title: The Arabidopsis COW1 gene encodes a phosphatidylinositol transfer protein essential for root hair tip growth.
abstract: Root hairs are a major site for the uptake of water and nutrients into plants, and they form an increasingly important model system for the study of development in higher plants. We now report on the molecular genetic analysis of the srh1 mutant in Arabidopsis thaliana impaired in root hair tip growth. We show that srh1 is a new allele of cow1 (can of worms1) and we identified the COW1 gene using a positional cloning strategy. The N-terminus of the COW1 protein is 32% identical to an essential phosphatidylinositol transfer protein (PITP), the yeast Sec14 protein (sec14p) while the C-terminus is 34.5% identical to a late nodulin of Lotus japonicus, Nlj16. We show that expression of the COW1 lipid-binding domain complements the growth defect associated with Sec14p dysfunction in yeast. In addition, we show that GFP fused to the COW1 protein specifically accumulates at the site of root hair outgrowth. We conclude that the COW1 protein is a PITP, essential for proper root hair growth.
authors.affiliation: Station de Génétique et d'Amélioration des Plantes, INRA, Route de St Cyr, 78026 Versailles, France.
authors.forename: Karen
authors.initials: K
authors.lastname: Böhme
authors.forename: Yong
authors.initials: Y
authors.lastname: Li
authors.forename: Florence
authors.initials: F
authors.lastname: Charlot
authors.forename: Claire
authors.initials: C
authors.lastname: Grierson
authors.forename: Katia
authors.initials: K
authors.lastname: Marrocco
authors.forename: Kyotaka
authors.initials: K
authors.lastname: Okada
authors.forename: Michel
authors.initials: M
authors.lastname: Laloue
authors.forename: Fabien
authors.initials: F
authors.lastname: Nogué
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D008969:Molecular Sequence Data; D009154:Mutation; D010641:Phenotype; D049294:Phospholipid Transfer Proteins / Q000096:biosynthesis* / Q000235:genetics*; D018517:Plant Roots / Q000235:genetics / Q000254:growth & development*; D030821:Plants, Genetically Modified; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
chemical_list: D049294:Phospholipid Transfer Proteins