Cytochrome b, Ascorbate Dependent Protein 3 (CYBASC3)

CYBASC3 Contains 1 cytochrome b561 domain. Ferric-chelate reductase that reduces Fe3+ to Fe2+ before its transport from the endosome to the cytoplasm. Probably uses ascorbate as electron donor.

Cytochrome b561 is a major transmembrane protein that is specific to catecholamine and neuropeptide secretory vesicles of the adrenal medulla, pituitary gland, and other neuroendocrine tissues. This 30-kD cytochrome is present in both the small synaptic vesicles and the large dense core vesicles (chromaffin granules) of the tissues. Its role is to supply reducing equivalents to 2 monooxygenases, dopamine beta-hydroxylase in chromaffin granules and peptidylglycine alpha-amidating monooxygenase in neurosecretory vesicles.