Quick Reference

Type I membrane glycoproteins (PH-30, ADAMs) in sperm membrane that are members of the ADAM family and bind to an integrin on the egg membrane, thus mediating sperm–egg adhesion. They are heterodimers; the α subunit (probably ADAM20, 726 aa, in humans, ADAM1 being a pseudogene) has homology to viral fusion peptides, the β subunit (ADAM2, 735 aa) has a tripeptide sequence involved in integrin binding.

Subjects: Medicine and Health.

Reference entries