Linear signaling in the Toll-Dorsal pathway of Drosophila: Activated pelle kinase specifies all threshold outputs of gene expression while the bHLH protein Twist specifies a subset

Angelike Stathopoulos, Michael Levine

Research output: Contribution to journalArticle

36 Scopus citations

Abstract

Differential activation of the Toll receptor leads to the formation of a broad Dorsal nuclear gradient that specifies at least three patterning thresholds of gene activity along the dorsoventral axis of precellular embryos. We investigate the activities of the Pelle kinase and Twist basic helix-loop-helix (bHLH) transcription factor in transducing Toll signaling. Pelle functions downstream of Toll to release Dorsal from the Cactus inhibitor. Twist is an immediate-early gene that is activated upon entry of Dorsal into nuclei. Transgenes misexpressing Pelle and Twist were introduced into different mutant backgrounds and the patterning activities were visualized using various target genes that respond to different thresholds of Toll-Dorsal signaling. These studies suggest that an anteroposterior gradient of Pelle kinase activity is sufficient to generate all known Toll-Dorsal patterning thresholds and that Twist can function as a gradient morphogen to establish at least two distinct dorsoventral patterning thresholds. We discuss how the Dorsal gradient system can be modified during metazoan evolution and conclude that Dorsal-Twist interactions are distinct from the interplay between Bicoid and Hunchback, which pattern the anteroposterior axis.

Original languageEnglish (US)
Pages (from-to)3411-3419
Number of pages9
JournalDevelopment
Volume129
Issue number14
StatePublished - Jul 1 2002
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Molecular Biology
  • Developmental Biology

Keywords

  • Dorsal
  • Dorsoventral pattering
  • Drosophila embryo
  • Gradient thresholds
  • Pelle
  • Twist

Fingerprint Dive into the research topics of 'Linear signaling in the Toll-Dorsal pathway of Drosophila: Activated pelle kinase specifies all threshold outputs of gene expression while the bHLH protein Twist specifies a subset'. Together they form a unique fingerprint.

Cite this