Phosphorylation of troponin T by Ca-phospholipid-dependent protein kinase.
Phosphorylation of skeletal and cardiac troponin T by Ca-phospholipid-dependent protein kinase/protein kinase C/was investigated. Under conditions used, the rate of troponin T phosphorylation was only 3-4 times lower than that of histone H-1, and after long term incubation the enzyme incorporated about 1 mol of phosphate per mol of skeletal and cardiac troponin T. The sites phosphorylated by protein kinase C are mainly located in the C-terminal part/residues 159-259/of skeletal troponin T. The less effectively phosphorylated sites are located in between residues 42-158 of troponin T. Reverse phase HPLC revealed four groups of tryptic phosphopeptides of troponin T. The phosphopeptides weakly adsorbed on a RP-18 column were identified as a mixture of two peptides/GKKQTAR and QTAR/both containing Thr-171 of troponin T phosphorylated by protein kinase C.
Department of Biochemistry, School of Biology, Moscow State University, USSR.
V V
VV
Risnik
A V
AV
Vorotnikov
N B
NB
Gusev
D000818:Animals; D001665:Binding Sites; D066298:In Vitro Techniques; D009132:Muscles / Q000378:metabolism; D009206:Myocardium / Q000378:metabolism; D010446:Peptide Fragments / Q000378:metabolism; D010766:Phosphorylation; D011493:Protein Kinase C / Q000378:metabolism*; D051381:Rats; D014336:Troponin / Q000378:metabolism*; D020107:Troponin T
D010446:Peptide Fragments; D014336:Troponin; D020107:Troponin T; D011493:Protein Kinase C