The primary structure of troponin T and the interaction with tropomyosin.
1. Eight peptides were separated from the CNBr digest of troponin T from rabbit white skeletal muscle and characterized. 2. By study of the amino acid sequence of the methionine-containing peptides isolated after chymotryptic and tryptic digestion and of the N- and C-terminals of the CNBr peptides, six of the latter were shown to be arranged in the sequence CNB1-CNB2-CNB5-CNB6-CNB8-CNB7. The other two peptides, CNB1' and CNB3, have been shown to be partial digestion products. 3. The CNBr peptides CNB1' and CNB2 contained a common sequence and were the only peptides in CNBr digests of troponin T that formed a complex with tropomyosin as judged by viscometric and electrophoretic studies. 4. It is concluded that tropomyosin interacts with the N-terminal half of the troponin T molecule approximately in the region lying between residues 70 and 160. 5. Electrophoretic evidence indicates that tropomyosin and troponin C interact with troponin T. 6. None of the major CNBr peptides of troponin T isolated formed a complex with troponin C on electrophoresis at pH 8.6.
D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002846:Chromatography, Affinity; D002918:Chymotrypsin; D003488:Cyanogen Bromide; D004591:Electrophoresis, Polyacrylamide Gel; D009124:Muscle Proteins / Q000032:analysis*; D011487:Protein Conformation; D011817:Rabbits; D014335:Tropomyosin; D014336:Troponin / Q000032:analysis*; D014357:Trypsin; D014783:Viscosity
D000596:Amino Acids; D009124:Muscle Proteins; D014335:Tropomyosin; D014336:Troponin; D002918:Chymotrypsin; D014357:Trypsin; D003488:Cyanogen Bromide