Human STEAP family member 4,Steap4 ELI

Integral membrane protein that functions as NADPH-dependent ferric-chelate reductase, using NADPH from one side of the membrane to reduce a Fe(3+) chelate that is bound on the other side of the membrane.

Mediates sequential transmembrane electron transfer from NADPH to FAD and onto heme, and finally to the Fe(3+) chelate (PubMed:30337524).

Can also reduce Cu(2+) to Cu(1+) (By similarity).

Plays a role in systemic metabolic homeostasis, integrating inflammatory and metabolic responses (By similarity).

Associated with obesity and insulin-resistance (PubMed:18430367, PubMed:18381574).

Involved in inflammatory arthritis, through the regulation of inflammatory cytokines (PubMed:19660107).

Inhibits anchorage-independent cell proliferation (PubMed:19787193).

{ECO:0000250|UniProtKB:Q923B6, ECO:0000269|PubMed:18381574, ECO:0000269|PubMed:18430367, ECO:0000269|PubMed:19660107, ECO:0000269|PubMed:19787193, ECO:0000269|PubMed:30337524}.