title: The Bro1-domain protein, EGO-2, promotes Notch signaling in Caenorhabditis elegans.
abstract: In Caenorhabditis elegans, as in other animals, Notch-type signaling mediates numerous inductive events during development. The mechanism of Notch-type signaling involves proteolytic cleavage of the receptor and subsequent transport of the receptor intracellular domain to the nucleus, where it acts as a transcriptional regulator. Notch-type signaling activity is modulated by post-translational modifications and endocytosis of ligand and receptor. We previously identified the ego-2 (enhancer of glp-1) gene as a positive regulator of germline proliferation that interacts genetically with the GLP-1/Notch signaling pathway in the germline. Here, we show that ego-2 positively regulates signaling in various tissues via both GLP-1 and the second C. elegans Notch-type receptor, LIN-12. ego-2 activity also promotes aspects of development not known to require GLP-1 or LIN-12. The EGO-2 protein contains a Bro1 domain, which is known in other systems to localize to certain endosomal compartments. EGO-2 activity in the soma promotes GLP-1 signaling in the germline, consistent with a role for EGO-2 in production of active ligand. Another C. elegans Bro1-domain protein, ALX-1, is known to interact physically with LIN-12/Notch. We document a complex phenotypic interaction between ego-2 and alx-1, consistent with their relationship being antagonistic with respect to some developmental processes and agonistic with respect to others.
authors.affiliation: Department of Biology, Syracuse University, 108 College Place, Syracuse, NY 13244, USA.
authors.forename: Ying
authors.initials: Y
authors.lastname: Liu
authors.forename: Eleanor M
authors.initials: EM
authors.lastname: Maine
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D030801:Animals, Genetically Modified; D001483:Base Sequence; D017173:Caenorhabditis elegans / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029742:Caenorhabditis elegans Proteins / Q000235:genetics / Q000378:metabolism*; D002874:Chromosome Mapping; D018509:DNA, Helminth / Q000235:genetics; D004705:Endocytosis; D005260:Female; D017238:Genes, Helminth; D005854:Germ Cells; D008297:Male; D008540:Meiosis / Q000235:genetics / Q000502:physiology; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide; D034622:RNA Interference; D051880:Receptors, Notch / Q000235:genetics / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction; D013091:Spermatogenesis / Q000235:genetics / Q000502:physiology
chemical_list: D029742:Caenorhabditis elegans Proteins; D018509:DNA, Helminth; C060620:Glp-1 protein, C elegans; C082460:Lin-12 protein, C elegans; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D051880:Receptors, Notch; C086488:lag-2 protein, C elegans