The function of ENSG00000125843 (AP5S1, adaptor related protein complex 5 subunit sigma 1) is as follows. As part of AP-5, a probable fifth adaptor protein complex it may be involved in endosomal transport. According to PubMed:20613862, it is required for efficient homologous recombination DNA double-strand break repair. {ECO:0000269|PubMed:20613862, ECO:0000269|PubMed:22022230}.