This enzyme is required for electron transfer from NADP to cytochrome p450 in microsomes. It can also provide electron transfer to heme oxygenase and cytochrome b5 (By similarity). May function to clear the olfactory organ (antennae) from accumulating chemicals. NADPH + 2 oxidized [cytochrome P450] = H(+) + NADP(+) + 2 reduced [cytochrome P450] Binds 1 FAD per monomer. Binds 1 FMN per monomer. Interacts with sturkopf. High in antennae. Embryos and adults. Belongs to the NADPH--cytochrome P450 reductase family. In the N-terminal section; belongs to the flavodoxin family. In the C-terminal section; belongs to the flavoprotein pyridine nucleotide cytochrome reductase family.