Generating Patterns From Fields of Cells. Examples From Drosophila Segmentation

EMBO Rep. 2001 Dec;2(12):1083-8. doi: 10.1093/embo-reports/kve255.

Abstract

In Drosophila, a cascade of maternal, gap, pair-rule and segment polarity genes subdivides the antero/posterior axis of the embryo into repeating segmental stripes. This review summarizes what happens next, i.e. how an intrasegmental pattern is generated and controls the differentiation of specific cell types in the epidermis. Within each segment, cells secreting the signalling molecules Wingless (the homologue of vertebrate Wnt-1) and Hedgehog are found in narrow stripes on both sides of the parasegmental boundary. The Wingless and Hedgehog organizing activities help to establish two more stripes per segment that localize ligands for the Epidermal Growth Factor and the Notch signalling pathways, respectively. These four signals then act at short range and in concert to control epidermal differentiation at the single cell level across the segment. This example from Drosophila provides a paradigm for how organizers generate precise patterns, and ultimately different cell types, in a naïve field of cells.

Publication types

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

MeSH terms

  • Animals
  • Body Patterning*
  • Cell Differentiation / genetics
  • Drosophila / cytology*
  • Drosophila / embryology*
  • Drosophila / genetics
  • Drosophila Proteins / metabolism
  • Epidermal Cells
  • Gene Expression Regulation, Developmental
  • Hedgehog Proteins
  • Ligands
  • Proto-Oncogene Proteins / genetics
  • Proto-Oncogene Proteins / metabolism
  • Transcription, Genetic / genetics
  • Wnt1 Protein

Substances

  • Drosophila Proteins
  • Hedgehog Proteins
  • Ligands
  • Proto-Oncogene Proteins
  • Wnt1 Protein
  • wg protein, Drosophila
  • hh protein, Drosophila