Reduced protein degradation rates and low expression of proteolytic systems support skeletal muscle hypertrophy in transgenic mice overexpressing the c-ski oncogene.
We have investigated the protein turnover modulations involved in the hypertrophic muscle phenotype of c-ski overexpressing transgenic mice. In these animals, the body weight is increased and all the muscles examined show a definite hypertrophy. The protein degradation rate is significantly reduced in the fast twitch muscles of c-ski transgenic animals with respect to controls; in contrast, there are no detectable differences in the synthesis rates. The down-regulation of protein breakdown is paralleled by decreased expression of genes belonging to the lysosomal as well as to the ATP-ubiquitin-dependent proteolytic pathways.
Costelli
Paola
P
Dipartimento di Medicina ed Oncologia Sperimentale, Università di Torino, Torino, Italy.
Carbó
Neus
N
Busquets
Sílvia
S
López-Soriano
Francisco J
FJ
Baccino
Francesco M
FM
Argilés
Josep M
JM
D000818:Animals; D001835:Body Weight; D004268:DNA-Binding Proteins / Q000235:genetics*; D006984:Hypertrophy; D051379:Mice; D008822:Mice, Transgenic; D008954:Models, Biological; D009124:Muscle Proteins / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000473:pathology*; D009929:Organ Size; D010447:Peptide Hydrolases; D011518:Proto-Oncogene Proteins / Q000235:genetics*
D004268:DNA-Binding Proteins; D009124:Muscle Proteins; D011518:Proto-Oncogene Proteins; C512653:Ski protein, mouse; D010447:Peptide Hydrolases