title: Drosophila DOCK family protein sponge regulates the JNK pathway during thorax development.
abstract: The dedicator of cytokinesis (DOCK) family proteins that are conserved in a wide variety of species are known as DOCK1-DOCK11 in mammals. The Sponge (Spg) is a Drosophila counterpart to the mammalian DOCK3. Specific knockdown of spg by pannir-GAL4 or apterous-GAL4 driver in wing discs induced split thorax phenotype in adults. Reduction of the Drosophila c-Jun N-terminal kinase (JNK), basket (bsk) gene dose enhanced the spg knockdown-induced phenotype. Conversely, overexpression of bsk suppressed the split thorax phenotype. Monitoring JNK activity in the wing imaginal discs by immunostaining with anti-phosphorylated JNK (anti-pJNK) antibody together with examination of lacZ expression in a puckered-lacZ enhancer trap line revealed the strong reduction of the JNK activity in the spg knockdown clones. This was further confirmed by Western immunoblot analysis of extracts from wing discs of spg knockdown fly with anti-pJNK antibody. Furthermore, the Duolink in situ Proximity Ligation Assay method detected interaction signals between Spg and Rac1 in the wing discs. Taken together, these results indicate Spg positively regulates JNK pathway that is required for thorax development and the regulation is mediated by interaction with Rac1.
authors.affiliation: Department of Applied Biology, Kyoto Institute of Technology.
authors.forename: Kazushige
authors.initials: K
authors.lastname: Morishita
authors.forename: Fumito
authors.initials: F
authors.lastname: Ozasa
authors.forename: Koichi
authors.initials: K
authors.lastname: Eguchi
authors.forename: Yasuhide
authors.initials: Y
authors.lastname: Yoshioka
authors.forename: Hideki
authors.initials: H
authors.lastname: Yoshida
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Hiai
authors.forename: Masamitsu
authors.initials: M
authors.lastname: Yamaguchi
mesh_terms: D000818:Animals; D002352:Carrier Proteins / Q000502:physiology*; D029721:Drosophila Proteins / Q000378:metabolism / Q000502:physiology*; D004331:Drosophila melanogaster / Q000254:growth & development* / Q000378:metabolism; D005260:Female; D055785:Gene Knockdown Techniques; D060227:Imaginal Discs / Q000378:metabolism; D007814:Larva / Q000254:growth & development / Q000378:metabolism; D020935:MAP Kinase Signaling System; D008297:Male; D009928:Organ Specificity; D010641:Phenotype; D020744:rac GTP-Binding Proteins / Q000378:metabolism
chemical_list: D002352:Carrier Proteins; D029721:Drosophila Proteins; C090146:Rac1 protein, Drosophila; C559918:Spg protein, Drosophila; D020744:rac GTP-Binding Proteins