title: Facilitation of Fusarium graminearum Infection by 9-Lipoxygenases in Arabidopsis and Wheat.
abstract: Fusarium graminearum causes Fusarium head blight, an important disease of wheat. F. graminearum can also cause disease in Arabidopsis thaliana. Here, we show that the Arabidopsis LOX1 and LOX5 genes, which encode 9-lipoxygenases (9-LOXs), are targeted during this interaction to facilitate infection. LOX1 and LOX5 expression were upregulated in F. graminearum-inoculated plants and loss of LOX1 or LOX5 function resulted in enhanced disease resistance in the corresponding mutant plants. The enhanced resistance to F. graminearum infection in the lox1 and lox5 mutants was accompanied by more robust induction of salicylic acid (SA) accumulation and signaling and attenuation of jasmonic acid (JA) signaling in response to infection. The lox1- and lox5-conferred resistance was diminished in plants expressing the SA-degrading salicylate hydroxylase or by the application of methyl-JA. Results presented here suggest that plant 9-LOXs are engaged during infection to control the balance between SA and JA signaling to facilitate infection. Furthermore, since silencing of TaLpx-1 encoding a 9-LOX with homology to LOX1 and LOX5, resulted in enhanced resistance against F. graminearum in wheat, we suggest that 9-LOXs have a conserved role as susceptibility factors in disease caused by this important fungus in Arabidopsis and wheat.
authors.affiliation: 1 Department of Biological Sciences, University of North Texas, Denton, TX 76203, U.S.A.;|2 Department of Biology, Indiana University-Purdue University, Fort Wayne, IN 46805, U.S.A.;
authors.forename: Vamsi J
authors.initials: VJ
authors.lastname: Nalam
authors.affiliation: 1 Department of Biological Sciences, University of North Texas, Denton, TX 76203, U.S.A.;
authors.forename: Syeda
authors.initials: S
authors.lastname: Alam
authors.affiliation: 1 Department of Biological Sciences, University of North Texas, Denton, TX 76203, U.S.A.;
authors.forename: Jantana
authors.initials: J
authors.lastname: Keereetaweep
authors.affiliation: 1 Department of Biological Sciences, University of North Texas, Denton, TX 76203, U.S.A.;
authors.forename: Barney
authors.initials: B
authors.lastname: Venables
authors.affiliation: 3 Department of Plant Pathology, Kansas State University, Manhattan, KS 66506, U.S.A.;
authors.forename: Dehlia
authors.initials: D
authors.lastname: Burdan
authors.affiliation: 3 Department of Plant Pathology, Kansas State University, Manhattan, KS 66506, U.S.A.;
authors.forename: Hyeonju
authors.initials: H
authors.lastname: Lee
authors.affiliation: 3 Department of Plant Pathology, Kansas State University, Manhattan, KS 66506, U.S.A.;
authors.forename: Harold N
authors.initials: HN
authors.lastname: Trick
authors.affiliation: 1 Department of Biological Sciences, University of North Texas, Denton, TX 76203, U.S.A.;
authors.forename: Sujon
authors.initials: S
authors.lastname: Sarowar
authors.affiliation: 1 Department of Biological Sciences, University of North Texas, Denton, TX 76203, U.S.A.;|4 Department of Plant Sciences, University of Hyderabad, Gachibowli, Hyderabad, India.
authors.forename: Ragiba
authors.initials: R
authors.lastname: Makandar
authors.affiliation: 1 Department of Biological Sciences, University of North Texas, Denton, TX 76203, U.S.A.;
authors.forename: Jyoti
authors.initials: J
authors.lastname: Shah
mesh_terms: D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics / Q000276:immunology / Q000382:microbiology; D001483:Base Sequence; D003517:Cyclopentanes / Q000378:metabolism; D060467:Disease Resistance; D005670:Fusarium / Q000502:physiology*; D055785:Gene Knockdown Techniques; D017930:Genes, Reporter; D058945:Lipoxygenases / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation; D054883:Oxylipins / Q000378:metabolism; D010935:Plant Diseases / Q000276:immunology* / Q000382:microbiology; D010937:Plant Growth Regulators / Q000378:metabolism; D018515:Plant Leaves / Q000382:microbiology; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D030821:Plants, Genetically Modified; D020156:Salicylic Acid / Q000378:metabolism; D017422:Sequence Analysis, DNA; D015398:Signal Transduction; D014908:Triticum / Q000201:enzymology* / Q000235:genetics / Q000276:immunology / Q000382:microbiology
chemical_list: D003517:Cyclopentanes; D054883:Oxylipins; D010937:Plant Growth Regulators; D010940:Plant Proteins; C011006:jasmonic acid; D058945:Lipoxygenases; D020156:Salicylic Acid