The HVCN1 gene codes for a voltage-gated proton channel

Voltage-gated proton channel

Voltage-gated proton channels are ion channels that have the unique property of opening with depolarization, but in a strongly pH-sensitive manner. The result is that these channels open only when the electrochemical gradient is outward, such that their opening will only allow protons to leave cells...

 that has been shown to allow proton transport into phagosome

Phagosome

In cell biology, a phagosome is a vacuole formed around a particle absorbed by phagocytosis. The vacuole is formed by the fusion of the cell membrane around the particle. A phagosome is a cellular compartment in which pathogenic microorganisms can be killed and digested...

s and out of many types of cells including spermatozoa, electrically excitable

Action potential

In physiology, an action potential is a short-lasting event in which the electrical membrane potential of a cell rapidly rises and falls, following a consistent trajectory. Action potentials occur in several types of animal cells, called excitable cells, which include neurons, muscle cells, and...

 cells and respiratory epithelial

Respiratory epithelium

Respiratory epithelium is a type of epithelium found lining the respiratory tract, where it serves to moisten and protect the airways. It also functions as a barrier to potential pathogens and foreign particles, preventing infection and tissue injury by action of the mucociliary escalator.-...

 cells. The proton-conducting HVCN1 channel has only transmembrane domains corresponding to the S1-S4 voltage sensing domains (VSD) of voltage-gated potassium channel

Voltage-gated potassium channel

Voltage-gated potassium channels are transmembrane channels specific for potassium and sensitive to voltage changes in the cell's membrane potential. During action potentials, they play a crucial role in returning the depolarized cell to a resting state....

s and voltage-gated sodium channels. Molecular simulation is consistent with a water-filled pore that can function as a "water wire

Grotthuss mechanism

The Grotthuss mechanism is the mechanism by which an 'excess' proton or protonic defect diffuses through the hydrogen bond network of water molecules or other hydrogen-bonded liquids through the formation or cleavage of covalent bonds....

" for allowing hydrogen bonded H⁺ to cross the membrane. The HVCN1 protein has been shown to exist as a dimer with two functioning pores. Like other VSD channels, HVCN1 channels conduct ions about 1000-fold slower than channels formed by tetrameric S5-S6 central pores.