Is the S4 helix of Hv Short?

In this post, I will elaborate upon a statement I made in last week’s post. There, I discussed how important a proper alignment of the S4 helices in voltage sensor domains (VSDs) is for building accurate homology-based structural models of these domains. ¬†When discussing the potential alignments I stated that “since the different conformations of … Continue reading

The Problem of Aligning S4

Recently, a number of papers have come out that have used sequence homology to generate structural models of human Hv1 (Musset et al,. 2010; Ramsey et al., 2010; Wood et al., 2012). These models have then been used for docking and molecular-dynamics simulations to try to extract some mechanistic insight into the channel function. In … Continue reading

The Mechanism of Voltage Gating in Potassium Channels? – Part 2 Activation

OK, time for part 2. If you missed part 1 of this two post series check it out here. Just to recap, I am discussing the recent Science paper (April 13th issue) from the D.E. Shaw Research group, entitled “The Mechanism of Voltage Gating in Potassium Channels.” In this paper, Jensen et al. use their … Continue reading

Hv Physiology: Human Male Fertility

The human voltage-gated proton channel Hv1 plays an important physiological role in male fertility in humans. Specifically it is integral for regulation of the internal pH of the sperm cell. The pH of the sperm cytoplasm is a major regulator of sperm cell motility, capacitation, hyperctivation and the acrosome reaction. Each of these processes are … Continue reading