title: Leading edge-secreted Dpp cooperates with ACK-dependent signaling from the amnioserosa to regulate myosin levels during dorsal closure.
abstract: Dorsal closure of the Drosophila embryo is an epithelial fusion in which the epidermal flanks migrate to close a hole in the epidermis occupied by the amnioserosa, a process driven in part by myosin-dependent cell shape change. Dpp signaling is required for the morphogenesis of both tissues, where it promotes transcription of myosin from the zipper (zip) gene. Drosophila has two members of the activated Cdc42-associated kinase (ACK) family: DACK and PR2. Overexpression of DACK in embryos deficient in Dpp signaling can restore zip expression and suppress dorsal closure defects, while reducing the levels of DACK and PR2 simultaneously using mutations or amnioserosa-specific knock down by RNAi results in loss of zip expression. ACK function in the amnioserosa may generate a signal cooperating with Dpp secreted from the epidermis in driving zip expression in these two tissues, ensuring that cell shape changes in dorsal closure occur in a coordinated manner.
authors.affiliation: Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia, Canada.
authors.forename: Baharak
authors.initials: B
authors.lastname: Zahedi
authors.forename: Weiping
authors.initials: W
authors.lastname: Shen
authors.forename: Xing
authors.initials: X
authors.lastname: Xu
authors.forename: Xi
authors.initials: X
authors.lastname: Chen
authors.forename: Meena
authors.initials: M
authors.lastname: Mahey
authors.forename: Nicholas
authors.initials: N
authors.lastname: Harden
mesh_terms: D000818:Animals; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000196:embryology / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D009154:Mutation / Q000235:genetics; D018995:Myosin Heavy Chains / Q000235:genetics / Q000378:metabolism; D009218:Myosins / Q000378:metabolism*; D011505:Protein-Tyrosine Kinases / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: D029721:Drosophila Proteins; D008565:Membrane Proteins; C097862:Zip protein, Drosophila; C064196:dpp protein, Drosophila; D011505:Protein-Tyrosine Kinases; D018995:Myosin Heavy Chains; D009218:Myosins