Gli2 and Gli3 play distinct roles in the dorsoventral patterning of the mouse hindbrain

Dev Biol. 2007 Feb 1;302(1):345-55. doi: 10.1016/j.ydbio.2006.08.005. Epub 2006 Aug 9.

Abstract

Sonic Hedgehog (Shh) signaling plays a critical role during dorsoventral (DV) patterning of the developing neural tube by modulating the expression of neural patterning genes. Overlapping activator functions of Gli2 and Gli3 have been shown to be required for motoneuron development and correct neural patterning in the ventral spinal cord. However, the role of Gli2 and Gli3 in ventral hindbrain development is unclear. In this paper, we have examined DV patterning of the hindbrain of Shh(-/-), Gli2(-/-) and Gli3(-/-) embryos, and found that the respective role of Gli2 and Gli3 is not only different between the hindbrain and spinal cord, but also at distinct rostrocaudal levels of the hindbrain. Remarkably, the anterior hindbrain of Gli2(-/-) embryos displays ventral patterning defects as severe as those observed in Shh(-/-) embryos suggesting that, unlike in the spinal cord and posterior hindbrain, Gli3 cannot compensate for the loss of Gli2 activator function in Shh-dependent ventral patterning of the anterior hindbrain. Loss of Gli3 also results in a distinct patterning defect in the anterior hindbrain, including dorsal expansion of Nkx6.1 expression. Furthermore, we demonstrate that ventral patterning of rhombomere 4 is less affected by loss of Gli2 function revealing a different requirement for Gli proteins in this rhombomere. Taken together, these observations indicate that Gli2 and Gli3 perform rhombomere-specific function during DV patterning of the hindbrain.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Body Patterning*
  • Gene Expression Regulation, Developmental*
  • Hedgehog Proteins / metabolism
  • Kruppel-Like Transcription Factors / genetics
  • Kruppel-Like Transcription Factors / metabolism*
  • Mice
  • Mice, Inbred Strains
  • Nerve Tissue Proteins / genetics
  • Nerve Tissue Proteins / metabolism*
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism*
  • Rhombencephalon / cytology
  • Rhombencephalon / embryology*
  • Signal Transduction
  • Spinal Cord / cytology
  • Spinal Cord / embryology
  • Zinc Finger Protein Gli2
  • Zinc Finger Protein Gli3

Substances

  • GLI2 protein, human
  • GLI3 protein, human
  • Hedgehog Proteins
  • Kruppel-Like Transcription Factors
  • Nerve Tissue Proteins
  • Nuclear Proteins
  • Shh protein, mouse
  • Zinc Finger Protein Gli2
  • Zinc Finger Protein Gli3