Cation channel sperm-associated auxiliary subunit zeta (CATSPERZ)

Cation channel sperm-associated auxiliary subunit zeta (CATSPERZ) is a protein encoded by the CATSPERZ gene (also known as TEX40, C11orf20) and functions as an essential auxiliary component of the CatSper calcium channel complex in sperm[1][2][3]. CATSPERZ is localized to the principal piece of the sperm flagellum, where it is required for the assembly, structural organization, and linear continuity of the quadrilateral nanodomains of the CatSper channel, which are necessary for efficient calcium influx and hyperactivation of sperm motility essential for fertilization[1][3]. Genetic disruption of CATSPERZ reduces CatSper calcium current and severely impairs sperm rheotactic navigation and fertilizing ability, leading to male subfertility[3]. CATSPERZ acts as a major scaffolding/checkpoint protein in channel assembly, stabilizes partner subunits (such as CATSPER4), and is required for channel dimerization and trafficking to the sperm tail[2]. It is highly specific to testis and sperm, with defects predominately affecting male reproductive health[1][3]. No drugs or clinical modulators are currently reported for this target, but its essential role in sperm function positions it as a potential contraceptive or infertility biomarker candidate[1][3].

Other names

CATSPERZC11orf20TEX40CatSper-zetaCatSperzetaDKFZP566E164Testis-expressed protein 40testis-expressed sequence 40 proteincation channel sperm-associated auxiliary subunit zetatestis expressed 40