title: A prokaryotic voltage-gated sodium channel.
abstract: The pore-forming subunits of canonical voltage-gated sodium and calcium channels are encoded by four repeated domains of six-transmembrane (6TM) segments. We expressed and characterized a bacterial ion channel (NaChBac) from Bacillus halodurans that is encoded by one 6TM segment. The sequence, especially in the pore region, is similar to that of voltage-gated calcium channels. The expressed channel was activated by voltage and was blocked by calcium channel blockers. However, the channel was selective for sodium. The identification of NaChBac as a functionally expressed bacterial voltage-sensitive ion-selective channel provides insight into both voltage-dependent activation and divalent cation selectivity.
authors.affiliation: Howard Hughes Medical Institute, Children's Hospital, Harvard Medical School, Enders 1309, 320 Longwood Avenue, Boston, MA 02115, USA.
authors.forename: D
authors.initials: D
authors.lastname: Ren
authors.forename: B
authors.initials: B
authors.lastname: Navarro
authors.forename: H
authors.initials: H
authors.lastname: Xu
authors.forename: L
authors.initials: L
authors.lastname: Yue
authors.forename: Q
authors.initials: Q
authors.lastname: Shi
authors.forename: D E
authors.initials: DE
authors.lastname: Clapham
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D001407:Bacillus / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins; D016466:CHO Cells; D019556:COS Cells; D002118:Calcium / Q000378:metabolism; D002121:Calcium Channel Blockers / Q000494:pharmacology; D015220:Calcium Channels / Q000737:chemistry / Q000378:metabolism; D006224:Cricetinae; D004095:Dihydropyridines / Q000494:pharmacology; D005798:Genes, Bacterial; D015640:Ion Channel Gating; D008564:Membrane Potentials; D008969:Molecular Sequence Data; D008970:Molecular Weight; D016366:Open Reading Frames; D018408:Patch-Clamp Techniques; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins / Q000378:metabolism; D012964:Sodium / Q000378:metabolism*; D015222:Sodium Channels / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D013779:Tetrodotoxin / Q000494:pharmacology; D014162:Transfection
chemical_list: D001426:Bacterial Proteins; D002121:Calcium Channel Blockers; D015220:Calcium Channels; D004095:Dihydropyridines; C443666:NaChBac protein, bacteria; D011994:Recombinant Proteins; D015222:Sodium Channels; D013779:Tetrodotoxin; C038806:1,4-dihydropyridine; D012964:Sodium; D002118:Calcium