3D4C ZP-N DOMAIN OF MAMMALIAN SPERM RECEPTOR ZP3 (CRYSTAL FORM I) CELL ADHESION, FERTILIZATION, OOCYTE, EGG COAT, ZONA PELLUCIDA, VITELLINE ENVELOPE, ZP DOMAIN, EGG-SPERM INTERACTION, SPECIES-SPECIFIC GAMETE RECOGNITION, SPECIATION, BIODIVERSITY, INFERTILITY, EXTRACELLULAR MATRIX, IMMUNOGLOBULIN-LIKE FOLD, GLYCOPROTEIN, RECEPTOR, SECRETED, TRANSMEMBRANE