Cross-Talk of Phosphorylation and Prolyl Isomerization of the C-terminal Domain of RNA Polymerase II

Molecules

S. D. Yogesha¹  Joshua E. Mayfield¹ 

[1] Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA; E-Mails:

关键词: CTD;    RNA polymerase II;    transcription;    prolyl-isomerization;    phosphorylation;    combinatorial regulation;   

DOI  :  10.3390/molecules19021481

来源: mdpi

【 摘 要 】

Post-translational modifications of the heptad repeat sequences in the C-terminal domain (CTD) of RNA polymerase II (Pol II) are well recognized for their roles in coordinating transcription with other nuclear processes that impinge upon transcription by the Pol II machinery; and this is primarily achieved through CTD interactions with the various nuclear factors. The identification of novel modifications on new regulatory sites of the CTD suggests that, instead of an independent action for all modifications on CTD, a combinatorial effect is in operation. In this review we focus on two well-characterized modifications of the CTD, namely serine phosphorylation and prolyl isomerization, and discuss the complex interplay between the enzymes modifying their respective regulatory sites. We summarize the current understanding of how the prolyl isomerization state of the CTD dictates the specificity of writers (CTD kinases), erasers (CTD phosphatases) and readers (CTD binding proteins) and how that correlates to transcription status. Subtle changes in prolyl isomerization states cannot be detected at the primary sequence level, we describe the methods that have been utilized to investigate this mode of regulation. Finally, a general model of how prolyl isomerization regulates the phosphorylation state of CTD, and therefore transcription-coupled processes, is proposed.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.