Direct targeting and regulation of RNA polymerase II by cell signaling kinases

Abstract

Distinct phosphorylation marks are placed on the carboxyl-terminal domain (CTD) of RNA polymerase II (Pol II) during different stages of gene transcription. These phospho-CTD marks function as a molecular recognition code for the recruitment of stage-specific effector proteins. Querying ~80% of the human kinome, we identified 117 kinases that phosphorylate the CTD with a high degree of positional selectivity. The unifying characteristic linking these diverse kinases is that they selectively regulate Pol II at signal-responsive genes. An example of such "direct-at-gene" Pol II regulation is displayed by epidermal growth factor receptor (EGFR), a cell surface receptor tyrosine kinase. More broadly, our atlas of CTD kinases implicates Pol II as a direct regulatory end point for signal-transducing kinases that govern cellular physiology and contribute to the etiology of numerous diseases.