The Steap proteins are metalloreductases BLOOD Ohgami, R. S., Campagna, D. R., McDonald, A., Fleming, M. D. 2006; 108 (4): 1388-1394

Abstract

Iron and copper are essential for all organisms, assuming critical roles as cofactors in many enzymes. In eukaryotes, the transmembrane transport of these elements is a highly regulated process facilitated by the single electron reduction of each metal. Previously, we identified a mammalian ferrireductase, Steap3, critical for erythroid iron homeostasis. Now, through homology, expression, and functional studies, we characterize all 4 members of this protein family and demonstrate that 3 of them, Steap2, Steap3, and Steap4, are not only ferrireductases but also cupric reductases that stimulate cellular uptake of both iron and copper in vitro. Finally, the pattern of tissue expression and subcellular localization of these proteins suggest they are physiologically relevant cupric reductases and ferrireductases in vivo.

View details for DOI 10.1182/blood-2006-02-003681

View details for Web of Science ID 000239698800047

View details for PubMedID 16609065