Skip to main content
. Author manuscript; available in PMC: 2016 Jun 18.
Published in final edited form as: Mol Cell. 2015 Jun 18;58(6):959–969. doi: 10.1016/j.molcel.2015.01.037

Figure 3. RNA regulation by PARPs during normal conditions.

Figure 3

(a) PARP1 mediated poly(ADP-ribosyl)ation of histones results in chromatin relaxation and increased accessibility for transcription. During maturation of pre-mRNA, components of the splicing machinery are ADP-ribosylated. The nucleolus, a nuclear structure mainly composed of RNA and RNA binding proteins, is held together by a dense meshwork of poly(ADP-ribose) generated by PARP1. This keeps the components involved in ribosome biogenesis in close proximity to one another and facilitates assembly. In addition, poly(ADP-ribosyl)ation is also required for the shuttling of protein components between the nucleolus and Cajal bodies.

(b)Cytoplasmic RNA regulation by PARPs. PARP7, PARP10, PARP12 and PARP13 are involved in translation inhibition, e.g. by ADP-ribosylation of the elongation factor EF2 and ribosomal proteins. PARP13 and PARP14 promote degradation of specific transcripts by targeting these transcripts to the cellular RNA decay machinery. PARP13 can also inhibit microRNA mediated mRNA silencing.