As part of AP-5, a probable fifth adaptor protein complex it may be involved in endosomal transport. According to PubMed:20613862 it is a putative helicase required for efficient homologous recombination DNA double-strand break repair. {ECO:0000269|PubMed:20613862, ECO:0000269|PubMed:22022230}. This is the function of AP5Z1 (adaptor related protein complex 5 subunit zeta 1, Ensembl gene identifier ENSG00000242802).