He adds, "Our laboratory is mainly interested in the basic science of how sperm acquire fertilizing capacity, but one interesting idea here is that this shortcut offers some translational possibilities for calcium ionophore use in IVF. This shortcut may address many of the difficult situations we encounter in IVF, in many species."
In the JBC finalist for "Paper of the Week," Visconti and colleagues including Ana Maria Salicioni address a long-standing question about the presence or not of transmembrane adenylyl cyclases in the highly compartmentalized sperm head and tail and their functional pathways.
Salicioni says, "We show that the rules for producing cAMP in head and tail are different and the targets are different. The main target in the tail is PKA. In the head the target is not clear yet, but it certainly is not PKA. So the cAMP pathways in head and tail are completely different, which is entirely new."
Using biochemical analysis methods in knockout mice, Visconti and colleagues show that while the soluble adenylyl cyclase (sAC) is present in the tail, transmembrane adenylyl cyclases (tmAC) are present in the head sperm compartment. These enzymes are involved in the synthesis of cAMP and, unexpectedly, the signaling pathways using this second messenger are different in the head and tail.
|Contact: Janet Lathrop|
University of Massachusetts at Amherst