title: Adenosine-triphosphate-sensitive K+ channel (Kir6.1): a novel phosphospecific interaction partner of connexin 43 (Cx43).
abstract: Connexin 43 (Cx43) is a phosphoprotein expressed in a wide variety of cells. Cx43 and adenosine-triphosphate-sensitive K(+)channels [K(+)(ATP)] are part of same signaling pathway that regulates cell survival during stress and ischemia preconditioning. Molecular mechanism for their coordinated role in ischemia/hypoxia preconditioning is not well known. Using pull down, co-immunoprecipitation assays and co-localization studies we provide evidence, for the first time that Kir6.1, a K(+)(ATP) channel protein component, can interact with Cx43. Further we show that the interaction was phospho-specific such that Cx43 phosphorylated at serine 262 (S262) interacted with Kir6.1 in preference to the unphosphorylated form of Cx43. Introduction of phospho-deficient mutation at serine 262 (S262A) in Cx43 completely abolished the interaction. Our data provide an interesting lead about a possible partnership between Cx43 and Kir6.1, which will help in better understanding their role in ischemia/hypoxia preconditioning.
authors.affiliation: Department of Biotechnology, University of Kashmir, India.
authors.forename: Ajaz
authors.initials: A
authors.lastname: Ahmad Waza
authors.forename: Khurshid
authors.initials: K
authors.lastname: Andrabi
authors.forename: Mahboob
authors.initials: M
authors.lastname: Ul Hussain
mesh_terms: D000255:Adenosine Triphosphate / Q000633:toxicity*; D000818:Animals; D018031:Connexin 43 / Q000235:genetics / Q000378:metabolism*; D000860:Hypoxia / Q000235:genetics / Q000378:metabolism*; D007511:Ischemia / Q000235:genetics / Q000378:metabolism*; D019194:Ischemic Preconditioning / Q000379:methods*; D054086:KATP Channels / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D016297:Mutagenesis, Site-Directed; D041681:NIH 3T3 Cells; D010766:Phosphorylation / Q000235:genetics
chemical_list: D018031:Connexin 43; C543076:GJA1 protein, mouse; D054086:KATP Channels; C092520:uK-ATP-1 potassium channel; D000255:Adenosine Triphosphate