MECHANISM OF SPERM-OOCYTE INTERACTION DURING FERTILIZATION IN THE SURF CLAM SPISULA SOLIDISSIMA

¹ The Population Council, Center for Biomedical Research, 1230 York Avenue, New York, NY 10021
² Marine Biological Laboratory, Woods Hole, MA 02543 USA

Spisula oocytes were treated with Triton X-100 to investigate sperm receptor(s) on the surface membrane. The study shows that macromolecules with sperm receptor activity reside on the surface membrane of oocytes. The evidence is that: 1.) Triton X-l00 treated oocytes fail to undergo GVBD on exposure to sperm; 2.) Triton X-l00 treated oocytes incubated with oocyte extract are capable of sperm-induced reactivation; 3.) Incubation of sperm with oocyte extract interfered with the fertilizing capability of sperm; 4.) Incubation of oocyte extract with sperm eliminated its ability to reactivate Triton X-l00 treated oocytes to undergo GVBD; 5.) Reactivation of Triton X-l00 treated oocytes is species-specific, i.e., Spisula oocyte extract was active, while Arbacia oocyte extract was inactive; 6.) the lectin that interacts with fucose blocked GVBD induced by sperm.