Ectopic expression of the proto-oncogene int-1 in Xenopus embryos leads to duplication of the embryonic axis

Cell. 1989 Sep 22;58(6):1075-84. doi: 10.1016/0092-8674(89)90506-0.


While there is convincing evidence implicating Drosophila int-1 in pattern regulation, the normal role of int-1 in vertebrate development is unclear. We have injected Xenopus eggs with mouse int-1 RNA and monitored subsequent development. Injected RNA is translated and the protein widely distributed. Embryos develop into apparently normal gastrulae, but almost all surviving neurulae have a bifurcated anterior and expanded posterior neural plate. Bifurcation of the neural plate was abolished by substitution of a single, conserved cysteine residue and was dependent on the presence of a signal peptide sequence in the int-1 protein. Histological examination indicates that underlying axial mesodermal structures were duplicated. This result suggests that ectopic int-1 expression leads to dual axis formation and points to a role for int-1 in patterning processes in vertebrate development.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Cloning, Molecular
  • DNA / genetics
  • Embryo, Nonmammalian / physiology*
  • Mice
  • Molecular Sequence Data
  • Nervous System / embryology*
  • Oocytes / cytology
  • Oocytes / physiology
  • Phenotype
  • Protein Biosynthesis
  • Protein Sorting Signals / genetics
  • Proto-Oncogene Proteins / genetics*
  • Proto-Oncogenes*
  • Transcription, Genetic*
  • Wnt Proteins
  • Wnt1 Protein
  • Xenopus / embryology*
  • Zebrafish Proteins*


  • Protein Sorting Signals
  • Proto-Oncogene Proteins
  • Wnt Proteins
  • Wnt1 Protein
  • Zebrafish Proteins
  • DNA