title: Electrophysiology of single and aggregate Cx43 hemichannels.
abstract: Connexin43 (Cx43) is the most ubiquitous gap junction protein in the human body and is essential for cell-to-cell communication in a variety of organs and organ systems. As a result, Cx43 is responsible for mediating both electrical and chemical signals, passing dissolved solutes and small signaling molecules between cells in a coordinated fashion. Here, we explore the electrophysiological properties of hemichannels formed from Cx43 and Cx43 fused to eGFP (Cx43eGFP) and their interactions in a planar lipid membrane (BLM). Unlike in vivo patch clamp experiments, Cx43 was purified and isolated from other membrane constituents allowing elucidation of individual protein responses to various electrical and chemical stimuli. Using this system, we examined hemichannel electrophysiology and the roles of several well-known gap junction blockers, namely: lanthanum, heptanol, carbenoxalone and lindane. We also observed a critical number of hemichannels required for an accelerated conductance increase, an emergent electrical signature indicative of plaque formation.
authors.affiliation: School of Energy, Environmental, Biological and Medical Engineering, Engineering Research Center, University of Cincinnati, Cincinnati, Ohio, United States of America.
authors.forename: Cole
authors.initials: C
authors.lastname: Brokamp
authors.forename: Jacob
authors.initials: J
authors.lastname: Todd
authors.forename: Carlo
authors.initials: C
authors.lastname: Montemagno
authors.forename: David
authors.initials: D
authors.lastname: Wendell
mesh_terms: D000818:Animals; D000897:Anti-Ulcer Agents / Q000494:pharmacology; D002229:Carbenoxolone / Q000494:pharmacology; D002460:Cell Line; D018031:Connexin 43 / Q000235:genetics / Q000378:metabolism*; D004594:Electrophysiology; D017629:Gap Junctions / Q000187:drug effects; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D019850:Heptanol / Q000494:pharmacology; D001556:Hexachlorocyclohexane / Q000494:pharmacology; D006801:Humans; D007306:Insecticides / Q000494:pharmacology; D008051:Lipid Bilayers / Q000378:metabolism*; D008081:Liposomes / Q000378:metabolism; D008561:Membrane Fusion; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D000897:Anti-Ulcer Agents; D018031:Connexin 43; D007306:Insecticides; D008051:Lipid Bilayers; D008081:Liposomes; D011993:Recombinant Fusion Proteins; D049452:Green Fluorescent Proteins; D001556:Hexachlorocyclohexane; D019850:Heptanol; D002229:Carbenoxolone