Overexpression of Xgsk-3 disrupts anterior ectodermal patterning in Xenopus

Dev Biol. 1996 May 1;175(2):256-64. doi: 10.1006/dbio.1996.0113.


The Xenopus homolog of glycogen synthase kinase-3, Xgsk-3, plays a major role in regulating the formation of the dorsal-ventral axis, most likely through effects on the mesoderm. To determine whether Xgsk-3 is involved in ectodermal patterning, Xgsk-3 was ectopically overexpressed in the presumptive ectoderm. This approach resulted in a dramatically expanded cement gland, which is due to early changes in cement gland specification at the anterior end of the embryo. Explant experiments were used to show that Xgsk-3 overexpression enhances the response of ectoderm to cement-gland-inducing signals from the mesoderm and to the intercellular signaling factor noggin. Expression of two other noggin-inducible genes, Xotx2 and XANF-2, was also expanded in whole embryos, while the expression of the epidermal marker, Xgbx-2, was eliminated. These results suggest that Xgsk-3 may play a role in anterior ectodermal patterning as a component of an intracellular pathway that regulates the ectodermal responsiveness to endogenous inducing signals.

Publication types

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

MeSH terms

  • Animals
  • Calcium-Calmodulin-Dependent Protein Kinases / genetics
  • Calcium-Calmodulin-Dependent Protein Kinases / physiology*
  • Carrier Proteins
  • Ectoderm / ultrastructure*
  • Embryo, Nonmammalian / enzymology
  • Embryo, Nonmammalian / ultrastructure
  • Embryonic Development
  • Embryonic Induction / physiology*
  • Enzyme Induction
  • Epidermis / embryology
  • Gene Expression Regulation, Developmental*
  • Genetic Vectors
  • Glycogen Synthase Kinase 3
  • Glycogen Synthase Kinases
  • Head / abnormalities
  • Head / embryology*
  • Mesoderm / physiology
  • Microinjections
  • Nervous System / embryology
  • Proteins / physiology
  • RNA, Messenger / administration & dosage
  • RNA, Messenger / genetics
  • Recombinant Fusion Proteins / metabolism
  • Signal Transduction
  • Xenopus laevis / embryology*
  • Xenopus laevis / genetics


  • Carrier Proteins
  • Proteins
  • RNA, Messenger
  • Recombinant Fusion Proteins
  • noggin protein
  • Glycogen Synthase Kinases
  • Calcium-Calmodulin-Dependent Protein Kinases
  • Glycogen Synthase Kinase 3