Replacement of three troponin components with cardiac troponin components within single glycerinated skeletal muscle fibers.
The tension of single glycerinated rabbit skeletal muscle fiber was desensitized to a Ca(2+)-concentration after treatment with an excessive amount of bovine cardiac troponin T and reached a level of about 70% of the maximum tension of the untreated fiber. A SDS-gel electrophoretic examination indicated that troponin C.I.T complex in the fiber was replaced with the added cardiac troponin T. The Ca(2+)-sensitivity of the tension of the troponin T-treated fiber was then recovered by the addition of bovine cardiac troponins I and C. The rabbit skeletal muscle fiber thus hybridized with bovine cardiac troponin C.I.T showed the same cooperativity of Ca(2+)-activation as the cardiac muscle.
Hatakenaka
M
M
Department of Pharmacology, Faculty of Medicine, Kyushu University, Fukuoka, Japan.
Ohtsuki
I
I
D000818:Animals; D002118:Calcium / Q000494:pharmacology*; D002417:Cattle; D003285:Contractile Proteins / Q000302:isolation & purification / Q000502:physiology; D004591:Electrophoresis, Polyacrylamide Gel; D066298:In Vitro Techniques; D009119:Muscle Contraction / Q000187:drug effects*; D009132:Muscles / Q000187:drug effects / Q000502:physiology*; D011817:Rabbits; D014336:Troponin / Q000494:pharmacology* / Q000502:physiology*; D020107:Troponin T
D003285:Contractile Proteins; D014336:Troponin; D020107:Troponin T; D002118:Calcium