Transmembrane adenylyl cyclase regulates amphibian sperm motility through protein kinase A activation.
Sperm motility is essential for achieving fertilization. In animals with external fertilization as amphibians, spermatozoa are stored in a quiescent state in the testis. Spermiation to hypotonic fertilization media triggers activation of sperm motility. Bufo arenarum sperm are immotile in artificial seminal plasma (ASP) but acquire in situ flagellar beating upon dilution. In addition to the effect of low osmolarity on sperm motility activation, we report that diffusible factors of the egg jelly coat (EW) regulate motility patterns, switching from in situ to progressive movement. The signal transduction pathway involved in amphibian sperm motility activation is mostly unknown. In the present study, we show a correlation between motility activation triggered by low osmotic pressure and activation of protein kinase A (PKA). Moreover, this is the first study to present strong evidences that point toward a role of a transmembrane adenyl-cyclase (tmAC) in the regulation of amphibian sperm motility through PKA activation.
Institute of Molecular and Cell Biology of Rosario (CONICET-UNR) and Área Biología, Facultad de Ciencias Biológicas y Farmacéuticas, UNR, Argentina.
Emma D
ED
O'Brien
Darío
D
Krapf
Marcelo O
MO
Cabada
Pablo E
PE
Visconti
Silvia E
SE
Arranz
D000067956:Adenylyl Cyclase Inhibitors; D000262:Adenylyl Cyclases / Q000378:metabolism*; D000818:Animals; D002022:Bufo arenarum / Q000502:physiology*; D002462:Cell Membrane / Q000201:enzymology; D000242:Cyclic AMP / Q000378:metabolism; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism*; D004789:Enzyme Activation; D007038:Hypotonic Solutions / Q000494:pharmacology; D008297:Male; D010766:Phosphorylation; D013081:Sperm Motility; D013094:Spermatozoa / Q000187:drug effects / Q000201:enzymology / Q000502:physiology*
D000067956:Adenylyl Cyclase Inhibitors; D007038:Hypotonic Solutions; D000242:Cyclic AMP; D017868:Cyclic AMP-Dependent Protein Kinases; D000262:Adenylyl Cyclases