Function
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. ZP3 is essential for zona matrix formation. In pig, does not seem to have a sperm-binding activity by itself but may increase sperm-binding activity of ZPB.
Sequence
MAPSWRFFVCFLLWGGTELCSPQPVWQDEGQRLRPSKPPTVMVECQEAQLVVIVSKDLFGTGKLIRPADLSLGPAKCEPLVSQDTDAVVRFEVGLHECGSSLQVTDDALVYSTFLRHDPRPAGNLSILRTNRAEVPIECHYPRQGNVSSWAILPTWVPFRTTVFSEEKLVFSLRLMEENWSAEKMTPTFQLGDRAHLQAQVHTGSHVPLRLFVDHCVATLTPDWNTSPSHTIVDFHGCLVDGLTEASSAFKAPRPGPETLQFTVDVFHFANDSRNTIYITCHLKVTPADRVPDQLNKACSFSKSSNRWSPVEGPAVICRCCHKGQCGTPSLSRKLSMPKRQSAPRSRRHVTDEADVTVGPLIFLGKTSDHGVEGSTSSPTSVMVGLGLATVVTLTLATIVLGVPRRRRAAAHLVCPVSASQ