Endonuclease that cleaves polypeptidyl-tRNAs downstream of the ribosome-associated quality control (RQC) pathway to release incompletely synthesized polypeptides for degradation (PubMed:29632312, PubMed:30244831, PubMed:31011209). The RQC pathway disassembles aberrantly stalled translation complexes to recycle or degrade the constituent parts (PubMed:29632312, PubMed:30244831, PubMed:31011209). ANKZF1 acts downstream disassembly of stalled ribosomes and specifically cleaves off the terminal 3′-CCA nucleotides universal to all tRNAs from polypeptidyl-tRNAs, releasing (1) ubiquitinated polypeptides from 60S ribosomal subunit for degradation and (2) cleaved tRNAs (PubMed:31011209). ANKZF1-cleaved tRNAs are then repaired and recycled by ELAC1 and TRNT1 (PubMed:31011209, PubMed:32075755). Also plays a role in the cellular response to hydrogen peroxide and in the maintenance of mitochondrial integrity under conditions of cellular stress (PubMed:28302725).