ABSTRACT: Transcript profiling of Bln1 silenced plants (BSMV-VIGS) relative to empty vector and buffer treated controls in barley-powdery mildew interactions
Project description:Barley stripe mosaic virus-induced gene silencing (BSMV-VIGS) was used to identify significant new genes in the regulation of host innate immunity. This experiment was designed to uncover significant changes in Bln1 (Contig12219_at)-silenced plants relative to empty vector and buffer treated controls. Five independent biological replications of a split-plot experimental design were conducted with replications as blocks, treatment with Blumeria graminis f. sp. hordei (Bgh) as the whole-plot factor, and all combinations of genotype (Mla13 and Mla9) and VIGS treatment [Buffer control (mock), BSMV:00 (empty vector), and BSMV:Bln1248] as the split-plot factor for a total of 60 GeneChip hybridizations. Ten seedlings were used as a split-plot experimental unit for each combination of replication, Bgh treatment, genotype, and VIGS treatment. Plants were grown in a controlled 20°C glasshouse prior to VIGS treatment. Twelve days after VIGS treatment, half of the plants in each replication were challenged with the compatible Bgh isolate 5874. Top halves of 5 of the 10 seedling third leaves (about 10 cm) from each split-plot experimental unit were harvested into liquid N2 at 32 hours after inoculation (HAI) - the timepoint with the highest differential Bln1 transcript accumulation (Meng et al. 2009), and after initial establishment of the perihaustorial interface (Caldo et al. 2004). The remaining 5 leaves were used to record infection phenotype 7 days later. RNA was isolated for GeneChip hybridization from the 32-HAI samples. ****[PLEXdb(http://www.plexdb.org) has submitted this series at GEO on behalf of the original contributor, Yan Meng. The equivalent experiment is BB101 at PLEXdb.]
Project description:Blumeria graminis f.sp. hordei is an obligate biotrohic fungal pathogen causing powdery mildew in barley. As for other biotrophic fungi, haustorial structures are at the centre of the biotrophic interaction and molecular exchanges, delivering fungal effectors or virulence factors, and taking nutrient from the host. Haustoria are originiated by the fungus, following successful penetration of the initial penetration peg through the plant cell call. Haustorial structures mainly of fungal origin, but they are surrounding by a plant component, the extrauhaustorial membrane and matrix (EHM and EHMx) forming the extrahuastorial complex (EHMc). The plant protein make-up of the plant extrahaustorial components remained unexplored, and this is a first study trying to describe plant proteome associated with haustoria using samples enriched for these structures. Therefore, proteomes of haustoria enriched samples from the epidermis of barley leaves infected with Blumeria graminins f.sp. hordei, the causing agent of barley powdery mildew, were compared to infected epidermis and un-infected epidermis to identify haustoria associated plant proteins. Haustoria were enriched from infected epidermis by digesting epidermal cell walls with cell wall degrading enzymes prior to enrichment for haustorial structures. Proteins identified in these samples were compared to infected and uninfected epidermis samples using a non-targeted label free semi-quantitation method.
Project description:Virus Induced Gene Silencing (VIGS) was used to silence the expression of soybean Replication Protein 3 (GmRPA3). RNAseq was used to compare gene expression in GmRPA3 silenced and empty vector treated plants
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.
Project description:VIGS (virus-induced gene silencing) was used to silence a putative LRR-RLK, Affy ID Rbaal9i05_at, in barley. Expression patterns in leaves were compared between untreated control leaves, virus treated leaves, VIGS-Rbaal knockdown leaves and VIGS-Rbaal/PDS (phytoene desaturase) co-silenced leaves. ****[PLEXdb(http://www.plexdb.org) has submitted this series at GEO on behalf of the original contributor, David L Parrott. The equivalent experiment is BB108 at PLEXdb.] treatment: Untreated Control(3-replications); treatment: Empty Virus (no inserted plant sequences)(3-replications); treatment: Rbaal VIGS(3-replications); treatment: Co-silencing (Rbaal + PDS)(3-replications)
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