title: Kes1p shares homology with human oxysterol binding protein and participates in a novel regulatory pathway for yeast Golgi-derived transport vesicle biogenesis.
abstract: The yeast phosphatidylinositol transfer protein (Sec14p) is required for biogenesis of Golgi-derived transport vesicles and cell viability, and this essential Sec14p requirement is abrogated by inactivation of the CDP-choline pathway for phosphatidylcholine biosynthesis. These findings indicate that Sec14p functions to alleviate a CDP-choline pathway-mediated toxicity to yeast Golgi secretory function. We now report that this toxicity is manifested through the action of yeast Kes1p, a polypeptide that shares homology with the ligand-binding domain of human oxysterol binding protein (OSBP). Identification of Kes1p as a negative effector for Golgi function provides the first direct insight into the biological role of any member of the OSBP family, and describes a novel pathway for the regulation of Golgi-derived transport vesicle biogenesis.
authors.affiliation: Department of Cell Biology, University of Alabama at Birmingham, 35294-0005, USA.
authors.forename: M
authors.initials: M
authors.lastname: Fang
authors.forename: B G
authors.initials: BG
authors.lastname: Kearns
authors.forename: A
authors.initials: A
authors.lastname: Gedvilaite
authors.forename: S
authors.initials: S
authors.lastname: Kagiwada
authors.forename: M
authors.initials: M
authors.lastname: Kearns
authors.forename: M K
authors.initials: MK
authors.lastname: Fung
authors.forename: V A
authors.initials: VA
authors.lastname: Bankaitis
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D001483:Base Sequence; D001665:Binding Sites; D002352:Carrier Proteins / Q000378:metabolism; D003566:Cytidine Diphosphate Choline / Q000378:metabolism; D017931:DNA Primers; D005656:Fungal Proteins / Q000737:chemistry / Q000378:metabolism*; D006056:Golgi Apparatus / Q000502:physiology* / Q000648:ultrastructure; D006801:Humans; D008565:Membrane Proteins; D010716:Phosphatidylinositols / Q000378:metabolism; D049294:Phospholipid Transfer Proteins; D016133:Polymerase Chain Reaction; D011987:Receptors, Steroid / Q000737:chemistry*; D011994:Recombinant Proteins / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000502:physiology* / Q000648:ultrastructure*; D029701:Saccharomyces cerevisiae Proteins; D017386:Sequence Homology, Amino Acid; D000098825:Oxysterol Binding Proteins
chemical_list: D002352:Carrier Proteins; D017931:DNA Primers; D005656:Fungal Proteins; C087901:KES1 protein, S cerevisiae; D008565:Membrane Proteins; D010716:Phosphatidylinositols; D049294:Phospholipid Transfer Proteins; D011987:Receptors, Steroid; D011994:Recombinant Proteins; C118289:SEC24 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D000098825:Oxysterol Binding Proteins; D003566:Cytidine Diphosphate Choline