Location of modulatory beta subunits in BK potassium channels.
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ABSTRACT:
SUBMITTER: Liu G
PROVIDER: S-EPMC2860586 | biostudies-literature | 2010 May
REPOSITORIES: biostudies-literature
Publications
Location of modulatory beta subunits in BK potassium channels.
Liu Guoxia G Niu Xiaowei X Wu Roland S RS Chudasama Neelesh N Yao Yongneng Y Jin Xin X Weinberg Richard R Zakharov Sergey I SI Motoike Howard H Marx Steven O SO Karlin Arthur A
The Journal of general physiology 20100412 5
Large-conductance voltage- and calcium-activated potassium (BK) channels contain four pore-forming alpha subunits and four modulatory beta subunits. From the extents of disulfide cross-linking in channels on the cell surface between cysteine (Cys) substituted for residues in the first turns in the membrane of the S0 transmembrane (TM) helix, unique to BK alpha, and of the voltage-sensing domain TM helices S1-S4, we infer that S0 is next to S3 and S4, but not to S1 and S2. Furthermore, of the two ...[more]
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