Enables heme binding activity. Acts upstream of or within several processes, including activation of cysteine-type endopeptidase activity involved in apoptotic process by cytochrome c; hydrogen peroxide metabolic process; and regulation of protein binding activity. Located in cytosol and mitochondrion. Is expressed in several structures, including central nervous system; jaw; limb; metanephros; and spiral ligament. Human ortholog(s) of this gene implicated in cholangiocarcinoma; lung non-small cell carcinoma; pancreatic cancer; and thrombocytopenia. Orthologous to human CYCS (cytochrome c, somatic). [provided by Alliance of Genome Resources, Apr 2022]