The function of PCSK1 (proprotein convertase subtilisin/kexin type 1, ENSG00000175426) is as follows. Involved in the processing of hormone and other protein precursors at sites comprised of pairs of basic amino acid residues. Substrates include POMC, renin, oxytocin, vasopressin, enkephalin, dynorphin, somatostatin, insulin and AGRP. .