Src activation triggers capacitation and acrosome reaction but not motility in human spermatozoa.
Hum Reprod
; 23(12): 2652-62, 2008 Dec.
Article
en En
| MEDLINE
| ID: mdl-18753142
ABSTRACT
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 investigate its role in regulating the processes underlying sperm activation. METHODS ANDRESULTS:
Specific anti-Src antibodies, against different epitopes of the protein, identified a single band of approximately 70 kDa relating to a protein which is mainly localized in the post-acrosomal region of the head, neck and midpiece. By immunoprecipitation and immunofluorescence techniques performed with antibodies against Src phosphorylated at Tyr416, which identifies the active kinase, we showed an increased phosphorylation during sperm capacitation. Blocking Src activity with SU6656 resulted in a significant reduction in the protein tyrosine phosphorylation. Moreover, this inhibitor also blocked the progesterone-induced acrosome reaction and interfered with the calcium response to progesterone evaluated in fura-2-loaded spermatozoa. No effect on sperm motility and hyperactivation resulted from incubation with SU6656.CONCLUSIONS:
We identified a novel Src isoform in human spermatozoa, which appears to be involved in regulating sperm capacitation, calcium fluxes, tyrosine phosphorylation and acrosome reaction.
Texto completo:
1
Bases de datos:
MEDLINE
Asunto principal:
Capacitación Espermática
/
Motilidad Espermática
/
Espermatozoides
/
Familia-src Quinasas
/
Reacción Acrosómica
Límite:
Humans
/
Male
Idioma:
En
Revista:
Hum Reprod
Asunto de la revista:
MEDICINA REPRODUTIVA
Año:
2008
Tipo del documento:
Article
País de afiliación:
Italia