In sea urchin and salmon sperm, pH value regulates whether they remain immotile or swim‎

A study by the Max Planck Institute for Multidisciplinary Sciences and the University of Bonn has shown that pH value is crucial for sperm motility in sea urchins and salmon. An increase in pH activates the enzyme adenylyl cyclase (sAC), which produces the messenger substance cAMP, thereby regulating sperm motility. This mechanism may be widespread among many marine invertebrates and fish. The researchers' findings have now been published in the Proceedings of the National Academy of Sciences.