title: The roles of two C. elegans HOX co-factor orthologs in cell migration and vulva development.
abstract: Anteroposterior cell migration and patterning in C. elegans are governed by multiple, interacting signaling pathways and transcription factors. In this study, we have investigated the role of ceh-20, the C. elegans ortholog of the HOX co-factor Extradenticle (Exd/Pbx), and unc-62, the C. elegans ortholog of Homothorax (Hth/Meis/Prep), in two processes that are regulated by Hox gene lin-39: cell migration and vulva formation. As in lin-39 mutants, the anterior migrations of neuroblasts in the Q lineage are truncated in Hox co-factor mutants. Surprisingly, though, our findings suggested that the roles of ceh-20 and unc-62 are different from that of lin-39; specifically, ceh-20 and unc-62 but not lin-39 are required for the transmembrane protein MIG-13 to promote anterior migration. To our knowledge, ceh-20 and unc-62 are the only genes that have been implicated in the mig-13 pathway. We find that ceh-20 and unc-62 are also required for several steps in vulva development. Surprisingly, ceh-20 and unc-62 mutants have phenotypes that are starkly different from those of lin-39 mutants. Thus, in this process, too, ceh-20 and unc-62 are likely to have functions that are independent of lin-39.
authors.affiliation: Department of Biochemistry and Biophysics, University of California, San Francisco, Mission Bay Genentech Hall, 600 16th Street, Room S312A, San Francisco, CA 94143-2200, USA.
authors.forename: Lucie
authors.initials: L
authors.lastname: Yang
authors.forename: Mary
authors.initials: M
authors.lastname: Sym
authors.forename: Cynthia
authors.initials: C
authors.lastname: Kenyon
mesh_terms: D000818:Animals; D017173:Caenorhabditis elegans / Q000196:embryology*; D029742:Caenorhabditis elegans Proteins / Q000235:genetics* / Q000378:metabolism; D002465:Cell Movement / Q000235:genetics / Q000502:physiology*; D005260:Female; D018398:Homeodomain Proteins / Q000235:genetics* / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D014844:Vulva / Q000196:embryology*
chemical_list: D029742:Caenorhabditis elegans Proteins; D018398:Homeodomain Proteins; C081538:Mab-5 protein, C elegans; D014157:Transcription Factors; C109537:Unc-62 protein, C elegans; C418523:ceh-20 protein, C elegans; C108673:lin-39 protein, C elegans