title: The N-terminal and transmembrane domains of Commissureless are necessary for its function and trafficking within neurons.
abstract: Commissureless (Comm) is a novel transmembrane molecule necessary both for commissural axons to cross the midline of the Drosophila central nervous system and normal synaptogenesis. Comm is able to reduce cell surface levels of Roundabout (Robo), a receptor for the midline repellent Slit, on commissural axons and unknown inhibitors of synaptogenesis expressed on muscle cells. Comm is expressed dynamically and is found at the cell surface and within intracellular vesicles. Comm can bind Robo and when the proteins are co-expressed Robo is found co-localised with Comm intracellularly. Here we show that the ability of Comm to localise intracellularly and hence regulate Robo surface levels requires sequences in both the N-terminal and transmembrane domains. We also show that Comm can dimerise via its N-terminal domain. Furthermore, absence of the Comm N-terminal and transmembrane regions results in the protein being restricted to the neuron soma.
authors.affiliation: Molecular Neurobiology Group, MRC Centre for Developmental Neurobiology, New Hunt's House, Guy's Campus, King's College, London SE1 1UL, UK.
authors.forename: Marios
authors.initials: M
authors.lastname: Georgiou
authors.forename: Guy
authors.initials: G
authors.lastname: Tear
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D030801:Animals, Genetically Modified; D001369:Axons / Q000378:metabolism; D001483:Base Sequence; D018076:DNA, Complementary / Q000235:genetics; D004330:Drosophila / Q000196:embryology* / Q000235:genetics / Q000502:physiology*; D029721:Drosophila Proteins / Q000737:chemistry* / Q000235:genetics / Q000502:physiology*; D018507:Gene Expression Regulation, Developmental; D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D008565:Membrane Proteins / Q000737:chemistry* / Q000235:genetics / Q000502:physiology*; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009474:Neurons / Q000502:physiology*; D017434:Protein Structure, Tertiary; D011971:Receptors, Immunologic / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D000097905:Roundabout Proteins
chemical_list: D018076:DNA, Complementary; D029721:Drosophila Proteins; D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D011971:Receptors, Immunologic; D011993:Recombinant Fusion Proteins; D000097905:Roundabout Proteins; C110665:comm protein, Drosophila