Evolution of neuroblast identity: seven-up and prospero expression reveal homologous and divergent neuroblast fates in Drosophila and Schistocerca

Development. 1995 Dec;121(12):3989-96. doi: 10.1242/dev.121.12.3989.

Abstract

In the Drosophila CNS, early neuroblast formation and fate are controlled by the pair-rule class of segmentation genes. The distantly related Schistocerca (grasshopper) embryo has a similar arrangement of neuroblasts, despite lack of known pair-rule gene function. Does divergent pair-rule gene function lead to different neuroblast identities, or can different patterning mechanisms produce homologous neuroblasts? We use four molecular markers to compare Drosophila and Schistocerca neuroblast identity: seven-up, prospero, engrailed, and fushi-tarazu/Dax. In both insects some early-forming neuroblasts share key features of neuroblast identity (position, time of formation, and temporally accurate gene expression); thus, different patterning mechanisms can generate similar neuroblast fates. In contrast, several later-forming neuroblasts show species-specific differences in position and/or gene expression; these neuroblast identities seem to have diverged, suggesting that evolution of the insect central nervous system can occur through changes in embryonic neuroblast identity.

Publication types

  • Comparative Study
  • 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
  • Biological Evolution*
  • Cell Differentiation / genetics
  • Central Nervous System / embryology*
  • Conserved Sequence
  • DNA-Binding Proteins / physiology*
  • Drosophila / embryology*
  • Drosophila / genetics*
  • Drosophila Proteins*
  • Gene Expression
  • Genetic Markers
  • Grasshoppers / embryology*
  • Grasshoppers / genetics
  • Humans
  • Immunohistochemistry
  • In Situ Hybridization
  • Molecular Sequence Data
  • Nerve Tissue Proteins / physiology*
  • Neurons / physiology*
  • Nuclear Proteins / physiology*
  • Receptors, Steroid / physiology*
  • Sequence Alignment
  • Transcription Factors*

Substances

  • DNA-Binding Proteins
  • Drosophila Proteins
  • Genetic Markers
  • Nerve Tissue Proteins
  • Nuclear Proteins
  • Receptors, Steroid
  • Transcription Factors
  • pros protein, Drosophila
  • svp protein, Drosophila

Associated data

  • GENBANK/U36622