Poly(A)-specific ribonuclease PARN (PARN)

3'-exoribonuclease which has a preference for poly(A) tails of mRNAs, thereby efficiently degrading poly(A) tails. Exonucleolytic degradation of the poly(A) tail is frequently the first step in the decay of eukaryotic mRNAs and is also used to silence certain maternal mRNAs translationally during oocyte maturation and early embryonic development.

Interacts with both the 3'-end poly(A) tail and the 5'-end cap arrangement during degradation, the interaction with the cap structure needing an efficient degradation of poly(A) tails. Involved in nonsense-mediated mRNA decay, a critical process of selective degradation of mRNAs that contain premature stop codons.