Glyceraldehyde-3-phosphate dehydrogenase, spermatogenic (GAPDHS) (GAPDHS)

Glyceraldehyde-3-phosphate dehydrogenase, spermatogenic (GAPDHS) is a sperm-specific glycolytic enzyme that serves as a critical component of the ATP production machinery in mammalian spermatozoa. Unlike the somatic isoform (GAPDH), GAPDHS is localized exclusively to the principal piece of the sperm flagellum, where it is tethered to the fibrous sheath. It catalyzes the conversion of glyceraldehyde-3-phosphate to 1,3-bisphosphoglycerate, a key step in the glycolytic pathway which provides the majority of the ATP required for flagellar propulsion and hyperactivated motility. Genetic deletion or pharmacological inhibition of GAPDHS leads to a profound depletion of sperm ATP levels, resulting in a complete loss of progressive motility (asthenozoospermia) and male infertility, without affecting spermatogenesis or hormonal balance. Due to its unique expression pattern and essential role in sperm energetics, GAPDHS is a high-priority target for the development of non-hormonal, reversible male contraceptives. Current research focuses on identifying small-molecule inhibitors that selectively target the sperm-specific isoform to avoid systemic metabolic toxicity.

Other names

Sperm cell ATP production machinerySperm-specific glycolytic pathwayGAPDSGAPD2Sperm-specific glyceraldehyde-3-phosphate dehydrogenase

Inhibition of sperm-specific glycolytic enzymes to deplete flagellar ATP levels and halt sperm motility.