Polymer Partitioning and Ion Selectivity Suggest Asymmetrical Shape for the Membrane Pore Formed by Epsilon Toxin
نویسندگان
چکیده
منابع مشابه
Asymmetrical contributions of subunit pore regions to ion selectivity in an inward rectifier K+ channel.
We have investigated aspects of ion selectivity in K+ channels by functional expression of wild-type and mutant heteromultimeric G protein-coupled inward-rectifier K+ (GIRK) channels in Xenopus oocytes. Within the K+ channel pore (P) region signature sequence, a large number of point mutations in GIRK1 and GIRK4 subunits have been made at a key tyrosine residue--the "signature" tyrosine of the ...
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متن کاملPore-forming epsilon toxin causes membrane permeabilization and rapid ATP depletion-mediated cell death in renal collecting duct cells.
Clostridium perfringens epsilon toxin (ET) is a potent pore-forming cytotoxin causing fatal enterotoxemia in livestock. ET accumulates in brain and kidney, particularly in the renal distal-collecting ducts. ET binds and oligomerizes in detergent-resistant membranes (DRMs) microdomains and causes cell death. However, the causal linkage between membrane permeabilization and cell death is not clea...
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ژورنال
عنوان ژورنال: Biophysical Journal
سال: 2010
ISSN: 0006-3495
DOI: 10.1016/j.bpj.2010.05.014