LIN-39/Hox triggers cell division and represses EFF-1/fusogen-dependent vulval cell fusion.
General mechanisms by which Hox genes establish cell fates are known. However, a few Hox effectors mediating cell behaviors have been identified. Here we found the first effector of LIN-39/HoxD4/Dfd in Caenorhabditis elegans. In specific vulval precursor cells (VPCs), LIN-39 represses early and late expression of EFF-1, a membrane protein essential for cell fusion. Repression of eff-1 is also achieved by the activity of CEH-20/Exd/Pbx, a known cofactor of Hox proteins. Unfused VPCs in lin-39(-);eff-1(-) double mutants fail to divide but migrate, executing vulval fates. Thus, lin-39 is essential for inhibition of EFF-1-dependent cell fusion and stimulation of cell proliferation during vulva formation. Supplemental material is available at http://www.genesdev.org.
Shemer
Gidi
G
Department of Biology, Technion-Israel Institute of Technology, Haifa, 32000, Israel.
Podbilewicz
Benjamin
B
D000818:Animals; D030801:Animals, Genetically Modified; D001665:Binding Sites; D017173:Caenorhabditis elegans / Q000166:cytology*; D029742:Caenorhabditis elegans Proteins / Q000502:physiology*; D002454:Cell Differentiation; D002455:Cell Division; D002459:Cell Fusion; D004627:Embryonic Induction; D005260:Female; D005455:Fluorescent Antibody Technique; D018507:Gene Expression Regulation, Developmental; D015801:Helminth Proteins / Q000378:metabolism; D018398:Homeodomain Proteins / Q000502:physiology*; D006720:Homozygote; D008565:Membrane Proteins / Q000502:physiology*; D008958:Models, Molecular; D009154:Mutation; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D013234:Stem Cells / Q000378:metabolism; D014157:Transcription Factors; D014844:Vulva / Q000166:cytology*
D029742:Caenorhabditis elegans Proteins; D015801:Helminth Proteins; D018398:Homeodomain Proteins; D008565:Membrane Proteins; D011994:Recombinant Proteins; D014157:Transcription Factors; C418523:ceh-20 protein, C elegans; C108673:lin-39 protein, C elegans