Conformational changes in surface structures of isolated connexin 26 gap junctions

摘要: Gap junction channels mediate communication between adjacent cells. Using atomic force microscopy (AFM), we have imaged conformational changes of the cytoplasmic and extracellular surfaces native connexin 26 gap plaques. The domains surface, at submolecular resolution, form a hexameric pore protruding from membrane bilayer. Exhibiting an intrinsic flexibility, these domains, comprising C-terminal end, reversibly collapse by increasing forces applied to AFM stylus. connexon surface was after dissection with Upon injection Ca(2+) into buffer solution, channel entrance reduced its diameter 1.5 0.6 nm, change that is fully reversible specific among divalent cations tested. had profound effect on also, inducing formation microdomains. Consequently, plaque height increased nm 18 nm. This suggests calcium ions induce affecting structure both hemichannels intact forming cell-cell contacts.