Zona pellucida glycoprotein 2 (ZP2)

Zona pellucida glycoprotein 2 (ZP2) is one of the principal glycoprotein constituents of the zona pellucida, a specialized extracellular matrix surrounding the mammalian oocyte and early embryo[1][2][3]. ZP2 plays a crucial role in mediating the interaction between sperm and egg by functioning as a **secondary sperm receptor**, binding to acrosome-reacted spermatozoa and being essential for oocyte-sperm recognition and fertilization[1][2][3][7]. After fertilization, ZP2 is cleaved by ovastacin, preventing further sperm from binding and thereby serving as a block to polyspermy[1]. The absence of ZP2 disrupts the formation of a stable zona matrix and leads to female infertility in mice, with human pathogenic variants also implicated in infertility and oocyte maturation arrest[2][7]. ZP2 has a conserved ZP domain and is glycosylated; it is often referred to as part of the zona pellucida glycoprotein family, together with ZP1, ZP3, and ZP4 in humans[1][2][3][7]. There is currently no evidence that ZP2 is a direct drug target, nor are there drugs or biomarkers clinically associated with ZP2 modulation.

Other names

Zona pellucida sperm-binding protein 2Processed zona pellucida sperm-binding protein 2ZPAZp-2zona pellucida 2OOMD6OZEMA6zona pellucida protein Azona pellucida glycoprotein 2 (sperm receptor)zona pellucida glycoprotein ZP2