[Term] id: PR:000000669 name: cation channel sperm-associated protein 1 def: "A CatSper channel protein that is a translation product of the human CATSPER1 gene or a 1:1 ortholog thereof. In mammals, four CatSper ion channel subunit genes (CatSpers 1-4) are required for sperm cell hyperactivation and male fertility. The four proteins assemble (presumably as a tetramer) to form a sperm-specific, alkalinization-activated Ca(2+)-selective channel. CatSper channels seem to require auxiliary subunits, such as CatSperB (PR:000000672). In common with other channels, CatSper1 proteins have an architecture consisting of six transmembrane domains (S1-S6), arranged in a voltage sensor (S1-S4) and pore modules (S5-P-S6), and with both N and C termini on the intracellular side of the membrane. Unique to this class is the His-rich N terminus that seems to be involved the pH sensitivity of the channel calcium currents." [PRO:CNA] comment: Category=gene. synonym: "CATSPER1" EXACT PRO-short-label [PRO:DNx] synonym: "CatSper1" EXACT [] synonym: "CatSper" BROAD [PRO:DAN] xref: IUPHARobj:388 property_value: has_archetype PR:Q8NEC5 is_a: PR:000044645 ! CatSper channel protein