The Drosophila Shark tyrosine kinase is required for embryonic dorsal closure
AUTOR(ES)
Fernandez, Rafael
FONTE
Cold Spring Harbor Laboratory Press
RESUMO
Dorsal closure (DC) in the Drosophila embryo requires the coordinated interaction of two different functional domains of the epidermal cell layer—the leading edge (LE) and the lateral epidermis. In response to activation of a conserved c-Jun amino-terminal kinase (JNK) signaling module, the dorsal-most layer of cells, which constitute the LE of the stretching epithelial sheet, secrete Dpp, a member of the TGFβ superfamily. Dpp and other LE cell-derived signaling molecules stimulate the bilateral dorsal elongation of cells of the dorsolateral epidermis over the underlaying amnioserosa and the eventual fusion of their LEs along the dorsal midline. We have found that flies bearing a Shark tyrosine kinase gene mutation, shark1, exhibit a DC-defective phenotype. Dpp fails to be expressed in shark1 mutant LE cells. Consistent with these observations, epidermal-specific reconstitution of shark function or overexpression of an activated form of c-Jun in the shark1 mutant background, rescues the DC defect. Thus, Shark regulates the JNK signaling pathway leading to Dpp expression in LE cells. Furthermore, constitutive activation of the Dpp pathway throughout the epidermis fails to rescue the shark1 DC defect, suggesting that Shark may function in additional pathways in the LE and/or lateral epithelium.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=316420Documentos Relacionados
- The Drosophila Pkn protein kinase is a Rho/Rac effector target required for dorsal closure during embryogenesis
- The Drosophila Ste20-related kinase misshapen is required for embryonic dorsal closure and acts through a JNK MAPK module on an evolutionarily conserved signaling pathway
- ACK Family Tyrosine Kinase Activity Is a Component of Dcdc42 Signaling during Dorsal Closure in Drosophila melanogaster
- The Drosophila Bruton’s Tyrosine Kinase (Btk) Homolog Is Required for Adult Survival and Male Genital Formation
- The Cre-Binding Protein Dcreb-a Is Required for Drosophila Embryonic Development