Longitudinal variation in muscle protein expression and contraction kinetics of largemouth bass axial muscle.

Journal Article

The present study investigates muscle protein expression in largemouth bass Micropterus salmoides through intra- and intermyomeric comparisons of white muscle. Using denaturing SDS-polyacrylamide gel electrophoresis, muscle protein expression in the arm and cone regions of sequential myomeres was compared for three bass. Low percentage (4.75 %) polyacrylamide-SDS gels and cyanogen bromide (CNBr) peptide mapping revealed no obvious intramyomeric differences between the myosin heavy chains of the arm and cone regions. Electrophoresis of myofibrils and muscle homogenates on higher percentage gels also failed to demonstrate any significant differences between arm and cone regions in either the myosin light chains or any of the major insoluble and soluble contractile proteins. Two differences were discovered intermyomerically: (i) the ratio of two troponin T isoforms changed from head to tail and (ii) caudal muscle had a lower total parvalbumin content than rostral muscle. Since troponin T and parvalbumin have been implicated in the regulation of skeletal muscle kinetics, longitudinal variation in muscle contraction kinetics was predicted. Subsequent experiments revealed that bass rostral white muscle showed faster rates of activation and relaxation than more caudal muscle, as has been observed in white muscle of other fish species. Rostral-caudal variations in white muscle protein composition and contractile properties are predicted to affect patterns of power production during fast, unsteady swimming.

Full Text

Duke Authors

Cited Authors

  • Thys, TM; Blank, JM; Coughlin, DJ; Schachat, F

Published Date

  • December 2001

Published In

Volume / Issue

  • 204 / Pt 24

Start / End Page

  • 4249 - 4257

PubMed ID

  • 11815649

International Standard Serial Number (ISSN)

  • 0022-0949

Language

  • eng

Conference Location

  • England