CIAPIN1 is a cytokine-induced inhibitor of apoptosis with no relation to apoptosis regulatory molecules of the BCL2 or CASP families. Expression of CIAPIN1 is dependent on growth factor stimulation. Component of the cytosolic iron-sulfur (Fe-S) protein assembly (CIA) machinery. Required for the maturation of extramitochondrial Fe-S proteins. Part of an electron transfer chain functioning in an early step of cytosolic Fe-S biogenesis. Electrons are transferred to the Fe-S cluster from NADPH via the FAD- and FMN-containing protein NDOR1.