No alteration in gene expression of components of the ubiquitin proteasome proteolytic pathway in dystrophin-deficient muscles

• Published in: FEBS letters Vol. 393; no. 2; pp. 292 - 296
• Main Authors: Combaret, Lydie, Taillandier, Daniel, Voisin, Laure, Samuels, Susan E., Boespflug-Tanguy, Odile, Attaix, Didier
• Format: Journal Article
• Language: English
• Published: England Elsevier B.V 16.09.1996; Wiley
• Subjects: 14-kDa E2; 14-kDa ubiquitin conjugating enzyme E2; Adolescent; Animals; Calpain; Calpain - biosynthesis; Cathepsin D - biosynthesis; Cathepsin L; Cathepsins - biosynthesis; Cellular Biology; Child; Cysteine Endopeptidases - biosynthesis; Cysteine Endopeptidases - genetics; DMD; Duchonne muscular dystrophy; Dystrophin - deficiency; Endopeptidases; Female; Fibrosis; Gene Expression; Humans; Life Sciences; Male; Mice; Mice, Inbred mdx; Multienzyme Complexes - biosynthesis; Multienzyme Complexes - genetics; Muscle, Skeletal - metabolism; Muscle, Skeletal - pathology; Muscular Dystrophies - metabolism; Muscular Dystrophies - pathology; Muscular Dystrophies - physiopathology; Muscular dystrophy; Necrosis; Proteasome; Proteasome Endopeptidase Complex; Protein turnover; Reference Values; RNA, Messenger - analysis; Skeletal muscle; Transcription, Genetic; Ubiquitin; Ubiquitins - biosynthesis; Ubiquitins - genetics; Ubiquitin; Calpain; DMD; Skeletal muscle; Protein turnover; Muscular dystrophy; Proteasome; 14-kDa E2
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/0014-5793(96)00910-6

Increased expression of critical components of the ubiquitin-dependent proteolytic pathway occurs in any muscle wasting condition so far studied in rodents where proteolysis rises. We have recently reported similar adaptations in head trauma patients [Mansoor et al. (1996) Proc. Natl. Acad. Sci. USA 93, 2714–2718]. We demonstrate here that the increased muscle protein breakdown seen in mdx mice only correlated with enhanced expression of m-calpain, a Ca 2+-activated proteinase. By contrast, no change in mRNA levels for components of the ubiquitin-proteasome proteolytic process was seen in muscles from both mdx mice and Duchenne muscular dystrophy patients. Thus, gene expression of components of this pathway is not regulated in the chronic wasting that characterizes muscular dystrophy.