Displays thioredoxin reductase, glutaredoxin and glutathione reductase activities. Catalyzes disulfide bond isomerization. Promotes disulfide bond formation between GPX4 and various sperm proteins and may play a role in sperm maturation by promoting formation of sperm structural components (By similarity).
Subcellular locations: Cytoplasm, Nucleus, Microsome, Endoplasmic reticulum
Detected in cytoplasm and nucleus in late spermatids.