title: Mutations in the heatshock cognate 70 protein (hsc4) modulate Notch signaling.
abstract: In our effort to dissect the Notch signaling mechanism we have conducted a screen for mutations that reduce Notch signaling activity. We recovered nine complementation groups as modifiers of the hypomorphic Notch allele notchoid. Apart from the known Notch signaling modulators Notch, Delta and mastermind we isolated alleles in vestigial, wingless, scalloped and clipped, genes known to affect wing morphogenesis. In addition, we identified mutations in Bag, the gene encoding clathrin heavy chain and a dominant mutation of the cytosolic 70 kDa heatshock cognate protein encoded by the hsc4 gene, as Notch signaling modifier. We focused our attention on the latter mutation because it displays dramatic genetic interactions with mutations of the Notch receptor as well as several additional Notch signaling pathway elements. We discuss how hsc4, a gene thought to be involved in subcellular trafficking, may affect the number of functional Notch receptors on the cell surface.
authors.affiliation: Department of Biological Chemistry, UCLA School of Medicine, Los Angeles, CA/USA.
authors.forename: H K
authors.initials: HK
authors.lastname: Hing
authors.forename: L
authors.initials: L
authors.lastname: Bangalore
authors.forename: X
authors.initials: X
authors.lastname: Sun
authors.forename: S
authors.initials: S
authors.lastname: Artavanis-Tsakonas
mesh_terms: D000483:Alleles; D000818:Animals; D001483:Base Sequence; D002352:Carrier Proteins / Q000235:genetics*; D002874:Chromosome Mapping; D017931:DNA Primers / Q000235:genetics; D004330:Drosophila / Q000033:anatomy & histology / Q000235:genetics*; D029721:Drosophila Proteins; D005123:Eye / Q000033:anatomy & histology; D005260:Female; D017344:Genes, Insect; D005816:Genetic Complementation Test; D050883:HSC70 Heat-Shock Proteins; D018840:HSP70 Heat-Shock Proteins; D008297:Male; D008540:Meiosis / Q000235:genetics; D008565:Membrane Proteins / Q000235:genetics*; D009154:Mutation; D010641:Phenotype; D051880:Receptors, Notch; D015398:Signal Transduction; D014921:Wings, Animal / Q000033:anatomy & histology
chemical_list: D002352:Carrier Proteins; D017931:DNA Primers; D029721:Drosophila Proteins; D050883:HSC70 Heat-Shock Proteins; D018840:HSP70 Heat-Shock Proteins; D008565:Membrane Proteins; C497759:N protein, Drosophila; D051880:Receptors, Notch