Transcription of muscle-specific actin genes in early Xenopus development: nuclear transplantation and cell dissociation

Cell. 1984 Oct;38(3):691-700. doi: 10.1016/0092-8674(84)90264-2.


Cloned cDNA probes that recognize muscle-specific alpha-actin gene transcripts have been used to analyze two kinds of experimental embryos in Xenopus. In one, genetically marked nuclei of larval muscle cells were transplanted to wild-type enucleated eggs; alpha-actin genes became transcriptionally inactive in the resulting blastulae but were reactivated when these embryos reached the normal stage of alpha-actin expression (late gastrula). In the other, blastula embryos reared from fertilized eggs were separated into animal, vegetal, and equatorial regions, and their cells dissociated and reaggregated. alpha-Actin RNA was synthesized at the normal time in development, but only by equatorial cells. We conclude that alpha-actin gene transcription is normally regulated in nuclear-transplant embryos and is undisturbed by the absence of cell contacts during cleavage.

Publication types

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

MeSH terms

  • Actins / genetics*
  • Animals
  • Blastocyst / cytology
  • Cell Aggregation
  • Cell Communication
  • Cell Division
  • Cell Nucleus / physiology*
  • Embryo, Nonmammalian / physiology
  • Female
  • Fertilization
  • Genes*
  • Muscles / embryology*
  • Muscles / metabolism
  • Nuclear Transfer Techniques
  • Nucleic Acid Hybridization
  • Transcription, Genetic*
  • Xenopus


  • Actins