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The structure of the carboxyl-terminal domain of the human voltage-gated proton channel Hv1The structure of the carboxyl-terminal domain of the human voltage-gated proton channel Hv1
Structural highlights
FunctionHVCN1_HUMAN Mediates the voltage-dependent proton permeability of excitable membranes. Forms a proton-selective channel through which protons may pass in accordance with their electrochemical gradient. Proton efflux, accompanied by membrane depolarization, facilitates acute production of reactive oxygen species in phagocytosis.[1] [2] [3] Publication Abstract from PubMedThe voltage-gated proton channel Hv1 has a voltage sensor domain but lacks a pore domain. Although the C-terminal domain of Hv1 is known to be responsible for dimeric architecture of the channel, its role and structure are not known. We report that the full-length Hv1 is mainly localized in intracellular compartment membranes rather than the plasma membrane. Truncation of either the N or C terminus alone or both together revealed that the N-terminal deletion did not alter localization, but deletion of the C terminus either alone or together with the N terminus resulted in expression throughout the cell. These results indicate that the C terminus is essential for Hv1 localization but not the N terminus. In the 2.0 A structure of the C-terminal domain, the two monomers form a dimer via a parallel alpha-helical coiled-coil, in which one chloride ion binds with the Neta atom of Arg(264). A pH-dependent structural change of the protein has been observed, but it remains a dimer irrespective of pH value. The role and structure of the carboxyl-terminal domain of the human voltage-gated proton channel Hv1.,Li SJ, Zhao Q, Zhou Q, Unno H, Zhai Y, Sun F J Biol Chem. 2010 Apr 16;285(16):12047-54. Epub 2010 Feb 10. PMID:20147290[4] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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