Regenerative myogenesis is the formation of muscle progenitors during the repair of adult skeletal muscle following tissue trauma. In this application, we outline a research program to molecularly define the genetic mechanisms through which Pax7 enforces lineage commitment during regenerative myogenesis. To fully define the Pax7 regulome in primary myoblasts, Pax7 bound to fragmented chromatin will be immunoprecipitated and the DNA isolated and subjected to a subtractive PCR-based procedure to selectively amplify Pax7 binding sites. Direct targets will be identified by a comparative analysis between our existing microarray data, and regulatory regions that recruit Pax7. The function of a select set of prioritized candidate target genes will be investigated using molecular and genetic approaches. Real-time PCR will be used to characterize cell-type and differentiation patterns of expression. Knock down experiments will be performed with RNAi, and full-length cDNAs over-expressed in myoblasts. Lastly, the binding of Pax7 alternative splice forms to candidate promoters will be evaluated. To investigate the hypothesis that Pax7 recruits co-factors to facilitate appropriate regulation of target genes, the ability of Pax7 to direct acetyl-transferase activity will be investigated, and chromatin immunoprecipitation assays will be used to characterize the histone modifications over Pax7 target promoters. A genome wide assessment of histone modifications using microarrays will be conducted. To elucidate Pax7 function, we will isolate and identify protein components of the Pax7 transcriptional complex by mass spectroscopy. These experimental approaches will facilitate a molecular understanding of Pax7 function and the genomic definition of the chromatin domains established by Pax7. Understanding the molecular mechanism regulating gene function during muscle regeneration will provide insights that will potentially lead to new modalities of therapeutic intervention for the treatment of muscle degenerative disease. ? ?

Agency
National Institute of Health (NIH)
Institute
National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS)
Type
Research Project (R01)
Project #
5R01AR044031-11
Application #
7230551
Study Section
Special Emphasis Panel (ZRG1-DEV-1 (01))
Program Officer
Boyce, Amanda T
Project Start
1996-07-15
Project End
2010-04-30
Budget Start
2007-05-01
Budget End
2008-04-30
Support Year
11
Fiscal Year
2007
Total Cost
$208,600
Indirect Cost
Name
Ottawa Hospital Research Institute
Department
Type
DUNS #
201768095
City
Ottawa
State
ON
Country
Canada
Zip Code
K1 4-E9
Soleimani, Vahab D; Nguyen, Duy; Ramachandran, Parameswaran et al. (2018) Cis-regulatory determinants of MyoD function. Nucleic Acids Res 46:7221-7235
Feige, Peter; Brun, Caroline E; Ritso, Morten et al. (2018) Orienting Muscle Stem Cells for Regeneration in Homeostasis, Aging, and Disease. Cell Stem Cell 23:653-664
Brun, Caroline E; Wang, Yu Xin; Rudnicki, Michael A (2018) Single EDL Myofiber Isolation for Analyses of Quiescent and Activated Muscle Stem Cells. Methods Mol Biol 1686:149-159
Bar-Nur, Ori; Gerli, Mattia F M; Di Stefano, Bruno et al. (2018) Direct Reprogramming of Mouse Fibroblasts into Functional Skeletal Muscle Progenitors. Stem Cell Reports 10:1505-1521
Chang, Natasha C; Sincennes, Marie-Claude; Chevalier, Fabien P et al. (2018) The Dystrophin Glycoprotein Complex Regulates the Epigenetic Activation of Muscle Stem Cell Commitment. Cell Stem Cell 22:755-768.e6
Hernández-Hernández, J Manuel; García-González, Estela G; Brun, Caroline E et al. (2017) The myogenic regulatory factors, determinants of muscle development, cell identity and regeneration. Semin Cell Dev Biol 72:10-18
Pasut, Alessandra; Chang, Natasha C; Gurriaran-Rodriguez, Uxia et al. (2016) Notch Signaling Rescues Loss of Satellite Cells Lacking Pax7 and Promotes Brown Adipogenic Differentiation. Cell Rep 16:333-343
Chang, Natasha C; Chevalier, Fabien P; Rudnicki, Michael A (2016) Satellite Cells in Muscular Dystrophy - Lost in Polarity. Trends Mol Med 22:479-496
Dumont, Nicolas A; Rudnicki, Michael A (2016) Targeting muscle stem cell intrinsic defects to treat Duchenne muscular dystrophy. NPJ Regen Med 1:
Jahani-Asl, Arezu; Yin, Hang; Soleimani, Vahab D et al. (2016) Control of glioblastoma tumorigenesis by feed-forward cytokine signaling. Nat Neurosci 19:798-806

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