A multiplier peroxiporin signal transduction pathway powers piscine spermatozoa
François Chauvigné, Carla Ducat, Alba Ferré, Tom Hansen, Montserrat Carrascal, Joaquín Abián, Roderick Nigel Finn, Joan Cerdà
Abstract
Significance Spermatozoon swimming performance is critical for fertilization success in fishes, yet the cellular mechanisms that regulate this vital trait are poorly understood. Here, we discovered that a water channel protein, acting as an H 2 O 2 channel (peroxiporin) to detoxify the mitochondria, directly regulates the velocity and progressive motility of both freshwater and marine spermatozoa. The mitochondrial insertion of the peroxiporin is controlled by an increasingly sophisticated hierarchy of intracellular signaling cascades, which evolved into a multiplier stress-activated pathway in modern marine species. These adaptive solutions maximize the postactivated swimming performance of sperm under conditions of high osmotic and oxidative stress. Our findings thus reveal that the pathways regulating the peroxiporin transport in fish spermatozoa provide an advantage for competitive fertilization success.