title: The interaction of the bisphosphorylated N-terminal arm of cardiac troponin I-A 31P-NMR study.
abstract: Cardiac troponin I, the inhibitory subunit of the heterotrimeric cardiac troponin (cTn) complex is phosphorylated by protein kinase A at two serine residues located in its heart-specific N-terminal extension. This flexible arm interacts at different sites within cTn dependent on its phosphorylation degree. Bisphosphorylation is known to induce conformational changes within cTnI which finally lead to a reduction of the calcium affinity of cTnC. However, as we show here, the bisphosphorylated cTnI arm does not interact with cTnC, but with cTnT and/or cTnI.
authors.affiliation: Physiologische Chemie, Abt. Biochemie Supramolekularer Systeme, Medizinische Fakultät, Ruhr-Universität Bochum, MA 2/39, 44780, Bochum, Germany.
authors.forename: Anja
authors.initials: A
authors.lastname: Schmidtmann
authors.forename: Karin
authors.initials: K
authors.lastname: Lohmann
authors.forename: Kornelia
authors.initials: K
authors.lastname: Jaquet
mesh_terms: D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D009206:Myocardium / Q000378:metabolism*; D010759:Phosphorus Isotopes; D010766:Phosphorylation; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D019209:Troponin C / Q000378:metabolism; D019210:Troponin I / Q000737:chemistry / Q000378:metabolism*; D020107:Troponin T / Q000378:metabolism
chemical_list: D010759:Phosphorus Isotopes; D019209:Troponin C; D019210:Troponin I; D020107:Troponin T