1. The functional significance of the last 5 residues of the C-terminus of cardiac troponin I
- Author
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Gilda, Jennifer E, Xu, Qian, Martinez, Margaret E, Nguyen, Susan T, Chase, P Bryant, and Gomes, Aldrin V
- Subjects
Myocardial Stunning ,Adenosine Triphosphatases ,Microscopy ,Biochemistry & Molecular Biology ,Myocardium ,Troponin I ,In vitro motility assay ,Mammalian two-hybrid ,Heart ,Cardiovascular ,Fluorescence ,Unloaded filament sliding ,Actin Cytoskeleton ,Heart Disease ,Protein Domains ,Two-Hybrid System Techniques ,Mutation ,Genetics ,Humans ,Calcium ,Biochemistry and Cell Biology ,Troponin C ,Gene Deletion - Abstract
The C-terminal region of cardiac troponin I (cTnI) is known to be important in cardiac function, as removal of the last 17C-terminal residues of human cTnI has been associated with myocardial stunning. To investigate the C-terminal region of cTnI, three C-terminal deletion mutations in human cTnI were generated: Δ1 (deletion of residue 210), Δ3 (deletion of residues 208-210), and Δ5 (deletion of residues 206-210). Mammalian two-hybrid studies showed that the interactions between cTnI mutants and cardiac troponin C (cTnC) or cardiac troponin T (cTnT) were impaired in Δ3 and Δ5 mutants when compared to wild-type cTnI. Troponin complexes containing 2-[4'-(iodoacetamido) anilino] naphthalene-6-sulfonic acid (IAANS) labeled cTnC showed that the troponin complex containing cTnI Δ5 had a small increase in Ca(2+) affinity (P 
- Published
- 2016