Absence of Developmental and Unconventional Myosin Heavy Chain in Human Suprahyoid Muscles

• Type of Material: Article
• Authors: Qingwei Luo, Emory University; Megan Douglas, Emory University; Thomas Burkholder, Georgia Institute of Technology; Alan Sokoloff, Emory University
• Language: English
• Date: 2014-04-01
• Publisher: Wiley: 12 months
• Publication Version: Author Accepted Manuscript (After Peer Review)
• Copyright Statement: © 2013 Wiley Periodicals, Inc.
• Final Published Version (URL): http://dx.doi.org/10.1002/mus.23946
• Title of Journal or Parent Work: Muscle and Nerve
• ISSN: 0148-639X
• Volume: 49
• Issue: 4
• Start Page: 534
• End Page: 544
• Grant/Funding Information: Human tissue was kindly provided by the Emory University School of Medicine Body Donor Program or purchased from the National Disease Research Interchange.; This work was supported by grant DC005017 from the National Institute on Deafness and Other Communication Disorders to Dr. Alan J. Sokoloff.; Non-human primate tissue was purchased from the California National Primate Research Center (Research Center Base Grant RR00169, National Center for Research Resources, NIH).
• Keywords: Science & Technology; Life Sciences & Biomedicine; Clinical Neurology; muscle; MASTICATORY MUSCLES; swallowing; HUMAN DIGASTRIC MUSCLE; HUMAN LARYNGEAL MUSCLES; HUMAN MYLOHYOID MUSCLE; EXTRAOCULAR-MUSCLE; SKELETAL-MUSCLE; Neurosciences; myosin heavy chain; suprahyoid; Neurosciences & Neurology; SLOW MYOSIN; ELECTROPHORETIC SEPARATION; human; DIFFERENTIAL EXPRESSION; FIBER-TYPE
• Research Categories: Biology, Physiology

Abstract

Introduction: Contradictory reports of the myosin heavy chain (MHC) composition of adult human suprahyoid muscles leave unresolved the extent to which these muscles express developmental and unconventional MHC. Methods: By immunohistochemistry, separation sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE)-Coomassie, separation SDS-PAGE-Western blot, and mRNA PCR, we tested for conventional MHCI, MHCIIA, MHCIIX, developmental MHC embryonic and MHC neonatal, and unconventional MHC alpha-cardiac, MHC extraocular, and MHC slow tonic in adult human anterior digastric (AD), geniohyoid (GH), and mylohyoid (MH) muscles. Results: By separation SDS-PAGE-Coomassie and Western blot, only conventional MHC are present. By immunohistochemistry all muscle fibers are positive for MHCI, MHCIIA, or MHCIIX, and fewer than 4 fibers/mm2 are positive for developmental or unconventional MHC. By PCR, mRNA of MHCI and MHCIIA dominate, with sporadically detectable MHC alpha-cardiac and without detectable mRNA of other developmental and unconventional MHC. Conclusions: We conclude that human suprahyoid muscles AD, GH, and MH are composed almost exclusively of conventional MHC isoforms.