The Tribolium columnar genes reveal conservation and plasticity in neural precursor patterning along the embryonic dorsal-ventral axis

Dev Biol. 2005 Mar 15;279(2):491-500. doi: 10.1016/j.ydbio.2004.12.031.

Abstract

The Drosophila columnar genes are key regulators of neural precursor formation and patterning along the dorsal-ventral axis of the developing CNS and include ventral nerve cord defective (vnd), intermediate nerve cord defective (ind), muscle segment homeodomain (msh), and Epidermal growth factor receptor (Egfr). To investigate the evolution of neural pattern formation, we identified and determined the expression patterns of Tribolium vnd, ind, and msh, and found that they are expressed in the medial, intermediate, and lateral columns of the developing CNS, respectively, in patterns similar, but not identical, to their Drosophila orthologs. The pattern of Egfr activity suggests that the genetic regulatory mechanisms that initiate Tc-vnd expression are similar in Drosophila and Tribolium, whereas those that initiate Tc-ind have diverged. RNAi analyses of gene function show that Tc-vnd and Tc-ind promote the formation of medial and intermediate column neural precursors and that vnd-mediated repression of ind establishes the boundary between the medial and intermediate columns. These data suggest that columnar gene expression and function underlie neural pattern formation in Drosophila, Tribolium, and potentially all insects, but that subtle spatiotemporal differences in expression of these genes may produce species-specific morphological differences.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Body Patterning / genetics*
  • Cell Lineage
  • Central Nervous System / anatomy & histology
  • Central Nervous System / embryology
  • Drosophila Proteins / genetics
  • Drosophila Proteins / metabolism
  • ErbB Receptors / genetics
  • ErbB Receptors / metabolism
  • Homeodomain Proteins / genetics
  • Homeodomain Proteins / metabolism
  • Insect Proteins / genetics
  • Insect Proteins / metabolism
  • Molecular Sequence Data
  • Morphogenesis / physiology
  • Neurons / cytology
  • Neurons / physiology*
  • Protein Kinases / genetics
  • Protein Kinases / metabolism
  • RNA Interference
  • Receptors, Invertebrate Peptide / genetics
  • Receptors, Invertebrate Peptide / metabolism
  • Sequence Alignment
  • Stem Cells / cytology
  • Stem Cells / physiology*
  • Transcription Factors / genetics
  • Transcription Factors / metabolism
  • Tribolium / embryology*
  • Tribolium / genetics*

Substances

  • Dr protein, Drosophila
  • Drosophila Proteins
  • Homeodomain Proteins
  • IND protein, Drosophila
  • Insect Proteins
  • Receptors, Invertebrate Peptide
  • Transcription Factors
  • vnd protein, Drosophila
  • Protein Kinases
  • Egfr protein, Drosophila
  • ErbB Receptors

Associated data

  • GENBANK/AY695256
  • GENBANK/AY695257
  • GENBANK/AY695258