Multisubunit RNA Polymerase Cleavage Factors Modulate the Kinetics and Energetics of Nucleotide Incorporation: An RNA Polymerase I Case Study.

ABSTRACT: All cellular RNA polymerases are influenced by protein factors that stimulate RNA polymerase-catalyzed cleavage of the nascent RNA. Despite divergence in amino acid sequence, these so-called "cleavage factors" appear to share a common mechanism of action. Cleavage factors associate with the polymerase through a conserved structural element of the polymerase known as the secondary channel or pore. This mode of association enables the cleavage factor to reach through the secondary channel into the polymerase active site to reorient the active site divalent metal ions. This reorientation converts the polymerase active site into a nuclease active site. Interestingly, eukaryotic RNA polymerases I and III (Pols I and III, respectively) have incorporated their cleavage factors as bona fide subuni

SUBMITTER: Appling FD 

PROVIDER: S-EPMC6400273 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature