Interference with function of a homeobox gene in Xenopus embryos produces malformations of the anterior spinal cord

Cell. 1989 Oct 6;59(1):81-93. doi: 10.1016/0092-8674(89)90871-4.


XIHbox 1 is expressed in a narrow band across the cervical region of Xenopus embryos. The gene produces two related proteins: "long" and "short" XIHbox 1 homeodomain proteins. Injection of antibodies to the long XIHbox 1 protein into 1-cell embryos caused a phenotype in which the anterior spinal cord was morphologically transformed into a hindbrain-like structure. This alteration was restricted to the region normally expressing long XIHbox 1 protein. Injection of long protein mRNA disrupted segmentation and tissue organization without inhibiting cell proliferation. Injection of short protein mRNA into 1-cell embryos produced spinal cord malformations similar, but not identical, to those caused by the antibodies, suggesting antagonistic roles for long and short XIHbox 1 proteins. We immunostained tadpoles carrying extended hindbrains for N-CAM and consistently found defective organization of spinal nerves over the affected region.

Publication types

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

MeSH terms

  • Animals
  • Antibodies / administration & dosage
  • DNA-Binding Proteins / biosynthesis
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / immunology
  • Embryo, Nonmammalian / abnormalities*
  • Embryo, Nonmammalian / analysis
  • Genes, Homeobox*
  • Homeodomain Proteins*
  • Microinjections
  • Morphogenesis
  • Mutation
  • Neoplasm Proteins*
  • Phenotype
  • Rhombencephalon / abnormalities
  • Rhombencephalon / embryology
  • Spinal Cord / abnormalities*
  • Spinal Cord / analysis
  • Spinal Cord / embryology
  • Spinal Nerve Roots / abnormalities
  • Staining and Labeling
  • Xenopus Proteins*
  • Xenopus laevis / embryology
  • Xenopus laevis / genetics*


  • Antibodies
  • DNA-Binding Proteins
  • Homeodomain Proteins
  • Hoxa7 protein, Xenopus
  • Neoplasm Proteins
  • Xenopus Proteins