Enables protein binding activity involved in heterotypic cell-cell adhesion; protein homodimerization activity; and signaling receptor binding activity. Involved in fusion of sperm to egg plasma membrane involved in single fertilization; heterotypic cell-cell adhesion; and sperm-egg recognition. Located in acrosomal membrane and plasma membrane. Is integral component of membrane. Orthologous to human IZUMO1 (izumo sperm-egg fusion 1). [provided by Alliance of Genome Resources, Apr 2022]