Structure and selectivity in bestrophin ion channels.
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ABSTRACT:
SUBMITTER: Yang T
PROVIDER: S-EPMC4341822 | biostudies-literature | 2014 Oct
REPOSITORIES: biostudies-literature
Publications
Structure and selectivity in bestrophin ion channels.
Yang Tingting T Liu Qun Q Kloss Brian B Bruni Renato R Kalathur Ravi C RC Kalathur Ravi C RC Guo Youzhong Y Kloppmann Edda E Rost Burkhard B Colecraft Henry M HM Hendrickson Wayne A WA
Science (New York, N.Y.) 20140925 6207
Human bestrophin-1 (hBest1) is a calcium-activated chloride channel from the retinal pigment epithelium, where mutations are associated with vitelliform macular degeneration, or Best disease. We describe the structure of a bacterial homolog (KpBest) of hBest1 and functional characterizations of both channels. KpBest is a pentamer that forms a five-helix transmembrane pore, closed by three rings of conserved hydrophobic residues, and has a cytoplasmic cavern with a restricted exit. From electroph ...[more]
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