Using limited proteolysis by chymotrypsin or papain, we examined the effects of phosphorylation on the conformation of skeletal muscle myosin. In the absence of MgCl2, phosphorylation of the 19,000 dalton light chain (LC2) inhibited digestion of LC2 by chymotrypsin or papain. Phosphorylation also suppressed chymotryptic conversion of the heavy chain to subfragment 1 and increased its conversion to heavy meromyosin. These results indicate that phosphorylation alters the conformation of the N-terminal segment of LC2 and suggest that it also affects the heavy chain. In the presence of MgCl2, phosphorylation inhibited the chymotryptic digestion of LC2 but an effect on digestion of the heavy chain was not apparent. Thus, phosphorylation of LC2 alters LC2 conformation under physiological conditions.
|Original language||English (US)|
|Number of pages||6|
|Journal||Biochemical and Biophysical Research Communications|
|State||Published - Mar 13 1980|
ASJC Scopus subject areas
- Molecular Biology
- Cell Biology