Publications by authors named "Veronique Brunaud"

Monoterpene indole alkaloids (MIAs) are valuable metabolites produced in numerous medicinal plants from the Apocynaceae family such as Alstonia scholaris, which synthesizes strictamine, a MIA displaying neuropharmacological properties of a potential importance. To get insights into the MIA metabolism in A. scholaris, we studied here both the spatial and transcriptional regulations of MIA genes by performing a robust transcriptomics analysis of the main plant organs, leaf epidermis but also by sequencing RNA from leaves transiently overexpressing the master transcriptional regulator MYC2.

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  • Black poplar (Populus nigra L.) is an ecologically significant tree species found in Eurasian riparian ecosystems and is often used to create cultivated hybrids.
  • This research involved analyzing transcriptomic data from 241 individuals of P. nigra, collected from various river catchments across Europe, to identify genetic variants for future studies.
  • The study produced over 878,000 biallelic polymorphisms, with data available for public access, facilitating research on population genomics and the genetic structure of this species.
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Plant mitochondria represent the largest group of respiring organelles on the planet. Plant mitochondrial messenger RNAs (mRNAs) lack Shine-Dalgarno-like ribosome-binding sites, so it is unknown how plant mitoribosomes recognize mRNA. We show that "mitochondrial translation factors" mTRAN1 and mTRAN2 are land plant-specific proteins, required for normal mitochondrial respiration chain biogenesis.

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TCP transcription factors play a role in a large number of developmental processes and are at the crossroads of numerous hormonal biosynthetic and signaling pathways. The complete repertoire of TCP genes has already been characterized in several plant species, but not in any species of early diverging eudicots. We focused on the order Ranunculales because of its phylogenetic position as sister group to all other eudicots and its important morphological diversity.

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Partial resistance in plants generally exerts a low selective pressure on pathogens, and thus ensuring their durability in agrosystems. However, little is known about the effect of partial resistance on the molecular mechanisms of pathogenicity, a knowledge that could advance plant breeding for sustainable plant health. Here we investigate the gene expression of during infection of pepper ( L.

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Identification of -regulatory sequences controlling gene expression is an arduous challenge that is being actively explored to discover key genetic factors responsible for traits of agronomic interest. Here, we used a genome-wide approach to investigate preferentially located motifs (PLMs) in the proximal -regulatory landscape of and . We report three groups of PLMs in both the 5'- and 3'-gene-proximal regions and emphasize conserved PLMs in both species, particularly in the 3'-gene-proximal region.

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A key aim in biology is to identify which genetic changes contributed to the evolution of form through time. Apical dominance, the inhibitory effect exerted by shoot apices on the initiation or outgrowth of distant lateral buds, is a major regulatory mechanism of plant form. Nearly a century of studies in the sporophyte of flowering plants have established the phytohormone auxin as a front-runner in the search for key factors controlling apical dominance, identifying critical roles for long-range polar auxin transport and local auxin biosynthesis in modulating shoot branching.

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Article Synopsis
  • Petal identity is linked to the APETALA3 (AP3) gene lineage, but it’s unclear how this gene network is conserved across different species with petals from various evolutionary backgrounds.
  • This study explored the gene regulatory network related to petals in the Ranunculaceae family by analyzing the gene expression differences between wild-type and mutant plants at early developmental stages.
  • Findings indicated that, despite different evolutionary origins, a small group of conserved genes is involved in determining petal identity and development across both Ranunculaceae and core eudicots.
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Trees are long-lived organisms that continuously adapt to their environments, a process in which epigenetic mechanisms are likely to play a key role. Via downregulation of the chromatin remodeler DECREASED IN DNA METHYLATION 1 (DDM1) in poplar (Populus tremula × Populus alba) RNAi lines, we examined how DNA methylation coordinates genomic and physiological responses to moderate water deficit. We compared the growth and drought response of two RNAi-ddm1 lines to wild-type (WT) trees under well-watered and water deficit/rewatering conditions, and analyzed their methylomes, transcriptomes, mobilomes and phytohormone contents in the shoot apical meristem.

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The high mutational load of mitochondrial genomes combined with their uniparental inheritance and high polyploidy favors the maintenance of deleterious mutations within populations. How cells compose and adapt to the accumulation of disadvantageous mitochondrial alleles remains unclear. Most harmful changes are likely corrected by purifying selection, however, the intimate collaboration between mitochondria- and nuclear-encoded gene products offers theoretical potential for compensatory adaptive changes.

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Plant nitrogen (N) fertilization is known to affect disease; however, the underlying mechanisms remain mostly unknown. We investigated the impact of N supply on the Arabidopsis thaliana-Botrytis cinerea interaction. A.

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  • Recent research distinguishes between core and peripheral genes in genetic networks and investigates their impact on phenotype prediction.
  • In a study with 241 cloned genotypes of Populus nigra, researchers measured 17 traits and sequenced RNA to analyze gene co-expression networks.
  • Although core genes showed less variability and greater differentiation, they did not consistently outperform peripheral genes in predicting phenotypic traits.
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  • Seeds consist of three distinct tissues: the embryo, endosperm, and maternal tissues, which makes it challenging to study their interactions without precise spatial data.
  • Researchers studied the maize kernel to uncover gene expression profiles at the interfaces between the embryo and endosperm, identifying unique transcriptomic signatures in specific layers.
  • The endosperm adjacent to the scutellum (EAS) is a newly identified tissue that develops shortly after pollination, characterized by genes related to transport and dynamic changes, including cell death and cell recruitment as the embryo grows.
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Understanding the mechanisms triggering variation of cell wall degradability is a prerequisite to improving the energy value of lignocellulosic biomass for animal feed or biorefinery. Here, we implemented a multiscale systems approach to shed light on the genetic basis of cell wall degradability in maize. We demonstrated that allele replacement in two pairs of near-isogenic lines at a region encompassing a major quantitative trait locus (QTL) for cell wall degradability led to phenotypic variation of a similar magnitude and sign to that expected from a QTL analysis of cell wall degradability in the F271 × F288 recombinant inbred line progeny.

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Background: The floral transition is a complex developmental event, fine-tuned by various environmental and endogenous cues to ensure the success of offspring production. Leaves are key organs in sensing floral inductive signals, such as a change in light regime, and in the production of the mobile florigen. CONSTANS and FLOWERING LOCUS T are major players in leaves in response to photoperiod.

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Modulation of gene expression in roots of Brassica napus by silicon (Si) supply could allow plants to cope with future stresses. The origin of the beneficial effects of silicon (Si) in plants, especially when they are subject to stress, remains poorly understood. Some authors have shown that Si alleviates plant stress and consider that this is mainly due to a mechanical effect on the cell wall.

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Article Synopsis
  • - The study focuses on Populus nigra, an important tree species, and aims to utilize RNA sequencing to identify and categorize Single Nucleotide Polymorphisms (SNPs) in its natural populations for genomic analysis.
  • - Researchers developed a bioinformatics pipeline for SNP identification from RNAseq data, validating its accuracy by comparing it to existing genetic data sources and confirming its reliability through genetic analyses.
  • - The findings highlight RNA sequencing as an effective method for accurately genotyping SNPs in P. nigra, paving the way for future studies in quantitative and population genomics.
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Sequencing of total RNA enables the study of the whole plant transcriptome resulting from the simultaneous expression of the three genomes of plant cells (located in the nucleus, mitochondrion and chloroplast). While commonly used for the quantification of the nuclear gene expression, this method remains complex and challenging when applied to organellar genomes and/or when used to quantify posttranscriptional RNA maturations. Here we propose a complete bioinformatical and statistical pipeline to fully characterize the differences in the chloroplast transcriptome between two conditions.

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Despite a long history, the production of useful alien introgression lines in wheat remains difficult mainly due to linkage drag and incomplete genetic compensation. In addition, little is known about the molecular mechanisms underlying the impact of foreign chromatin on plant phenotype. Here, a comparison of the transcriptomes of barley, wheat and a wheat-barley 7HL addition line allowed the transcriptional impact both on 7HL genes of a non-native genetic background and on the wheat gene complement as a result of the presence of 7HL to be assessed.

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Background: Genome-wide characterization of tissue- or cell-specific gene expression is a recurrent bottleneck in biology. We have developed a sensitive approach based on ultra-low RNA sequencing coupled to laser assisted microdissection for analyzing different tissues of the small Arabidopsis embryo.

Methods And Results: We first characterized the number of genes detected according to the quantity of tissue yield and total RNA extracted.

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Today, the growing knowledge and data accumulation on plant genomes do not solve in a simple way the task of gene function inference. Because data of different types are coming from various sources, we need to integrate and analyze them to help biologists in this task. We created FLAGdb ( http://tools.

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Numerous statistical pipelines are now available for the differential analysis of gene expression measured with RNA-sequencing technology. Most of them are based on similar statistical frameworks after normalization, differing primarily in the choice of data distribution, mean and variance estimation strategy and data filtering. We propose an evaluation of the impact of these choices when few biological replicates are available through the use of synthetic data sets.

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Root hairs are involved in water and nutrient uptake, and thereby in plant autotrophy. In legumes, they also play a crucial role in establishment of rhizobial symbiosis. To obtain a holistic view of Medicago truncatula genes expressed in root hairs and of their regulation during the first hours of the engagement in rhizobial symbiotic interaction, a high throughput RNA sequencing on isolated root hairs from roots challenged or not with lipochitooligosaccharides Nod factors (NF) for 4 or 20 h was carried out.

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Light is a major regulator of plant growth and development by antagonizing gibberellins (GA), and we provide evidence for a role of light perception and GA in seed coat formation and seed tolerance to deterioration. We have identified two activation-tagging mutants of Arabidopsis thaliana, cog1-2D and cdf4-1D, with improved seed tolerance to deterioration linked to increased expression of COG1/DOF1.5 and CDF4/DOF2.

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Global inspection of plant genomes identifies genes maintained in low copies across taxa and under strong purifying selection, which are likely to have essential functions. Based on this rationale, we investigated the function of the low-duplicated CYP715 cytochrome P450 gene family that appeared early in seed plants and evolved under strong negative selection. Arabidopsis CYP715A1 showed a restricted tissue-specific expression in the tapetum of flower buds and in the anther filaments upon anthesis.

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