title: Yeast functional analysis: identification of two essential genes involved in ER to Golgi trafficking.
abstract: We screened for genes potentially involved in the secretory and vacuolar pathways a collection of 61 yeast strains, each bearing an essential orphan gene regulated by the tetO7-CYC1 promoter that can be down-regulated by doxycycline. After down-regulating the expression of these genes, we performed systematic Western blot analysis for markers of the secretory and vacuolar pathways that undergo post-translational modifications in their intracellular trafficking. Accumulation of protein precursors, revealed by Western immunoblot analysis, indicates defects in the secretory pathway or in associated biochemical modifications. After screening the whole collection, we identified two genes involved in ER to Golgi trafficking: RER2, a cis-prenyl transferase, and USE1, the function of which was unknown. We demonstrated that repression of USE1 also leads to BiP secretion, and therefore likely affects retrograde, in addition to anterograde, ER to Golgi trafficking. The collection also includes two essential genes involved in intracellular trafficking that were conveniently repressed without resulting growth or trafficking defects.
authors.affiliation: Institut Jacques Monod, CNRS UMR7592, Universités Paris VI et VII, 2 place Jussieu, 75251 Paris Cedex 05, France.
authors.forename: Naïma
authors.initials: N
authors.lastname: Belgareh-Touzé
authors.forename: Marisol
authors.initials: M
authors.lastname: Corral-Debrinski
authors.forename: Heike
authors.initials: H
authors.lastname: Launhardt
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Galan
authors.forename: Thomas
authors.initials: T
authors.lastname: Munder
authors.forename: Sophie
authors.initials: S
authors.lastname: Le Panse
authors.forename: Rosine
authors.initials: R
authors.lastname: Haguenauer-Tsapis
mesh_terms: D001692:Biological Transport; D004122:Dimethylallyltranstransferase / Q000235:genetics / Q000502:physiology*; D015536:Down-Regulation; D004721:Endoplasmic Reticulum / Q000378:metabolism* / Q000648:ultrastructure; D005800:Genes, Fungal; D006056:Golgi Apparatus / Q000378:metabolism*; D008565:Membrane Proteins / Q000235:genetics / Q000502:physiology*; D050767:Qc-SNARE Proteins; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000502:physiology*; D014166:Transferases / Q000235:genetics / Q000502:physiology*
chemical_list: D008565:Membrane Proteins; D050767:Qc-SNARE Proteins; D029701:Saccharomyces cerevisiae Proteins; C477343:Use1 protein, S cerevisiae; D014166:Transferases; C106821:cis-prenyl transferase; D004122:Dimethylallyltranstransferase; C485360:RER2 protein, S cerevisiae