International Union of Pharmacology. L. Nomenclature and structure-function relationships of CatSper and two-pore channels.

CatSper channels (CatSper1–4) are named after the first putative cation channel of sperm (Quill et al., 2001; Ren et al., 2001). CatSpers are putative six-transmembrane (6TM) voltage-gated Ca -permeant channels and seem to be specific to sperm cells. CatSper1 and 2 are each essential for the hyperactivation of sperm cell motility, which is required for fertility. Sequence identities among these CatSper family members range between 22 and 27% across the ion transport domain (Lobley et al., 2003).