title: The BED finger domain protein MIG-39 halts migration of distal tip cells in Caenorhabditis elegans.
abstract: Organs are often formed by the extension and branching of epithelial tubes. An appropriate termination of epithelial tube extension is important for generating organs of the proper size and morphology. However, the mechanism by which epithelial tubes terminate their extension is mostly unknown. Here we show that the BED-finger domain protein MIG-39 acts to stop epithelial tube extension in Caenorhabditis elegans. The gonadal leader cells, called distal tip cells (DTCs), migrate in a U-shaped pattern during larval development and stop migrating at the young adult stage, generating a gonad with anterior and posterior U-shaped arms. In mig-39 mutants, however, DTCs overshot their normal stopping position. MIG-39 promoted the deceleration of DTCs, leading to the proper timing and positioning of the cessation of DTC migration. Among three Rac GTPase genes, mutations in ced-10 and rac-2 enhanced the overshoot of anterior DTCs, while they suppressed that of posterior DTCs of mig-39 mutants. On the other hand, the mutation in mig-2 suppressed both the anterior and posterior DTC defects of mig-39. Genetic analyses suggested that MIG-39 acts in parallel with Rac GTPases in stopping DTC migration. We propose a model in which the anterior and posterior DTCs respond in an opposite manner to the levels of Rac activities in the cessation of DTC migration.
authors.affiliation: Department of Bioscience, Kwansei Gakuin University, 2-1 Gakuen, Sanda 669-1337, Japan.
authors.forename: Tetsuhiro
authors.initials: T
authors.lastname: Kikuchi
authors.affiliation: Department of Bioscience, Kwansei Gakuin University, 2-1 Gakuen, Sanda 669-1337, Japan.
authors.forename: Yukimasa
authors.initials: Y
authors.lastname: Shibata
authors.affiliation: Department of Bioscience, Kwansei Gakuin University, 2-1 Gakuen, Sanda 669-1337, Japan.
authors.forename: Hon-Song
authors.initials: HS
authors.lastname: Kim
authors.affiliation: Department of Bioscience, Kwansei Gakuin University, 2-1 Gakuen, Sanda 669-1337, Japan; Department of Developmental Biology and Neurosciences, Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan.
authors.forename: Yukihiko
authors.initials: Y
authors.lastname: Kubota
authors.affiliation: Department of Physiology, Tokyo Women's Medical University School of Medicine, Tokyo 162-8666, Japan.
authors.forename: Sawako
authors.initials: S
authors.lastname: Yoshina
authors.affiliation: Department of Physiology, Tokyo Women's Medical University School of Medicine, Tokyo 162-8666, Japan.
authors.forename: Shohei
authors.initials: S
authors.lastname: Mitani
authors.affiliation: Department of Bioscience, Kwansei Gakuin University, 2-1 Gakuen, Sanda 669-1337, Japan. Electronic address: nishiwaki@kwansei.ac.jp.
authors.forename: Kiyoji
authors.initials: K
authors.lastname: Nishiwaki
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D017173:Caenorhabditis elegans / Q000196:embryology*; D029742:Caenorhabditis elegans Proteins / Q000235:genetics / Q000378:metabolism*; D002465:Cell Movement / Q000235:genetics / Q000502:physiology*; D017931:DNA Primers / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D004847:Epithelial Cells / Q000502:physiology*; D006066:Gonads / Q000166:cytology / Q000196:embryology*; D007150:Immunohistochemistry; D008954:Models, Biological; D009154:Mutation / Q000235:genetics; D010957:Plasmids / Q000235:genetics; D034622:RNA Interference; D020744:rac GTP-Binding Proteins / Q000235:genetics
chemical_list: C407268:CED-10 protein, C elegans; D029742:Caenorhabditis elegans Proteins; D017931:DNA Primers; D004268:DNA-Binding Proteins; C000595689:MIG-39 protein, C elegans; C442327:Mig-2 protein, C elegans; D020744:rac GTP-Binding Proteins
keywords: BED-finger domain; Cell migration; Epithelial tube morphogenesis; Rac GTPase