Identification of SRC as a key PKA-stimulated tyrosine kinase involved in the capacitation-associated hyperactivation of murine spermatozoa.

Src activation triggers capacitation and acrosome reaction but not motility in human spermatozoa.

BACKGROUND Protein tyrosine phosphorylation is one of the main processes associated with sperm activation. Although this process and its targets have been well characterized, only few tyrosine kinases have been identified so far and their roles in spermatozoa are still largely unknown. In this study, we report the presence and localization of Src kinase in ejaculated human spermatozoa and inves...

P-56: Effect of Cissampelos Capensis Rhizome Extract on Human Sperm Capacitation and Acrosome Reaction

s:2086:"Background: Cissampelos capensis, is commonly known by the Afrikaans name "dawidjies" and is the most important and best known medicinal plant of the family Menispermaceae used by the Khoisan and other rural people in the western regions of South Africa. Among numerous other ailments, it is taken to treat male fertility problems. The aim of this study was to investigate the effects of C...

Effects of Ca and HCO3 on Capacitation, Hyperactivation and Protein Tyrosine Phosphorylation in Guinea Pig Spermatozoa

In our previous report, we demonstrated that the tyrosine phosphorylation of sperm proteins (TPSP) of guinea pig was associated with capacitation and hyperactivation (CAHA), and Ca and HCO3 were required for the initiation of CAHA and increasing the TPSP. The aim of this study was to further investigate the mechanism underlying the above events. The results showed that addition of cAMP agonists...

Involvement of intracellular calcium and src tyrosine-kinase in capacitation of cryopreserved bovine spermatozoa

Evidence for the involvement of proline-rich tyrosine kinase 2 in tyrosine phosphorylation downstream of protein kinase A activation during human sperm capacitation.

Sperm capacitation involves an increase in intracellular Ca(2+) concentration as well as in protein kinase A (PKA)-dependent protein tyrosine (Tyr) phosphorylation. Interestingly, in humans, a decrease in extracellular Ca(2+) concentration ([Ca(2+)]e) during capacitation induces an increase in Tyr phosphorylation indicating the complexity of Ca(2+) signaling during this process. In view of this...