Non-genomic regulation of mammalian sperm hyperactivation.

Although it has been suggested that the acrosome reaction is induced through non-genomic regulation in a ligand-dependent manner, it is not known whether hyperactivation is similarly regulated. Progesterone and melatonin have been identified as ligands that regulate hyperactivation, the former through non-genomic regulation with phospholipase C and the latter most likely through a reactive oxygen species-mitogen activated protein kinase cascade. Both may be involved in spontaneous regulation of hyperactivation via tyrosine phosphorylation. The concentration of many hormones changes according to environmental conditions and biological rhythms, which will modulate ligand-dependent regulation of hyperactivation.