Hes6 is required for actin cytoskeletal organization in differentiating C2C12 myoblasts

Exp Cell Res. 2011 Jul 1;317(11):1590-602. doi: 10.1016/j.yexcr.2011.03.023. Epub 2011 Apr 9.

Abstract

Hes6 is a member of the hairy-enhancer-of-split family of transcription factors that regulate proliferating cell fate in development and is known to be expressed in developing muscle. Here we investigate its function in myogenesis in vitro. We show that Hes6 is a direct transcriptional target of the myogenic transcription factors MyoD and Myf5, indicating that it is integral to the myogenic transcriptional program. The localization of Hes6 protein changes during differentiation, becoming predominantly nuclear. Knockdown of Hes6 mRNA levels by siRNA has no effect on cell cycle exit or induction of myosin heavy chain expression in differentiating C2C12 myoblasts, but F-actin filament formation is disrupted and both cell motility and myoblast fusion are reduced. The knockdown phenotype is rescued by expression of Hes6 cDNA resistant to siRNA. These results define a novel role for Hes6 in actin cytoskeletal dynamics in post mitotic myoblasts.

MeSH terms

  • Actins / physiology*
  • Animals
  • Base Sequence
  • Basic Helix-Loop-Helix Transcription Factors / antagonists & inhibitors
  • Basic Helix-Loop-Helix Transcription Factors / genetics
  • Basic Helix-Loop-Helix Transcription Factors / metabolism*
  • Blotting, Western
  • Cell Adhesion
  • Cell Differentiation*
  • Cell Movement
  • Cells, Cultured
  • Chromatin Immunoprecipitation
  • Cytoskeleton / physiology*
  • Fluorescent Antibody Technique
  • Gene Expression Regulation, Developmental
  • Mice
  • Mitosis
  • Molecular Sequence Data
  • Muscle Development
  • MyoD Protein / genetics
  • MyoD Protein / metabolism
  • Myoblasts / cytology*
  • Myoblasts / metabolism*
  • Myogenic Regulatory Factor 5 / genetics
  • Myogenic Regulatory Factor 5 / metabolism
  • RNA, Messenger / genetics
  • RNA, Small Interfering / genetics
  • Repressor Proteins / antagonists & inhibitors
  • Repressor Proteins / genetics
  • Repressor Proteins / metabolism*
  • Reverse Transcriptase Polymerase Chain Reaction
  • Sequence Homology, Nucleic Acid

Substances

  • Actins
  • Basic Helix-Loop-Helix Transcription Factors
  • Hes6 protein, mouse
  • Myf5 protein, mouse
  • MyoD Protein
  • MyoD1 myogenic differentiation protein
  • Myogenic Regulatory Factor 5
  • RNA, Messenger
  • RNA, Small Interfering
  • Repressor Proteins