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http://purl.uniprot.org/citations/1856234http://www.w3.org/1999/02/22-rdf-syntax-ns#typehttp://purl.uniprot.org/core/Journal_Citation
http://purl.uniprot.org/citations/1856234http://www.w3.org/1999/02/22-rdf-syntax-ns#typehttp://purl.uniprot.org/core/Journal_Citation
http://purl.uniprot.org/citations/1856234http://www.w3.org/2000/01/rdf-schema#comment"Expression of lysosomal cysteine proteinases was studied during fetal calf myoblast-myotube differentiation. Activities of cathepsin B and L, but not cathepsin H, increase during bovine myogenic differentiation. In fetal muscle, cathepsin B and L activities are 2-4-fold orders of magnitude lower than in cultured myoblasts. Active-site titrations of cathepsin B with E-64 nevertheless reveal similar concentrations of active cathepsin B in myoblasts and myotubes, but 5-6-fold lower concentrations in fetal muscle. To specify whether concentrations of cathepsin B are related to levels of cathepsin B transcript, a cDNA clone encoding bovine cathepsin B was isolated and liquid hybridizations were performed with 32P-riboprobes complementary to the mRNA. In agreement with active-site titrations, there is no difference in cathepsin B mRNA levels between cultured myoblasts and myotubes, but lower levels of mRNA are found in fetal muscle. Concentrations of active cathepsin B therefore reflect levels of cathepsin B mRNA. Kinetic studies revealed that the catalytic efficiency (kcat/Km) of cathepsin B is 2-3-fold higher in myotubes than in myoblasts. The increase in cathepsin B activity during calf myoblast-myotube differentiation is thus due to modifications of enzymatic properties, and not of enzyme concentrations. The different catalytic efficiency of cathepsin B in myotubes and myoblasts was related neither to modifications of mRNA size, as revealed by Northern blot analysis, nor to a different Mr of the active enzyme, as revealed by affinity labeling with benzyloxycarbonyl-Tyr(-125I)-Ala-CHN2, but to limited differences in cathepsin B isozymes."xsd:string
http://purl.uniprot.org/citations/1856234http://purl.org/dc/terms/identifier"doi:10.1016/s0021-9258(18)92815-2"xsd:string
http://purl.uniprot.org/citations/1856234http://purl.org/dc/terms/identifier"doi:10.1016/s0021-9258(18)92815-2"xsd:string
http://purl.uniprot.org/citations/1856234http://purl.uniprot.org/core/author"Deval C."xsd:string
http://purl.uniprot.org/citations/1856234http://purl.uniprot.org/core/author"Deval C."xsd:string
http://purl.uniprot.org/citations/1856234http://purl.uniprot.org/core/author"Bechet D.M."xsd:string
http://purl.uniprot.org/citations/1856234http://purl.uniprot.org/core/author"Bechet D.M."xsd:string
http://purl.uniprot.org/citations/1856234http://purl.uniprot.org/core/author"Ferrara M.J."xsd:string
http://purl.uniprot.org/citations/1856234http://purl.uniprot.org/core/author"Ferrara M.J."xsd:string
http://purl.uniprot.org/citations/1856234http://purl.uniprot.org/core/author"Mordier S.B."xsd:string
http://purl.uniprot.org/citations/1856234http://purl.uniprot.org/core/author"Mordier S.B."xsd:string
http://purl.uniprot.org/citations/1856234http://purl.uniprot.org/core/author"Obled A."xsd:string
http://purl.uniprot.org/citations/1856234http://purl.uniprot.org/core/author"Obled A."xsd:string
http://purl.uniprot.org/citations/1856234http://purl.uniprot.org/core/author"Roux M.-P."xsd:string
http://purl.uniprot.org/citations/1856234http://purl.uniprot.org/core/author"Roux M.-P."xsd:string
http://purl.uniprot.org/citations/1856234http://purl.uniprot.org/core/date"1991"xsd:gYear
http://purl.uniprot.org/citations/1856234http://purl.uniprot.org/core/date"1991"xsd:gYear
http://purl.uniprot.org/citations/1856234http://purl.uniprot.org/core/name"J. Biol. Chem."xsd:string
http://purl.uniprot.org/citations/1856234http://purl.uniprot.org/core/name"J. Biol. Chem."xsd:string
http://purl.uniprot.org/citations/1856234http://purl.uniprot.org/core/pages"14104-14112"xsd:string
http://purl.uniprot.org/citations/1856234http://purl.uniprot.org/core/pages"14104-14112"xsd:string
http://purl.uniprot.org/citations/1856234http://purl.uniprot.org/core/title"Expression of lysosomal cathepsin B during calf myoblast-myotube differentiation. Characterization of a cDNA encoding bovine cathepsin B."xsd:string
http://purl.uniprot.org/citations/1856234http://purl.uniprot.org/core/title"Expression of lysosomal cathepsin B during calf myoblast-myotube differentiation. Characterization of a cDNA encoding bovine cathepsin B."xsd:string
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