Voltage-dependent Ca2+ channel subunit expression and immunolocalization in mouse spermatogenic cells and sperm

AbstractThough voltage-dependent Ca2+ channels contribute to the orchestratation of sperm differentiation and function, many questions remain concerning their molecular architecture. This study shows that α1A and α1C Ca2+ channel pore-forming subunits are expressed in spermatogenic cells. In addition, it provides what is to our knowledge the first evidence for the presence of the Ca2+ channel β auxiliary subunits in spermatogenic cells and sperm. Using RT-PCR we demonstrated the expression of all four known genes encoding the β subunits in spermatogenic cells. Specific antibodies detected three of these proteins in spermatogenic cells and sperm. In spermatogenic cells both α1 and β subunits are diffusely distributed throughout the cytoplasm while in sperm they appear to be regionally localized