The function of SLC9C1 (solute carrier family 9 member C1, ENSG00000172139) is as follows. Sperm-specific solute carrier involved in intracellular pH regulation of spermatozoa. Required for sperm motility and fertility. Involved in sperm cell hyperactivation, a step needed for sperm motility which is essential late in the preparation of sperm for fertilization. Required for the expression and bicarbonate regulation of the soluble adenylyl cyclase (sAC) (By similarity). .