Poster abstracts

Poster number 34 submitted by Benjamin Pastore

The exonuclease DISL-2 degrades U-tailed piRNAs undergoing target directed piRNA decay

Benjamin Pastore (The Ohio State Biochemistry Program, Department of Biological Chemistry and Pharmacology, The Center for RNA Biology, The Ohio State University), Hannah L. Hertz (Department of Biological Chemistry and Pharmacology, The Center for RNA Biology, The Ohio State University), Ian F. Price (The Ohio State Biochemistry Program, Department of Biological Chemistry and Pharmacology, The Center for RNA Biology, The Ohio State University)

Abstract:
Piwi interacting RNAs (piRNAs) are a class of small regulatory RNA that suppress the expression of transposable elements and promotes fertility in nearly all animals. Maturation of piRNAs involves pre-piRNA trimming by the exonuclease PARN-1, followed by 2′-O-methylation at their 3’ termini via HENN-1. Proper maturation of piRNAs during their biogenesis protect piRNAs from target directed tailing and degradation. To identify protein co-factors implicated in piRNA tailing and decay we preformed proximity labeling of PIWI Argonaute protein PRG-1 and identified interactions with the poly(U)-polymerase CDE-1 and exonuclease DISL-2. We find that mutants deficient for CDE-1 experience a loss of mono-uridine tailing on piRNAs compared to that in wild type, whereas mutants deficient for DISL-2 accumulate piRNAs with mono-, di- and tri-uridine tails. Together, our findings suggest that piRNAs undergoing target directed decay are uridylated by CDE-1 and degraded by DISL-2.

References:
Pastore, B., Price, I.F., Hertz, H.L., Tang, W. (2021) pre-piRNA trimming and 2′-O-methylation protect piRNAs from 3’ tailing and degradation. Cell Reports. 36, doi: 10.1016/j.celrep.2021.109640.

Gainetdinov I, Colpan C, Cecchini K, Arif A, Jouravleva K, Albosta P, Vega-Badillo J, Lee Y, Özata DM, Zamore PD. (2021) Terminal modification, sequence, length, and PIWI-protein identity determine piRNA stability. Mol Cell. 81, doi: 10.1016/j.molcel.2021.09.012.

Keywords: piRNA, RNA interference, Target Directed Decay