RNA Regulation by Poly(ADP-Ribose) Polymerases

Posttranscriptional regulation of RNA facilitates the fine-tuning of gene expression. It occurs through multiple pathways that include the nuclear processing of mRNA and its precursors, mRNA silencing, regulation of mRNA decay, and regulation of translation. Poly(ADP-ribose) polymerases (PARPs), enzymes that modify target proteins with ADP-ribose, play important roles in many of the RNA regulatory pathways through multiple mechanisms. For example, RNA-binding PARPs can target specific transcripts for regulation; ADP-ribosylation of RNA-regulatory proteins can alter their localization, activity, or RNA binding; and noncovalent interactions of RNA-binding proteins with poly(ADP-ribose) can affect their function. In addition to regulating RNA during non-stress conditions, PARPs regulate RNA function during cellular stress conditions that are critical for the proper execution of a stress response. In this review, we summarize the current knowledge regarding PARP-dependent regulation of RNAs, and describe how by modulating RNA processing, translation, and decay PARPs impact multiple processes in the cell.