reaction pathway of positive transcription elongation factor b.
Baumli, S., Hole, A.J., Wang, L.Z., Noble, M.E., Endicott, J.A.(2012) Structure 20: 1788-1795
- PubMed: 22959624 
- DOI: 10.1016/j.str.2012.08.011
- Primary Citation of Related Structures:  
4EC8, 4EC9 - PubMed Abstract: 
CDK9, the kinase of positive transcription elongation factor b (P-TEFb), stimulates transcription elongation by phosphorylating RNA polymerase II and transcription elongation factors. Using kinetic analysis of a human P-TEFb complex consisting of CDK9 and cyclin T, we show that the CDK9 C-terminal tail sequence is important for the catalytic mechanism and imposes an ordered binding of substrates and release of products ...