The "soluble" adenylyl cyclase in sperm mediates multiple signaling events required for fertilization |
| |
Authors: | Hess Kenneth C Jones Brian H Marquez Becky Chen Yanqiu Ord Teri S Kamenetsky Margarita Miyamoto Catarina Zippin Jonathan H Kopf Gregory S Suarez Susan S Levin Lonny R Williams Carmen J Buck Jochen Moss Stuart B |
| |
Affiliation: | Department of Pharmacology, Joan and Sanford Weill Medical College, Graduate School of Medical Sciences of Cornell University, New York, NY 10021, USA. |
| |
Abstract: | Mammalian fertilization is dependent upon a series of bicarbonate-induced, cAMP-dependent processes sperm undergo as they "capacitate," i.e., acquire the ability to fertilize eggs. Male mice lacking the bicarbonate- and calcium-responsive soluble adenylyl cyclase (sAC), the predominant source of cAMP in male germ cells, are infertile, as the sperm are immotile. Membrane-permeable cAMP analogs are reported to rescue the motility defect, but we now show that these "rescued" null sperm were not hyperactive, displayed flagellar angulation, and remained unable to fertilize eggs in vitro. These deficits uncover a requirement for sAC during spermatogenesis and/or epididymal maturation and reveal limitations inherent in studying sAC function using knockout mice. To circumvent this restriction, we identified a specific sAC inhibitor that allowed temporal control over sAC activity. This inhibitor revealed that capacitation is defined by separable events: induction of protein tyrosine phosphorylation and motility are sAC dependent while acrosomal exocytosis is not dependent on sAC. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|