2K7M
Structure of the Connexin40 Carboxyl terminal Domain
Summary for 2K7M
| Entry DOI | 10.2210/pdb2k7m/pdb |
| Descriptor | Gap junction alpha-5 protein (1 entity in total) |
| Functional Keywords | protein, gap junction, cell junction, cell membrane, membrane, transmembrane, membrane protein |
| Biological source | Rattus norvegicus (brown rat,rat,rats) |
| Cellular location | Cell membrane; Multi-pass membrane protein: P28234 |
| Total number of polymer chains | 1 |
| Total formula weight | 11959.02 |
| Authors | Bouvier, D.,Spagnol, G.,Kieken, F.,Vitrac, H.,Kellezi, A.,Forge, V. (deposition date: 2008-08-14, release date: 2009-07-28, Last modification date: 2024-05-22) |
| Primary citation | Bouvier, D.,Spagnol, G.,Chenavas, S.,Kieken, F.,Vitrac, H.,Brownell, S.,Kellezi, A.,Forge, V.,Sorgen, P.L. Characterization of the structure and intermolecular interactions between the connexin40 and connexin43 carboxyl-terminal and cytoplasmic loop domains. J.Biol.Chem., 284:34257-34271, 2009 Cited by PubMed Abstract: Gap junctions are intercellular channels that allow the passage of ions, small molecules, and second messengers that are essential for the coordination of cellular function. They are formed by two hemichannels, each constituted by the oligomerization of six connexins (Cx). Among the 21 different human Cx isoforms, studies have suggested that in the heart, Cx40 and Cx43 can oligomerize to form heteromeric hemichannels. The mechanism of heteromeric channel regulation has not been clearly defined. Tissue ischemia leads to intracellular acidification and closure of Cx43 and Cx40 homomeric channels. However, coexpression of Cx40 and Cx43 in Xenopus oocytes enhances the pH sensitivity of the channel. This phenomenon requires the carboxyl-terminal (CT) part of both connexins. In this study we used different biophysical methods to determine the structure of the Cx40CT and characterize the Cx40CT/Cx43CT interaction. Our results revealed that the Cx40CT is an intrinsically disordered protein similar to the Cx43CT and that the Cx40CT and Cx43CT can interact. Additionally, we have identified an interaction between the Cx40CT and the cytoplasmic loop of Cx40 as well as between the Cx40CT and the cytoplasmic loop of Cx43 (and vice versa). Our studies support the "particle-receptor" model for pH gating of Cx40 and Cx43 gap junction channels and suggest that interactions between cytoplasmic regulatory domains (both homo- and hetero-connexin) could be important for the regulation of heteromeric channels. PubMed: 19808665DOI: 10.1074/jbc.M109.039594 PDB entries with the same primary citation |
| Experimental method | SOLUTION NMR |
Structure validation
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