Publications by authors named "Therese Ouellet"

Deoxynivalenol (DON) is a prominent mycotoxin showing significant accumulation in cereal plants during infection by the phytopathogen . It is a virulence factor that is important in the spread of within cereal heads, and it causes serious yield losses and significant contamination of cereal grains. In recent decades, genetic and genomic studies have facilitated the characterization of the molecular pathways of DON biosynthesis in and the environmental factors that influence DON accumulation.

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In differential gene expression data analysis, one objective is to identify groups of co-expressed genes from a large dataset in order to detect the association between such a group of genes and an experimental condition. This is often done through a clustering approach, such as k-means or bipartition hierarchical clustering, based on particular similarity measures in the grouping process. In such a dataset, the gene differential expression itself is an innate attribute that can be used in the feature extraction process.

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In RNA-seq data processing, short reads are usually aligned from one species against its own genome sequence; however, in plant-pathogen interaction systems, reads from both host and pathogen samples are blended together. In contrast with single-genome analyses, both pathogen and host reference genomes are involved in the alignment process. In such circumstances, the order in which the alignment is carried out, whether the host or pathogen is aligned first, or if both genomes are aligned simultaneously, influences the read counts of certain genes.

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RNA/DNA difference (RDD) is a post-transcriptional modification playing a crucial role in regulating diverse biological processes in eukaryotes. Although it has been extensively studied in plant chloroplast and mitochondria genomes, RDDs in plant nuclear genomes are not well studied at present. Here, we investigated the RDDs associated with fusarium head blight (FHB) through a novel method by comparing the RNA-seq data between Fusarium-infected and control samples of four wheat genotypes.

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Background: The tall wheatgrass species Thinopyrum elongatum carries a strong fusarium head blight (FHB) resistance locus located on the long arm of chromosome 7 (7EL) as well as resistance to leaf and stem rusts, all diseases with a significant impact on wheat production. Towards understanding the contribution of Th. elongatum 7EL to improvement of disease resistance in wheat, the genomic sequence of the 7EL fragment present in the wheat Chinese Spring (CS) telosomic addition line CS-7EL was determined and the contribution and impact of 7EL on the rachis transcriptome during FHB infection was compared between CS and CS-7EL.

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The English grain aphid and phytopathogen are wheat spike colonizers. "Synergistic" effects of the coexistence of and on the wheat spikes have been shown in agroecosystems. To develop genetic resistance in diverse wheat cultivars, an important question is how to discover wheat- interactions under influence.

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The tall wheatgrass species carries on the long arm of chromosome 7E, a locus that contributes strongly to resistance to fusarium head blight (FHB), a devastating fungal disease affecting wheat crops in all temperate areas of the world. Introgression of 7E chromatin into chromosome 7D of wheat was induced by the mutant of CS. Recombinants between chromosome 7E and wheat chromosome 7D, induced by the mutation, were monitored by a combination of molecular markers and phenotyping for FHB resistance.

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The diploid form of tall wheatgrass, (Host) D.R. Dewey (2 = 2 = 14, EE genome), has a high level of resistance to fusarium head blight.

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Background: Fusarium head blight (FHB) is a major disease of cereal crops, caused by the fungal pathogen Fusarium graminearum and related species. Breeding wheat for FHB resistance contributes to increase yields and grain quality and to reduce the use of fungicides. The identification of genes and markers for FHB resistance in different wheat genotypes has nevertheless proven challenging.

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Deoxynivalenol (DON) is a mycotoxin virulence factor that promotes growth of the fungus in wheat floral tissues. To further our understanding of the effects of DON exposure on plant cell function, we characterized DON-induced transcriptional changes in wheat spikelets. Four hundred wheat genes were differentially expressed during infection with wild-type as compared with a mutant strain that is unable to produce DON.

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Background: Targeted genome editing using the Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/Cas9 system has been applied in a large number of plant species. Using a gene-specific single guide RNA (sgRNA) and the CRISPR/Cas9 system, small editing events such as deletions of few bases can be obtained. However larger deletions are required for some applications.

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Following publication of the original article [1], we have been notified that some important information was omitted by the authors in the Copyright note. The Copyright note should read as below.

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Background: Fusarium head blight (FHB) is a problem of great concern in small grain cereals, especially wheat. A quantitative trait locus (QTL) for FHB resistance (FHB_SFI) located on the long arm of chromosome 2D in the spring wheat genotype Wuhan 1 is a resistance locus which has potential to improve the FHB resistance of bread wheat since it confers effective resistance to wheat breeding lines. Recently, differentially expressed genes (DEG) have been identified by comparing near isogenic lines (NIL) carrying the susceptible and resistant alleles for the 2DL QTL, using RNA-Seq.

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Background: Phytohormones are key regulators of plant growth, development, and signalling networks involved in responses to diverse biotic and abiotic stresses. Transcriptional reference maps of hormone responses have been reported for several model plant species such as Arabidopsis thaliana, Oryza sativa, and Brachypodium distachyon. However, because of species differences and the complexity of the wheat genome, these transcriptome data are not appropriate reference material for wheat studies.

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Fusarium head blight (FHB) is a major cereal crop disease, caused most frequently by the fungus Fusarium graminearum. We have previously demonstrated that F. graminearum can utilize SA as sole source of carbon to grow.

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Fusarium head blight (FHB or scab) caused by Fusarium spp. is a destructive disease of wheat. Since the most effective sources of FHB resistance are typically associated with unfavorable agronomic traits, breeding commercial cultivars that combine desired agronomic traits and a high level of FHB resistance remains a considerable challenge.

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Background: Fusarium head blight (FHB) of wheat in North America is caused mostly by the fungal pathogen Fusarium graminearum (Fg). Upon exposure to Fg, wheat initiates a series of cellular responses involving massive transcriptional reprogramming. In this study, we analyzed transcriptomics data of four wheat genotypes (Nyubai, Wuhan 1, HC374, and Shaw), at 2 and 4 days post inoculation (dpi) with Fg, using RNA-seq technology.

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Fusarium head blight (FHB), caused by the fungus , represents one of the major wheat diseases worldwide, determining severe yield losses and reduction of grain quality due to the accumulation of mycotoxins. The molecular response associated with the wheat 2DL FHB resistance QTL was mined through a comprehensive transcriptomic analysis of the early response to infection, at 3 days post-inoculation, in spikelets and rachis. The analyses were conducted on two near isogenic lines (NILs) differing for the presence of the 2DL QTL (2-2618, resistant 2DL+ and 2-2890, susceptible null).

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Fusarium graminearum is a plant pathogen that can cause the devastating cereal grain disease fusarium head blight in temperate regions of the world. Previous studies have shown that F. graminearum can synthetize indole-3-acetic acid (auxin) using l-tryptophan (L-TRP)-dependent pathways.

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Fusarium graminearum is a devastating pathogenic fungus causing fusarium head blight (FHB) of wheat. This fungus can produce indole-3-acetic acid (IAA) and a very large amount of IAA accumulates in wheat head tissues during the first few days of infection by F. graminearum.

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Fusarium graminearum is a broad host pathogen threatening cereal crops in temperate regions around the world. To better understand how F. graminearum adapts to different hosts, we have performed a comparison of the transcriptome of a single strain of F.

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The English grain aphid, Sitobion avenae (F.) (Hemiptera: Aphididae), is a common worldwide pest of wheat (Triticum aestivum L.).

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TRI6 is a positive regulator of the trichothecene gene cluster and the production of trichothecene mycotoxins [deoxynivalenol (DON)] and acetylated forms such as 15-Acetyl-DON) in the cereal pathogen Fusarium graminearum. As a global transcriptional regulator, TRI6 expression is modulated by nitrogen-limiting conditions, sources of nitrogen and carbon, pH and light. However, the mechanism by which these diverse environmental factors affect TRI6 expression remains underexplored.

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The search for fast and reliable methods allowing for extraction of biomarker genes, e.g. responsible for a plant resistance to a certain pathogen, is one of the most important and highly exploited data mining problem in bioinformatics.

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