3'-exoribonuclease that has a preference for poly(A) tails of mRNAs, thereby efficiently degrading poly(A) tails (PubMed:27515512). Exonucleolytic degradation of the poly(A) tail is often 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 (PubMed:27515512). May act as a regulator of multipotency in embryonic stem cells (By similarity). Is a critical factor for proper spermatogenesis, involved in pre-piRNAs processing to generate mature piRNAs (PubMed:34347949). Exonucleolytic cleavage of poly(A) to 5'-AMP. Localizes mainly in the endoplasmic reticulum (PubMed:27515512). The disease is caused by variants affecting the gene represented in this entry. Belongs to the CAF1 family.