Cation channel sperm-associated protein 1 (IPR028746)

Short name: CatSper1

Overlapping homologous superfamilies


Family relationships



CATSPER (cationic channel of sperm) is a complex ion channel that mediates Ca2+ entry in sperm flagellum and is required for sperm hyperactivation and male fertility [PMID: 11595941]. The CATSPER channel consists of four CatSper proteins (CatSper1-4) that form a tetramer surrounding a Ca(2+)-selective pore. In addition to the pore-forming proteins, the CATSPER channel contains auxiliary subunits [PMID: 21224844].

All four CatSper proteins are predicted to contain a common coiled-coil protein-protein interaction domain in their C-terminal tail [PMID: 12932298] and all four are required for male fertility and sperm cell hyperactivated motility [PMID: 17227845]. The CatSper channel of human sperm is activated by progesterone [PMID: 21412339].

This entry represents cation channel sperm-associated protein 1 (CatSper1) [PMID: 14657352].

GO terms

Biological Process

GO:0030317 flagellated sperm motility

Molecular Function

GO:0005227 calcium activated cation channel activity

Cellular Component

GO:0036128 CatSper complex

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.