Project description:Fusarium Head Blight (FHB) is a disease of wheat and other cereal crops, where, among other species, Fusarium graminearum infects the wheat inflorescence. Microarrays were used to observe differential gene expression in FHB-challenged spikes of the two European winter wheat genotypes Dream (moderately resistant) and Lynx (susceptible). Plants were either inoculated with the Fusarium graminearum strain IFA 65 (IFA Tulln) (500 macroconidia/floret) or were as control plants mock treated with desalted water. The inocula were injected into four spikelets at early anthesis and spikelets were later on collected at 32 and 72 h after inoculation. Four plants were sampled per genotype/treatment/sampling date. Total RNA was extracted from collected spikelets, and microarray analysis was performed using the Affymetrix Wheat GeneChip.
Project description:We performed ChIP-seq for the meiotic strand exchange protein DMC1, which marks an early stage in the meiotic recombination pathway, and the chromosome axis protein ASY1, which promotes interhomolog synapsis and recombination in plants, using tissue collected from immature pre-emergence spikes from wild type bread wheat cultivar Chinese Spring plants. To investigate connections between meiotic recombination and chromatin states in wheat, we also performed ChIP-seq for euchromatic (H3K4me3) and constitutive heterochromatic (H3K9me2 and H3K27me1) marks, and mapped genome-wide nucleosome occupancy via micrococcal nuclease sequencing (MNase-seq) using leaf tissue from Chinese Spring.
Project description:The economic importance of wheat and its contribution to human and livestock diets has been already demonstrated. However, wheat production is impacted by pests that induce yield reductions. Among these pests, wheat curl mite (WCM, Aceria tosichella Keifer) impacts wheat all around the world. WCM are tiny pests that feed within the whorl of developing leaves and prevent the leaves from unfurling by causing leaves curling. The curling of the leaves provides a protective niche for the WCM. Additionally, WCM are also the vector of serious viruses in wheat. Little is known regarding the impact of the WCM on wheat transcriptome, and to date, only one article has been published describing the wheat transcriptomic changes after 1 day of WCM feeding. To better understand the wheat transcriptome variation after long-term feeding by WCM (10 days post infestation (dpi)), we used an RNA-seq approach. We collected leaves uninfested and infested with WCR from two wheat cultivars: Byrd (WCM resistant) and Settler CL (WCM susceptible) at 10 dpi. Our transcriptomic analysis revealed the common and specific transcriptomic variations in WCM resistant and susceptible wheat cultivars, chromosome specific location of the differentially expressed genes, and also identified the gene functions and pathways involved in WCM resistance. Collectively, our study provides important insights on wheat defense mechanisms against WCM after long-term feeding.
Project description:Venn diagram showing overlap in binding sites. Genomic regions from MeDIP analysis (Late > Early) were compared for PARP1 ChIP-seq analysis (Early > Late) and TET1 ChIP-seq analysis (Early > Late). Numbers indicate the number of overlapping genes or regions.
Project description:RNA-seq of wheat lodicules in two higly-chasmogamous (HCH) (Piko and Poezja) and two low-chasmogamy (LCH) (Euforia and KWS Dacanto) varieties at two developmental stages - pre-flowering and early flowering.
Project description:TaGPC1 and TaGPC2 are NAC-domain transcription factors which accelerate the onset of senescence and facilitate nutrient translocation in wheat. We developed knockout mutants of these genes in tetraploid wheat and used RNA-seq to identify the effect of these mutations on the wheat flag leaf transcriptome during monocarpic senescence. Several transporter-related genes were identified which were upregulated during senescence and differentially expressed between genotypes. Illumina cDNA libraries were constructed from four biological replicates of three genotypes (WT, gpc-a1 and gpc-a1/gpc-b2) at three timepoints (Heading date, 12 days after anthesis and 22 days after anthesis). Reads were aligned to a collection of assembled genomic contigs from flow-sorted chromosome arms (A and B genomes only) provided by the International Wheat Genome Sequencing Consortium. A custom GTF file was generated to identify 139828 gene loci corresponding to transcribed regions of this reference sequence. Please note that the contig names provided by URGI (http://wheat-urgi.versailles.inra.fr/Seq-Repository) were used in the analysis. Most, but not all, of these loci are present in Ensembl (With a modified name, but the same basic information, chromosome arm and unique contig ID) at ftp://ftp.ensemblgenomes.org/pub/plants/release-22/fasta/triticum_aestivum/dna/ Therefore, the contig IDs from URGI (which are available for all our sequences) were used in the processed data file (i.e. the count table and GFF file) and an additional file describing the corresponding Ensembl names for these was provided (Additional_file_2.xlsx).
Project description:Leptosphaeria maculans, causal agent of stem canker disease, colonises oilseed rape (Brassica napus) in two stages: a short and early colonisation stage corresponding to cotyledon or leaf colonisation, and a late colonisation stage during which the fungus colonises systemically and symptomlessly the plant during several months before stem canker appears. To date, determinants of the late colonisation stage are poorly understood; L. maculans may either successfully escape plant defences leading to the stem canker development, or the plant can develop an “adult-stage” resistance reducing canker incidence. To get insight into these determinants, we performed an RNA-seq pilot project comparing fungal gene expression in infected cotyledons and in symptomless and necrotic stems. Despite the low fraction of fungal material in infected stems, enough fungal transcripts were detected and a large portion of fungal genes were expressed, thus validating the feasibility of the approach. Our analysis showed that all avirulence genes previously identified are under-expressed during stem colonisation compared to cotyledon colonisation. A validation RNA-seq experiment was then done to investigate the expression of candidate effector genes during systemic colonisation. 307 "late" effector candidates, under-expressed in the early colonisation stage and over-expressed in the infected stems, were identified. Finally our analysis revealed a link between regulation of expression of effectors and their genomic location: the late effector candidates, putatively involved in the systemic colonisation, are located in gene-rich genomic regions, whereas the "early" effector genes, over-expressed in the early colonisation stage, are located in gene-poor regions of the genome.