title: Stabilization of calpain large subunits by overexpression of truncated calpain small subunit in L8 myoblasts.
abstract: The objectives were to investigate the function of the small subunit in the calpain system by expression of the autolytic form of this subunit in L8 myoblasts. Rat post-autolysis small subunit (21 kDa) cDNA expression plasmid was transfected into L8 myoblasts and selected by G418 containing medium. The concentrations of cytosolic micro-calpain in transfected cells, SS2 and SS3, were found to be 15.7 and 17.3% higher than that in L8Neo control cells, and the concentrations of cytosolic m-calpain in SS2 and SS3 cells were 23.3 and 16.6% higher than that in control cells (L8Neo). The half-life of micro-calpain in SS3 cells (36.5 h) was longer than that in L8Neo cells (32.4 h), while the half-life of m-calpain in SS3 cells (40.1 h) was longer than that in L8Neo cell (37.5 h). These results indicated that the expression of truncated small subunit increased the stability of micro- and m-calpain large subunits in cytosol.
authors.affiliation: Department of Animal Science, Tunghai University, Taichung 407, Taiwan, ROC.
authors.forename: T C
authors.initials: TC
authors.lastname: Chung
authors.forename: Y C
authors.initials: YC
authors.lastname: Liang
authors.forename: J Y
authors.initials: JY
authors.lastname: Yeh
authors.forename: B R
authors.initials: BR
authors.lastname: Ou
mesh_terms: D000818:Animals; D002154:Calpain / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D003600:Cytosol / Q000378:metabolism; D004795:Enzyme Stability; D015870:Gene Expression; D032446:Myoblasts / Q000378:metabolism*; D021122:Protein Subunits / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017384:Sequence Deletion / Q000235:genetics; D014162:Transfection
chemical_list: D021122:Protein Subunits; D002154:Calpain