title: Regulation of the calpain and ubiquitin-proteasome systems in a canine model of muscular dystrophy.
abstract: BACKGROUND
  Previous studies have tested the hypothesis that calpain and/or proteasome inhibition is beneficial in Duchenne muscular dystrophy, based largely on evidence that calpain and proteasome activities are enhanced in the mdx mouse.
  
  
  METHODS
  mRNA expression of ubiquitin-proteasome and calpain system components were determined using real-time polymerase chain reaction in skeletal muscle and heart in the golden retriever muscular dystrophy model. Similarly, calpain 1 and 2 and proteasome activities were determined using fluorometric activity assays.
  
  
  RESULTS
  We found that less than half of the muscles tested had increases in proteasome activity, and only half had increased calpain activity. In addition, transcriptional regulation of the ubiquitin-proteasome system was most pronounced in the heart, where numerous components were significantly decreased.
  
  
  CONCLUSIONS
  This study illustrates the diversity of expression and activities of the ubiquitin-proteasome and calpain systems, which may lead to unexpected consequences in response to pharmacological inhibition.
authors.affiliation: Department of Pathology and Laboratory Medicine, University of North Carolina, Chapel Hill, North Carolina, USA.
authors.forename: Kristine M
authors.initials: KM
authors.lastname: Wadosky
authors.forename: Luge
authors.initials: L
authors.lastname: Li
authors.forename: Jessica E
authors.initials: JE
authors.lastname: Rodríguez
authors.forename: Jin-Na
authors.initials: JN
authors.lastname: Min
authors.forename: Dan
authors.initials: D
authors.lastname: Bogan
authors.forename: Jason
authors.initials: J
authors.lastname: Gonzalez
authors.forename: Cam
authors.initials: C
authors.lastname: Patterson
authors.forename: Joe N
authors.initials: JN
authors.lastname: Kornegay
authors.forename: Monte
authors.initials: M
authors.lastname: Willis
mesh_terms: D000818:Animals; D002154:Calpain / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D004195:Disease Models, Animal; D004285:Dogs; D005786:Gene Expression Regulation / Q000502:physiology; D018482:Muscle, Skeletal / Q000378:metabolism*; D009137:Muscular Dystrophy, Animal / Q000378:metabolism / Q000473:pathology*; D009206:Myocardium / Q000378:metabolism; D046988:Proteasome Endopeptidase Complex / Q000235:genetics / Q000378:metabolism*; D025801:Ubiquitin / Q000235:genetics / Q000378:metabolism*; D043743:Ubiquitin-Protein Ligase Complexes / Q000378:metabolism
chemical_list: D025801:Ubiquitin; D043743:Ubiquitin-Protein Ligase Complexes; D002154:Calpain; D046988:Proteasome Endopeptidase Complex