title: Dolichol biosynthesis and its effects on the unfolded protein response and abiotic stress resistance in Arabidopsis.
abstract: Dolichols are long-chain unsaturated polyisoprenoids with multiple cellular functions, such as serving as lipid carriers of sugars used for protein glycosylation, which affects protein trafficking in the endoplasmic reticulum. The biological functions of dolichols in plants are largely unknown. We isolated an Arabidopsis thaliana mutant, lew1 (for leaf wilting1), that showed a leaf-wilting phenotype under normal growth conditions. LEW1 encoded a cis-prenyltransferase, which when expressed in Escherichia coli catalyzed the formation of dolichol with a chain length around C(80) in an in vitro assay. The lew1 mutation reduced the total plant content of main dolichols by approximately 85% and caused protein glycosylation defects. The mutation also impaired plasma membrane integrity, causing electrolyte leakage, lower turgor, reduced stomatal conductance, and increased drought resistance. Interestingly, drought stress in the lew1 mutant induced higher expression of the unfolded protein response pathway genes BINDING PROTEIN and BASIC DOMAIN/LEUCINE ZIPPER60 as well as earlier expression of the stress-responsive genes RD29A and COR47. The lew1 mutant was more sensitive to dark treatment, but this dark sensitivity was suppressed by drought treatment. Our data suggest that LEW1 catalyzes dolichol biosynthesis and that dolichol is important for plant responses to endoplasmic reticulum stress, drought, and dark-induced senescence in Arabidopsis.
authors.affiliation: State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
authors.forename: Hairong
authors.initials: H
authors.lastname: Zhang
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Ohyama
authors.forename: Julie
authors.initials: J
authors.lastname: Boudet
authors.forename: Zhizhong
authors.initials: Z
authors.lastname: Chen
authors.forename: Jilai
authors.initials: J
authors.lastname: Yang
authors.forename: Min
authors.initials: M
authors.lastname: Zhang
authors.forename: Toshiya
authors.initials: T
authors.lastname: Muranaka
authors.forename: Christophe
authors.initials: C
authors.lastname: Maurel
authors.forename: Jian-Kang
authors.initials: JK
authors.lastname: Zhu
authors.forename: Zhizhong
authors.initials: Z
authors.lastname: Gong
mesh_terms: D000222:Adaptation, Physiological; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D002462:Cell Membrane / Q000235:genetics / Q000378:metabolism; D002853:Chromatography, Liquid; D003624:Darkness; D004122:Dimethylallyltranstransferase / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D004286:Dolichols / Q000096:biosynthesis*; D055864:Droughts; D004591:Electrophoresis, Polyacrylamide Gel; D018506:Gene Expression Regulation, Plant; D005816:Genetic Complementation Test; D006031:Glycosylation; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D009154:Mutation; D010802:Phylogeny; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism; D017510:Protein Folding; D011499:Protein Processing, Post-Translational; D017386:Sequence Homology, Amino Acid; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D029681:Arabidopsis Proteins; D004286:Dolichols; D004122:Dimethylallyltranstransferase