title: Identification of a conserved set of upregulated genes in mouse skeletal muscle hypertrophy and regrowth.
abstract: The purpose of this study was to compare the gene expression profile of mouse skeletal muscle undergoing two forms of growth (hypertrophy and regrowth) with the goal of identifying a conserved set of differentially expressed genes. Expression profiling by microarray was performed on the plantaris muscle subjected to 1, 3, 5, 7, 10, and 14 days of hypertrophy or regrowth following 2 wk of hind-limb suspension. We identified 97 differentially expressed genes (≥2-fold increase or ≥50% decrease compared with control muscle) that were conserved during the two forms of muscle growth. The vast majority (∼90%) of the differentially expressed genes was upregulated and occurred at a single time point (64 out of 86 genes), which most often was on the first day of the time course. Microarray analysis from the conserved upregulated genes showed a set of genes related to contractile apparatus and stress response at day 1, including three genes involved in mechanotransduction and four genes encoding heat shock proteins. Our analysis further identified three cell cycle-related genes at day and several genes associated with extracellular matrix (ECM) at both days 3 and 10. In conclusion, we have identified a core set of genes commonly upregulated in two forms of muscle growth that could play a role in the maintenance of sarcomere stability, ECM remodeling, cell proliferation, fast-to-slow fiber type transition, and the regulation of skeletal muscle growth. These findings suggest conserved regulatory mechanisms involved in the adaptation of skeletal muscle to increased mechanical loading.
authors.affiliation: Center for Muscle Biology, University of Kentucky, Lexington, Kentucky; Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky;
authors.forename: Thomas
authors.initials: T
authors.lastname: Chaillou
authors.affiliation: Center for Muscle Biology, University of Kentucky, Lexington, Kentucky; Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky; Department of Rehabilitation Sciences, College of Health Sciences, University of Kentucky, Lexington, Kentucky.
authors.forename: Janna R
authors.initials: JR
authors.lastname: Jackson
authors.affiliation: Center for Muscle Biology, University of Kentucky, Lexington, Kentucky; Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky;
authors.forename: Jonathan H
authors.initials: JH
authors.lastname: England
authors.affiliation: Center for Muscle Biology, University of Kentucky, Lexington, Kentucky; Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky; Department of Rehabilitation Sciences, College of Health Sciences, University of Kentucky, Lexington, Kentucky.
authors.forename: Tyler J
authors.initials: TJ
authors.lastname: Kirby
authors.affiliation: Department of Rehabilitation Sciences, College of Health Sciences, University of Kentucky, Lexington, Kentucky.
authors.forename: Jena
authors.initials: J
authors.lastname: Richards-White
authors.affiliation: Center for Muscle Biology, University of Kentucky, Lexington, Kentucky; Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky;
authors.forename: Karyn A
authors.initials: KA
authors.lastname: Esser
authors.affiliation: Center for Muscle Biology, University of Kentucky, Lexington, Kentucky; Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky; Department of Rehabilitation Sciences, College of Health Sciences, University of Kentucky, Lexington, Kentucky.
authors.forename: Esther E
authors.initials: EE
authors.lastname: Dupont-Versteegden
authors.affiliation: Center for Muscle Biology, University of Kentucky, Lexington, Kentucky; Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky; jjmcca2@email.uky.edu.
authors.forename: John J
authors.initials: JJ
authors.lastname: McCarthy
mesh_terms: D000818:Animals; D015536:Down-Regulation; D020869:Gene Expression Profiling; D019417:Hindlimb Suspension; D006984:Hypertrophy / Q000235:genetics* / Q000378:metabolism; D008297:Male; D051379:Mice; D024510:Muscle Development / Q000235:genetics*; D018482:Muscle, Skeletal / Q000378:metabolism*; D009135:Muscular Diseases / Q000235:genetics* / Q000378:metabolism; D059467:Transcriptome; D015854:Up-Regulation
keywords: extracellular matrix; hind-limb suspension; mechanotransduction; stress response; transcriptome