title: The 9-lipoxygenase GhLOX1 gene is associated with the hypersensitive reaction of cotton Gossypium hirsutum to Xanthomonas campestris pv malvacearum.
abstract: Hypersensitive reaction (HR) cell death of cotton to the incompatible race 18 from Xanthomonas campestris pathovar malvacearum (Xcm) is associated with 9S-lipoxygenase activity (LOX) responsible for lipid peroxidation. Here, we report the cloning of cotton (Gossypium hirsutum L.) LOX gene (GhLOX1) and the sequencing of its promoter. GhLOX1 was found to be highly expressed during Xcm induced HR. Sequence analysis showed that GhLOX1 is a putative 9-LOX, and GhLOX1 promoter contains SA and JA responsive elements. Investigation on LOX signalisation on cotyledons infiltrated with salicylic acid (SA), or incubated with methyl-jasmonate (MeJA) revealed that both treatments induced LOX activity and GhLOX1 gene expression. HR-like symptoms were observed when LOX substrates were then injected in treated (MeJA and SA) cotyledons or when Xcm compatible race 20 was inoculated on MeJA treated cotyledons. Together these results support the fact that GhLOX1 encodes a 9 LOX whose activity would be involved in cell death during cotton HR.
authors.affiliation: IRD, UMR RPB Résistance des Plantes aux Bioagresseurs, 911 Avenue Agropolis, B.P. 64501, 34394 Montpellier cedex 5, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Marmey
authors.forename: Aïda
authors.initials: A
authors.lastname: Jalloul
authors.forename: Majd
authors.initials: M
authors.lastname: Alhamdia
authors.forename: Komi
authors.initials: K
authors.lastname: Assigbetse
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Cacas
authors.forename: Andreas E
authors.initials: AE
authors.lastname: Voloudakis
authors.forename: Antony
authors.initials: A
authors.lastname: Champion
authors.forename: Alain
authors.initials: A
authors.lastname: Clerivet
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Montillet
authors.forename: Michel
authors.initials: M
authors.lastname: Nicole
mesh_terms: D000085:Acetates / Q000378:metabolism; D000595:Amino Acid Sequence; D001483:Base Sequence; D018548:Cotyledon / Q000378:metabolism; D003517:Cyclopentanes / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D003368:Gossypium / Q000235:genetics* / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000737:chemistry; D008084:Lipoxygenase / Q000235:genetics* / Q000378:metabolism / Q000502:physiology*; D008969:Molecular Sequence Data; D054883:Oxylipins / Q000378:metabolism; D010802:Phylogeny; D018515:Plant Leaves / Q000378:metabolism; D011401:Promoter Regions, Genetic; D020156:Salicylic Acid / Q000494:pharmacology; D017386:Sequence Homology, Amino Acid; D014974:Xanthomonas / Q000378:metabolism*
chemical_list: D000085:Acetates; D003517:Cyclopentanes; D054883:Oxylipins; C072239:methyl jasmonate; D006861:Hydrogen Peroxide; D008084:Lipoxygenase; D020156:Salicylic Acid