title: TaWRKY70 transcription factor in wheat QTL-2DL regulates downstream metabolite biosynthetic genes to resist Fusarium graminearum infection spread within spike.
abstract: A semi-comprehensive metabolomics was used to identify the candidate metabolites and genes to decipher mechanisms of resistance in wheat near-isogenic lines (NILs) containing QTL-2DL against Fusarium graminearum (Fg). Metabolites, with high fold-change in abundance, belonging to hydroxycinnamic acid amides (HCAAs): such as coumaroylagmatine, coumaroylputrescine and Fatty acids: phosphatidic acids (PAs) were identified as resistance related induced (RRI) metabolites in rachis of resistant NIL (NIL-R), inoculated with Fg. A WRKY like transcription factor (TF) was identified within the QTL-2DL region, along with three resistance genes that biosynthesized RRI metabolites. Sequencing and in-silico analysis of WRKY confirmed it to be wheat TaWRKY70. Quantitative real time-PCR studies showed a higher expression of TaWRKY70 in NIL-R as compared to NIL-S after Fg inoculation. Further, the functional validation of TaWRKY70 based on virus induced gene silencing (VIGS) in NIL-R, not only confirmed an increased fungal biomass but also decreased expressions of downstream resistance genes: TaACT, TaDGK and TaGLI1, along with decreased abundances of RRI metabolites biosynthesized by them. Among more than 200 FHB resistance QTL identified in wheat, this is the first QTL from which a TF was identified, and its downstream target genes as well as the FHB resistance functions were deciphered.
authors.affiliation: Plant Science Department, McGill University, 2111 Lakeshore road, Sainte Anne De Bellevue, Quebec, Canada H9X3V9.
authors.forename: Udaykumar
authors.initials: U
authors.lastname: Kage
authors.affiliation: Plant Science Department, McGill University, 2111 Lakeshore road, Sainte Anne De Bellevue, Quebec, Canada H9X3V9.
authors.forename: Kalenahalli N
authors.initials: KN
authors.lastname: Yogendra
authors.affiliation: Plant Science Department, McGill University, 2111 Lakeshore road, Sainte Anne De Bellevue, Quebec, Canada H9X3V9.
authors.forename: Ajjamada C
authors.initials: AC
authors.lastname: Kushalappa
mesh_terms: D018533:Biomass; D002853:Chromatography, Liquid; D002874:Chromosome Mapping; D060467:Disease Resistance / Q000235:genetics*; D005670:Fusarium; D055785:Gene Knockdown Techniques; D020868:Gene Silencing; D056726:Genetic Association Studies; D059014:High-Throughput Nucleotide Sequencing; D054884:Host-Pathogen Interactions / Q000235:genetics*; D013058:Mass Spectrometry; D053858:Metabolic Networks and Pathways / Q000235:genetics; D055442:Metabolome; D055432:Metabolomics; D010802:Phylogeny; D010935:Plant Diseases / Q000235:genetics / Q000382:microbiology; D011401:Promoter Regions, Genetic; D021381:Protein Transport; D040641:Quantitative Trait Loci; D019655:Quantitative Trait, Heritable; D014157:Transcription Factors / Q000378:metabolism*; D014908:Triticum / Q000382:microbiology* / Q000502:physiology*
chemical_list: D014157:Transcription Factors