Micropeptide that acts as a regulator of DNA repair both by preventing KLHL15-mediated ubiquitination and degradation of RBBP8/CtIP, and by promoting the poly-ADP-ribosyltransferase activity of PARP1 (PubMed:35219381). Prevents KLHL15-mediated ubiquitination of RBBP8/CtIP by competitively blocking the association between KLHL15 and RBBP8/CtIP (PubMed:35219381). Recruited to DNA damage sites via association with poly-ADP-ribose chains, and enhances the poly-ADP- ribosyltransferase activity of PARP1 (PubMed:35219381). . This is the function of MARCHF6-DT (MARCHF6 divergent transcript, Ensembl gene identifier ENSG00000259802).