Sperm lytic activity and its relation to fertilization in the frogRana pipiens

✍ Scribed by Elinson, Richard P.

• Publisher: John Wiley and Sons
• Year: 1971
• Tongue: English
• Weight: 751 KB
• Volume: 177
• Category: Article
• ISSN: 0022-104X
• DOI: 10.1002/jez.1401770208

✦ Synopsis

Abstract

Fully jellied frog oocytes lost their fertilizability with time after being placed in 10% Ringer's, the normal medium for fertilization. One stage in the loss of fertilizability was the appearance of blebs on the surface of the unfertilized oocytes. The blebs resulted from the weakening or lysis of the vitelline coat surrounding the oocyte by the sperm and the subsequent failure of sperm penetration into the oocyte.

Both blebbing and fertilization were inhibited by soybean trypsin inhibitor. The inhibitor did not harm the sperm or the oocyte, or prevent the sperm from travelling through the jelly. The lytic activity was therefore necessary but not sufficient for fertilization. The lytic activity appeared to be induced by the jelly surrounding the frog oocyte.

Sperm of the toad Bufo americanus did not fertilize oocytes of Rana pipiens but did cause blebbing. The blebbing was inhibited by soybean trypsin inhibitor.