title: pha-4, an HNF-3 homolog, specifies pharyngeal organ identity in Caenorhabditis elegans.
abstract: To build complex organs, embryos have evolved mechanisms that integrate the development of cells unrelated to one another by cell type or ancestry. Here we show that the pha-4 locus establishes organ identity for the Caenorhabditis elegans pharynx. In pha-4 mutants, pharyngeal cells are transformed into ectoderm. Conversely, ectopic pha-4 expression produces excess pharyngeal cells. pha-4 encodes an HNF-3 homolog selectively expressed in the nascent digestive tract, including all pharynx precursors at the time they are restricted to a pharyngeal fate. We suggest that pha-4 is a key component of a transcription-based mechanism to endow cells with pharyngeal organ identity.
authors.affiliation: Huntsman Cancer Institute, Center for Children, Department of Oncological Sciences, University of Utah, Salt Lake City, Utah 84112 USA.
authors.forename: M A
authors.initials: MA
authors.lastname: Horner
authors.forename: S
authors.initials: S
authors.lastname: Quintin
authors.forename: M E
authors.initials: ME
authors.lastname: Domeier
authors.forename: J
authors.initials: J
authors.lastname: Kimble
authors.forename: M
authors.initials: M
authors.lastname: Labouesse
authors.forename: S E
authors.initials: SE
authors.lastname: Mango
mesh_terms: D000818:Animals; D017173:Caenorhabditis elegans / Q000196:embryology* / Q000235:genetics*; D004268:DNA-Binding Proteins; D004064:Digestive System / Q000196:embryology; D051858:Forkhead Transcription Factors; D018507:Gene Expression Regulation, Developmental / Q000502:physiology; D017238:Genes, Helminth / Q000502:physiology; D009687:Nuclear Proteins / Q000235:genetics; D010614:Pharynx / Q000196:embryology*; D017386:Sequence Homology, Amino Acid; D015534:Trans-Activators / Q000235:genetics*; D014157:Transcription Factors / Q000235:genetics
chemical_list: D004268:DNA-Binding Proteins; C477894:FOXI1 protein, human; C106349:FOXJ1 protein, human; D051858:Forkhead Transcription Factors; D009687:Nuclear Proteins; D015534:Trans-Activators; D014157:Transcription Factors