“…The characterization of NOX5 and its putative role in ROS production are important to understand the relationship between the redox state and the biological function of sperm. A growing body of evidence indicates a role for ROS in a variety of sperm functions, including capacitation (Leclerc et al 1997), tyrosine phosphorylation (Aitken et al 1996, Leclerc et al 1997, Baumber et al 2003, O'Flaherty et al 2006, chromatin condensation (Godeas et al 1997), regulation of intracellular pH ) and acrosomal exocytosis (Rivlin et al 2004). Several studies including ours (Aitken & Clarkson 1987, Aitken et al 1995, Tselkas et al 2000, O'Flaherty et al 2003, Sabeur & Ball 2006 have shown that mammalian spermatozoa are capable of generating ROS but the biochemical mechanisms by which ROS are generated in mammalian spermatozoa are not fully understood.…”