Mis-specified cells die by an active gene-directed process, and inhibition of this death results in cell fate transformation in Drosophila

Development. 2005 Dec;132(24):5343-52. doi: 10.1242/dev.02150. Epub 2005 Nov 9.

Abstract

Incorrectly specified or mis-specified cells often undergo cell death or are transformed to adopt a different cell fate during development. The underlying cause for this distinction is largely unknown. In many developmental mutants in Drosophila, large numbers of mis-specified cells die synchronously, providing a convenient model for analysis of this phenomenon. The maternal mutant bicoid is particularly useful model with which to address this issue because its mutant phenotype is a combination of both transformation of tissue (acron to telson) and cell death in the presumptive head and thorax regions. We show that a subset of these mis-specified cells die through an active gene-directed process involving transcriptional upregulation of the cell death inducer hid. Upregulation of hid also occurs in oskar mutants and other segmentation mutants. In hid bicoid double mutants, mis-specified cells in the presumptive head and thorax survive and continue to develop, but they are transformed to adopt a different cell fate. We provide evidence that the terminal torso signaling pathway protects the mis-specified telson tissue in bicoid mutants from hid-induced cell death, whereas mis-specified cells in the head and thorax die, presumably because equivalent survival signals are lacking. These data support a model whereby mis-specification can be tolerated if a survival pathway is provided, resulting in cellular transformation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Body Patterning
  • Caspases / metabolism
  • Cell Death / physiology
  • Cell Differentiation / physiology
  • Cell Survival
  • Drosophila / embryology
  • Drosophila / genetics
  • Drosophila / physiology*
  • Drosophila Proteins / biosynthesis
  • Drosophila Proteins / genetics
  • Drosophila Proteins / physiology*
  • Embryo, Nonmammalian / cytology
  • Embryo, Nonmammalian / physiology
  • Enzyme Activation
  • Gene Expression Regulation, Developmental
  • Homeodomain Proteins / genetics
  • Homeodomain Proteins / physiology*
  • Mutation
  • Neuropeptides / biosynthesis
  • Neuropeptides / genetics
  • Neuropeptides / physiology*
  • Receptor Protein-Tyrosine Kinases / genetics
  • Receptor Protein-Tyrosine Kinases / physiology*
  • Signal Transduction
  • Trans-Activators / genetics
  • Trans-Activators / physiology*

Substances

  • Drosophila Proteins
  • HID protein, Drosophila
  • Homeodomain Proteins
  • Neuropeptides
  • Trans-Activators
  • bcd protein, Drosophila
  • osk protein, Drosophila
  • Receptor Protein-Tyrosine Kinases
  • tor protein, Drosophila
  • Caspases