title: Human skeletal muscle fiber type specific protein content.
abstract: The aim of this project was to develop a method to assess fiber type specific protein content across the continuum of human skeletal muscle fibers. Individual vastus lateralis muscle fibers (n = 264) were clipped into two portions: one for sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) fiber typing and one for Western blot protein identification. Following fiber type determination, fiber segments were combined into fiber type specific pools (∼20 fibers/pool) and measured for total protein quantity, glyceraldehyde 3-phosphate dehydrogenase (GAPDH), citrate synthase (CS), and total p38 content. GAPDH content was 64, 54, 160, and 138% more abundant in myosin heavy chain (MHC) I/IIa, MHC IIa, MHC IIa/IIx, and MHC IIx fibers, respectively, when compared with MHC I. Inversely, CS content was 528, 472, 242, and 47% more abundant in MHC I, MHC I/IIa, MHC IIa, and MHC IIa/IIx fibers, respectively, when compared with MHC IIx. Total p38 content was 87% greater in MHC IIa versus MHC I fibers. These data and this approach establish a reliable method for human skeletal muscle fiber type specific protein analysis. Initial results show that particular proteins exist in a hierarchal fashion throughout the continuum of human skeletal muscle fiber types, further highlighting the necessity of fiber type specific analysis.
authors.affiliation: Human Performance Laboratory, Ball State University, Muncie, IN 47306, USA.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Galpin
authors.forename: Ulrika
authors.initials: U
authors.lastname: Raue
authors.forename: Bozena
authors.initials: B
authors.lastname: Jemiolo
authors.forename: Todd A
authors.initials: TA
authors.lastname: Trappe
authors.forename: Matthew P
authors.initials: MP
authors.lastname: Harber
authors.forename: Kiril
authors.initials: K
authors.lastname: Minchev
authors.forename: Scott
authors.initials: S
authors.lastname: Trappe
mesh_terms: D015153:Blotting, Western; D002950:Citrate (si)-Synthase / Q000032:analysis; D004591:Electrophoresis, Polyacrylamide Gel; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000032:analysis; D006801:Humans; D018485:Muscle Fibers, Skeletal / Q000378:metabolism*; D018995:Myosin Heavy Chains / Q000378:metabolism; D011506:Proteins / Q000032:analysis*; D048051:p38 Mitogen-Activated Protein Kinases / Q000032:analysis
chemical_list: D011506:Proteins; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases; D002950:Citrate (si)-Synthase; D048051:p38 Mitogen-Activated Protein Kinases; D018995:Myosin Heavy Chains