Zona pellucida glycoprotein 4 (ZP4)

Zona pellucida glycoprotein 4 (ZP4) is one of four major glycoprotein components (alongside ZP1, ZP2, and ZP3) of the zona pellucida—a 5–10 μm extracellular matrix layer produced by the oocyte. ZP4 contributes to the structural properties of the zona pellucida, serves as a sperm receptor, facilitates sperm binding, and induces the acrosome reaction. Its role is critical for preventing polyspermy and for the protection of the embryo prior to implantation. Unlike the mouse model (where ZP4 is absent), other eutherian mammals such as humans express ZP4, which supports the mechanical strength and impermeability of the zona pellucida. Deficiency or absence of ZP4 results in thinner, irregular, and more permeable zonae, leading to reduced fertility, but generally does not affect the early stages of fertilization or blastocyst development in vitro. ZP4 is encoded by the ZP4 gene, which features domains supporting secretion, matrix assembly, and interaction with sperm. Diseases associated with ZP4 include ovarian dysgenesis and prostate cancer; its exact role in disease remains an active topic of research. ZP4 is not a conventional therapeutic target and has no known interacting drugs or established biomarker status in clinical practice.

Other names

ZP4Zona pellucida sperm-binding protein 4Processed zona pellucida sperm-binding protein 4ZPBZp-4ZPB2ZP1BZona pellucida protein BZBP

Not applicable, because there are no drugs targeting ZP4