Project description:Duchenne muscular dystrophy (DMD) is an X-linked recessive disease caused by deleterious mutations in the DMD gene, rendering non-functional forms or complete absence of the protein dystrophin. Eccentric contraction-induced force loss is the most robust and reproducible phenotype of dystrophin-deficient skeletal muscle, yet the molecular mechanisms underlying force loss remain obscure. To this end, we utilized the mdx mouse model of DMD, which displays extreme sensitivity to eccentric contractions. An existing mouse line from our lab that overexpresses cytoplasmic gamma-actin specifically in skeletal muscle (mdx/Actg1-TG) was shown to significantly protect mdx muscle against contraction-induced force loss. To understand the mechanism behind this protection, we performed iTRAQ proteomics on mdx/Actg1-TG tibialis anterior (TA) muscle versus non-transgenic littermate controls to identify differentially-expressed proteins that may afford protection upon gamma-actin overexpression.
Project description:Despite over 3,000 articles published on dystrophin in the last 15 years, the reasons underlying the progression of the human disease, differential muscle involvement, and disparate phenotypes in different species are not understood. The present experiment employed a screen of 12,488 mRNAs in 16-wk-old mouse mdx muscle at a time when the skeletal muscle is avoiding severe dystrophic pathophysiology, despite the absence of a functional dystrophin protein. A number of transcripts whose levels differed between the mdx and human Duchenne muscular dystrophy were noted. A fourfold decrease in myostatin mRNA in the mdx muscle was noted. Differential upregulation of actin-related protein 2/3 (subunit 4), beta-thymosin, calponin, mast cell chymase, and guanidinoacetate methyltransferase mRNA in the more benign mdx was also observed. Transcripts for oxidative and glycolytic enzymes in mdx muscle were not downregulated. These discrepancies could provide candidates for salvage pathways that maintain skeletal muscle integrity in the absence of a functional dystrophin protein in mdx skeletal muscle. Keywords: other
Project description:Determination of gene expression changes in extraocular and hindlimb (gastrocnemius/soleus) of mdx (dystrophin-deficient) mice at postnatal day 56. 5 independent replicates/muscle group/strain. Keywords: parallel sample
Project description:In this study, Pax7-Cre mediated inactivation of Sirt6 in mdx mice resulted in profound improvement of the mdx phenotype at the functional level. To study the underlying molecular mechanisms we performed RNA-seq of muscles from control, mdx and Sirt6mKO/mdx mice.
Project description:In this study, Pax7-Cre mediated inactivation of Sirt6 in mdx mice resulted in profound improvement of the mdx phenotype at the functional level. To study the underlying molecular mechanisms we performed RNA-seq of MuSCs from control, mdx and Sirt6mKO/mdx mice.