The importance of cation-independent phospholipase A2 on sperm motility
The first part of fertilization occurs when sperm establish contact with the zona pellucida. Hyperactivated motility provides additional force helping sperm penetrate the zona pellucida. Sperm from mice that do not express Cation-independent phospholipase A2 (iPLA2) have reduced motility and impaired ability to fertilize oocytes, which indicates that iPLA2 plays an important role in spermatozoa. Calcium is a necessary intracellular regulator of sperm motility and affects hyperactivated motility. Cation-independent phospholipase A2 was investigated because it is considered a crucial molecular determinant in the activation of store-operated cation channels and store-operated Ca2+ entry pathway. In one experiment, cation iPLA2 knockout (KO) and wild-type (ICR strain) mouse sperm was used to determine if deletion of iPLA2 affected motility. In another experiment, wild-type mouse sperm were treated with bromoenol lactone (BEL, an inhibitor of iPLA2). Motility was quantified in both experiments by computer analyzed semen analysis (CASA). Our research shows that deletion of iPLA2 in BEL-treatment promoted a higher percentage of motile cells. Also that progressive motility was substantially decreased in KO mice but not on motility. Therefore, we could not readily assess iPLA2's effect on overall motility.
School:
University of Puerto Rico at Bayamón
Department:
Human Biology
Research Advisor:
David Miller
Department of Research Advisor:
Animal Science
Year of Publication:
2005