Coordinate changes in C protein and myosin expression during skeletal muscle hypertrophy.
In this study, two new C protein isoforms in adult rat skeletal muscle were resolved using sodium dodecyl sulfate-polyacrylamide gel electrophoresis. These isoforms migrated between previously identified fast (Cf) and slow (Cs) C protein isoforms; hence they were named intermediate C proteins (Ci1 and Ci2). Cyanogen bromide peptide mapping and Western blotting showed that the intermediate isoforms were more similar to Cs than Cf. The distribution of specific C protein and myosin heavy chain (MHC) isoforms was highly correlated in several hindlimb muscles, suggesting that the expression of these two thick-filament proteins is coordinated. This notion was tested by determining whether specific C protein and MHC isoforms change in parallel during muscle hypertrophy. Eight weeks after ablation of its synergists, the overloaded plantaris muscle showed significant increases in type IIa MHC and intermediate C protein, with corresponding decreases in type IIb MHC and Cf protein. These results indicate that C protein expression is linked to MHC expression during plantaris muscle hypertrophy.
McCormick
K M
KM
Department of Cell Biology, Duke University Medical School, Durham, North Carolina 27710.
Baldwin
K M
KM
Schachat
F
F
D000818:Animals; D002352:Carrier Proteins / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D006984:Hypertrophy; D015151:Immunoblotting; D007527:Isoenzymes / Q000378:metabolism; D007536:Isomerism; D009132:Muscles / Q000378:metabolism* / Q000473:pathology*; D009218:Myosins / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D014018:Tissue Distribution
D002352:Carrier Proteins; D007527:Isoenzymes; C020723:citrate-binding transport protein; D009218:Myosins