Efficient hormone-inducible protein function in Xenopus laevis

Dev Biol. 1995 Sep;171(1):267-72. doi: 10.1006/dbio.1995.1279.


A major problem in analyzing gene function during Xenopus development has been the inability to induce gene expression in a temporally controlled manner. We have attempted to solve this problem with a system of hormone-activated protein function, using the myogenic gene MyoD as a paradigm. We show that microinjection of RNA for MyoD fused to the ligand-binding domain of either the estrogen or glucocorticoid receptor results in hormone-dependent activation of MyoD function, as assayed by ectopic induction of muscle-specific actin mRNA. Induction is tightly regulated in both isolated animal caps and intact embryos, with ectopic muscle-specific actin expression inducible after 2 hr of hormone treatment. Higher levels of MyoD-receptor fusion proteins that native MyoD protein are present in embryos, apparently a result of increased fusion protein stability. This is the first demonstration that hormone-inducible fusion proteins can work effectively in a complex embryo.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Embryo, Nonmammalian
  • Estrogens / physiology
  • Gene Expression Regulation, Developmental*
  • Glucocorticoids / physiology
  • MyoD Protein / genetics*
  • MyoD Protein / metabolism
  • Receptors, Estrogen / genetics*
  • Receptors, Estrogen / metabolism
  • Receptors, Glucocorticoid / genetics*
  • Receptors, Glucocorticoid / metabolism
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism
  • Xenopus laevis


  • Estrogens
  • Glucocorticoids
  • MyoD Protein
  • Receptors, Estrogen
  • Receptors, Glucocorticoid
  • Recombinant Fusion Proteins