TitleContext-dependent transcriptional interpretation of mitogen activated protein kinase signaling in the Drosophila embryo.
Publication TypeJournal Article
Year of Publication2013
AuthorsKim, Y, Iagovitina, A, Ishihara, K, Fitzgerald, KM, Deplancke, B, Papatsenko, D, Shvartsman, SY
Date Published2013 Jun
KeywordsAnimals, Base Sequence, Drosophila melanogaster, Drosophila Proteins, Embryo, Nonmammalian, Enhancer Elements, Genetic, Gene Expression Regulation, Developmental, MAP Kinase Signaling System, Mitogen-Activated Protein Kinases, Models, Genetic, Molecular Sequence Data, Repressor Proteins, Transcription, Genetic

Terminal regions of the Drosophila embryo are patterned by the localized activation of Mitogen Activated Protein Kinase (MAPK), which induces zygotic genes through relief of their repression by transcriptional repressor Capicua. The levels of MAPK activation at the anterior and posterior termini are close to each other, but the expression patterns of MAPK-target genes, such as zerknüllt (zen) and tailless (tll), display strong anterior-posterior (AP) asymmetry. This region-specific response to MAPK activation provides a clear example of context-dependent interpretation of inductive signaling, a common developmental effect that remains poorly understood. In the past, the AP asymmetry of zen expression was attributed to a mechanism that depends on MAPK substrate competition. We present data suggesting that the asymmetric expression of tll is generated by a different mechanism, based on feedforward control and multiple enhancers of the tll gene. A simple mathematical model of this mechanism correctly predicts how the wild-type expression pattern of tll changes in mutants affecting the anterior, dorsoventral, and terminal patterning systems and some of their direct targets.

Alternate JournalChaos