Project description:We used two wheat genotypes, the susceptible wheat cultivar ‘8866 ’(S) and its near isogenic line with single powdery mildew resistance gene ‘pm30’ (R), to investigate gene expression changes in response to powdery mildew infection by using Wheat Genome Array
Project description:We used two wheat genotypes, the susceptible wheat cultivar ‘8866 ’(S) and its near isogenic line with single powdery mildew resistance gene ‘pm30’ (R), to investigate gene expression changes in response to powdery mildew infection by using Wheat Genome Array wheat young leveas of near isogenic lines before or 12 hours after powdery mildew infection were selected for RNA extraction and hybridization on Affymetrix microarrays.The leaf samples were harvested from three independent biological replicates, and the leaves without inoculation were regarded as control.
Project description:Powdery mildew caused by Erysiphe cruciferarum, is an epidemic of oil rapeseed (Brassica napus) growing worldwide, but resistant germplasm is rare in this species. We obtained the hybrid seeds of distant hybridization between powdery-mildew-immune Brassica carinata cultivar ‘White flower’ and susceptible B. napus cultivar ‘Zhongshuang11’. Five lines in the BC1F3 generation (F3 after backcross to 'Zhongshuang11') were identified to be resistant or moderately resistant. In order to identify the important biological responses to powdery mildew, the foliar transcriptomes of the resistant and susceptible plants in these progenies after powdery mildew inoculation were compared by using Illumina RNA-seq. We identified 10,454 differential expression genes (DEGs) and 1050 genes out of them are related to disease resistance. There were 271 DEGs in Group Resistance expressed at least two fold higher than in group S, while 779 DGEs expressed two fold lower. The genes highly expressed in Group Resistance are those encoding the proteins: (1) related to wax, chloroplast and cell wall metabolism, such as KCS6, CSP41B, RWA, callose synthetase 3, pectinase 9, fructosidase 2, 9s-lipoxygenase LOX2, etc.; (2) kinases including RKL, ERECTA, BAK1, BAM2, LysM receptor like kinase, and lipid transfer protein kinase ERl1 and ERl2; (3) broad spectrum powdery mildew resistance proteins RPW8, calmodulin MLO2, PMR5, MLP328, EDR2, RPS4 and RPS6, etc. In group susceptible, pectinesterase, cytochrome CYP81f2, LOX1, cysteine rich receptor protein kinases and serine / threonine protein kinases such as MEKK, RLK6, CRK45, APK1, BRl3, WAK1, WAK10, etc., and TIR-NB-LRR receptor like proteins R1M1, DSC1, DSC2 and pathogenesis-related protein PR-1 etc. were the most activated genes. The results provide the preliminarily knowledge about molecular mechanism in rapeseed defense response to powdery mildew.
Project description:It has been demonstrated that wheat overexpressing Pm3b, an allele of the R gene Pm3, has enhanced resistance against powdery mildew under field conditions. A gene expression profile study using GeneChip® Wheat Genome Array was performed to obtain insights into the mode of action of Pm3b and to elucidate the molecular basis of pleiotropic effects observed in three out of four independent transgenic events tested under field conditions. 24 samples were analyzed. Three biological replicates of each sample were included. Two independent transformation events and respective null segregants as control treated with fungicide or artificially inoculated with powdery mildew.
Project description:It has been demonstrated that wheat overexpressing Pm3b, an allele of the R gene Pm3, has enhanced resistance against powdery mildew under field conditions. A gene expression profile study using GeneChip® Wheat Genome Array was performed to obtain insights into the mode of action of Pm3b and to elucidate the molecular basis of pleiotropic effects observed in three out of four independent transgenic events tested under field conditions.
Project description:To test whether non-coding RNAs play roles in regulating response to powdery mildew infection and heat stress in wheat, by using Solexa high-throughput sequencing and computational analysis and experimental approach we cloned the small RNAs and identified 125 putative long npcRNAs from wheat leaves infected by preponderant physiological strain Erysiphe graminis f. sp. tritici (Egt) or by heat stress treatment. Among long non-coding RNAs, some were precursors of small RNAs such as microRNAs and siRNAs, two long npcRNAs were identified as signal recognition particle (SRP) 7S RNA variants, and three were characterized as U3 snoRNAs. Wheat long npcRNAs showed tissue dependent expression patterns and were responsive to powdery mildew infection and heat stress.
Project description:To identify genes involved in susceptibility, genechip hybridization experiments were performed in order to examine genes differentially expressed upon inoculation of resistant and susceptible wheat cultivars with powdery mildew. Some genes were identified which were just expressed in the susceptible host both after mock-inoculation and pathogen infection. Also, a total of 2693 transcripts were differentially expressed (fold change≥2) in Yumai 13 in response to powdery mildew as compared to itself, comprising 1464 and 1229 up- and down-regulated genes respectively.
Project description:The receptor kinase FERONIA (FER) is a susceptibility factor for biotrophic powdery mildew fungal pathogens in Arabidopsis thaliana, but the underlying molecular mechanisms remain largely unknown. FER is required for the perception of endogenous RAPID ALKALINIZATION FACTOR (RALF) peptides to control various aspects of plant growth, development and immunity. RALFs are either perceived by FER/LORELEI-LIKE GPI-ANCHORED PROTEIN (LLG) heterocomplexes to induce cellular responses or bind to LEUCINE-RICH REPEAT EXTENSIN (LRX) proteins as cell wall structural components. Combining genetics, cell biology and biochemistry, we found that FER`s endogenous RALF ligands are necessary for full colonization success of the powdery mildew species Erysiphe cruciferarum. We reveal that LLGs and LRXs are also powdery mildew susceptibility factors. We show that cell wall remodeling and apoplastic pH homeostasis, hallmark features of RALF function, support powdery mildew reproductive success. We provide data that RALF-dependent powdery mildew pathogenesis is partially independent of FER. Powdery mildew fungi likely do not produce RALF peptide mimics, suggesting their reliance on endogenous RALFs for successful host colonization. We propose that powdery mildew fungi require RALF-mediated modulation of apoplastic pH and pectin re-modelling for successful host colonization, highlighting a new susceptibility mechanism by obligate biotrophic fungi.