Hoxa-11 and Hoxa-13 are involved in repression of MyoD during limb muscle development

Dev Growth Differ. 2003 Oct-Dec;45(5-6):485-98. doi: 10.1111/j.1440-169x.2003.00715.x.

Abstract

Under the influence of the limb mesenchyme, Hoxa-11 is expressed in migrating and proliferating premyoblasts in the limb field and Hoxa-13 is induced in subdomains of congregated limb muscle masses. To evaluate the roles of Hoxa-11 and Hoxa-13 in myogenesis of the limb, we performed electroporation in ovo to force expression of these Hox genes in limb muscle precursors. In the presence of ectopic Hoxa-11, expression of MyoD was blocked transiently. In C2C12 myoblasts, transfection of Hoxa-11 also repressed the expression of endogenous MyoD. Forced expression of Hoxa-13 resulted in more pronounced repression of MyoD in both limb and C2C12 myoblasts. In contrast, targeted disruption of Hoxa-13 gave rise to enhanced expression of MyoD in the flexor carpi radialis muscle, a forearm muscle that normally expressed Hoxa-13. These results suggest that Hoxa-11 and Hoxa-13 are involved in the negative regulation of MyoD expression in limb muscle precursors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Body Patterning
  • Cell Line
  • Chick Embryo
  • Chickens
  • Codon
  • DNA, Complementary / metabolism
  • Electroporation
  • Extremities / embryology*
  • Gene Expression Regulation, Developmental
  • Homeodomain Proteins / physiology*
  • Immunohistochemistry
  • In Situ Hybridization
  • Mice
  • Muscles / embryology*
  • MyoD Protein / metabolism*
  • Protein Structure, Tertiary
  • Time Factors
  • Transfection

Substances

  • Codon
  • DNA, Complementary
  • Homeodomain Proteins
  • Hoxa11 protein, mouse
  • MyoD Protein
  • homeobox protein HOXA13