The mammalian zona pellucida, which mediates species-specific sperm binding, induction of the acrosome reaction and prevents post-fertilization polyspermy, is composed of three to four glycoproteins, ZP1, ZP2, ZP3, and ZP4. ZP4 may act as a sperm receptor.
Belongs to the ZP domain family. ZPB subfamily. Contains 1 P-type (trefoil) domain. Contains 1 ZP domain.
The ZP domain is involved in the polymerization of the ZP proteins to form the zona pellucida.
Proteolytically cleaved before the transmembrane segment to yield the secreted ectodomain incorporated in the zona pellucida.
Secreted > extracellular space > extracellular matrix and Cell membrane.