Role of sperm-surface glycoproteins in gamete recognition in two mouse species

In-vitro fertilization and sperm binding to the zona pellucida within and between Mus musculus (laboratory mouse) and Mus caroli (Asian wild field mouse) were examined. Maximum homologous sperm binding in M. musculus was 12.3 +/- 0.3 spermatozoa bound/egg and in M. caroli, 9.2 +/- 0.2. In heterologous crosses, sperm-zona binding was significantly reduced (M. musculus eggs with M. caroli spermatozoa, 1.9 +/- 0.14; M. caroli eggs with M. musculus spermatozoa, 5.5 +/- 0.2). Homologous sperm-zona interaction was inhibited by different sugars in the two mouse species (M. caroli by alpha-methyl mannose, M. musculus by sialic acid). The data suggest that gamete recognition is highly species specific and that hapten sugars play a significant role in sperm-zona binding.