Hv1 is a voltage-gated proton channel that plays an important role in human sperm physiology.
Intraflagellar alkalinization activates CatSper, the principal Calcium channel in sperm, which is also localized to the principal piece. The combined effects of these two channels can lead to sperm hyperactivation, wherein the sperm cell becomes competent to fertilize the egg.
Miller et al., 2018 introduced a model which explains the cause of the asymmetrical bending observed in hyperactivated sperm. Hv1 is asymmetrically distributed, leading to a higher local pH around the Hv1 channels within the flagellum. This results in greater activation of the nearest CatSper channel, explaining the movement pattern.
Hv1 is not present in mouse sperm.