ABSTRACT: affy_genomic_poplar - affy_genomic_poplar - The project aims to identify genes of interest for water deficit acclimation in poplar. We look for genes and gene expression networks related to drought stress in two hybrid cultivars, differing in their drought tolerance in field. Affymetrix poplar genome array was designed on several Populus species. In order to deal with comparative approaches, we checked the convenience of the array by hybridizing genomic DNA of the two hybrid cultivars (Populus deltoides × Populus nigra, namely ‘cv Carpaccio’ and ‘cv Soligo’). This point is important as transcript sequence might have diverged in the two genomes (Fossati et al, 2005), which could lead to absence of hybridization without physiological meaning. -Two poplar cultivars, Soligo (S) and Carpacio (C) were grown in controlled conditions. Mature leaves were collected and genomic DNA was extracted from leaves in CTAB buffer. gDNA was fragmented with DNAse1. DNA fragments were labelled with Biotin N6-ddATP and hybridized on Affymetrix poplar genome array. Two technical replicates per genotype were performed. Keywords: genomic comparison,gain of fuction epimutation
Project description:affy_genomic_poplar - affy_genomic_poplar - The project aims to identify genes of interest for water deficit acclimation in poplar. We look for genes and gene expression networks related to drought stress in two hybrid cultivars, differing in their drought tolerance in field. Affymetrix poplar genome array was designed on several Populus species. In order to deal with comparative approaches, we checked the convenience of the array by hybridizing genomic DNA of the two hybrid cultivars (Populus deltoides × Populus nigra, namely ‘cv Carpaccio’ and ‘cv Soligo’). This point is important as transcript sequence might have diverged in the two genomes (Fossati et al, 2005), which could lead to absence of hybridization without physiological meaning. -Two poplar cultivars, Soligo (S) and Carpacio (C) were grown in controlled conditions. Mature leaves were collected and genomic DNA was extracted from leaves in CTAB buffer. gDNA was fragmented with DNAse1. DNA fragments were labelled with Biotin N6-ddATP and hybridized on Affymetrix poplar genome array. Two technical replicates per genotype were performed. Keywords: genomic comparison,gain of fuction epimutation 4 arrays - poplar
Project description:affy_popsec_nancy_leaves_poplar - affy_popsec_nancy_leaves2007_poplar - This project aims to identify genes of interest for water deficit acclimation and/or adaptation in a tree species: poplar. We look for genes and gene expression networks related to drought stress. We intend to analyse the transcriptome in mature leaves, in two genotypes, Carpaccio and Soligo, at various stages and intensities of stress. During water deficit, leaves underwent many processes aiming to maintain cells integrity such as water status adjustment through osmoregulation or cell detoxication. These analyses intend to identify genes of interest involved in homeostasis maintenance. The comparison between medium and severe stress intensities and between early and long term stresses will power the selection of genes of interest. The co-analysis of two genotypes of contrasted tolerance to water deficit should help to discriminate genes presenting a potential adaptative character from genes responding passively to the constraint-In a first experiment, two poplar clones, Soligo (S) and Carpacio (C) were submitted to 4 treatments: control, mild water deficit, moderate water deficit (12-day long for both) and early-drought stress (about 36-h long). Growth and physiology was characterised on a batch of plants and samples collected on another batch of plants. In a second experiment, two poplar clones, Soligo (S) and Carpacio (C) were submitted to 2 treatments: control and moderate water deficit. Mature leaves were collected and total RNAs were extracted from each tree individually. Two pools of 3 (or 2) individuals were made using equimolar ratio. A pool is considered as one biological replicate and corresponds to one Affimetrix slide. Keywords: treated vs untreated comparison
Project description:affy_popsec_nancy_leaves_poplar - affy_popsec_nancy_leaves2008_poplar - This project aims to identify genes of interest for water deficit acclimation and/or adaptation in a tree species: poplar. We look for genes and gene expression networks related to drought stress. We intend to analyse the transcriptome in mature leaves, in two genotypes, Carpaccio and Soligo, at various stages and intensities of stress. During water deficit, leaves underwent many processes aiming to maintain cells integrity such as water status adjustment through osmoregulation or cell detoxication. These analyses intend to identify genes of interest involved in homeostasis maintenance. The comparison between medium and severe stress intensities and between early and long term stresses will power the selection of genes of interest. The co-analysis of two genotypes of contrasted tolerance to water deficit should help to discriminate genes presenting a potential adaptative character from genes responding passively to the constraint-In a first experiment, two poplar clones, Soligo (S) and Carpacio (C) were submitted to 4 treatments: control, mild water deficit, moderate water deficit (12-day long for both) and early-drought stress (about 36-h long). Growth and physiology was characterised on a batch of plants and samples collected on another batch of plants. In a second experiment, two poplar clones, Soligo (S) and Carpacio (C) were submitted to 2 treatments: control and moderate water deficit. Mature leaves were collected and total RNAs were extracted from each tree individually. Two pools of 3 (or 2) individuals were made using equimolar ratio. A pool is considered as one biological replicate and corresponds to one Affymetrix slide. Keywords: treated vs untreated comparison
Project description:Oligoarray expression profiling was carried out in poplar leaves upon infection with rust in order to identify genes expressed during tree defense response. For this purpose, we inoculated detached leaves of the interamerican hybrid poplar Populus trichocarpa x Populus deltoides 'Beaupré' grown in greenhouse either with spores of avirulent strain 93ID6 (incompatible interaction I48) or spores of virulent strain 98AG31 (compatible interaction C48) of the pathogenic rust fungus Melampsora larici-populina. Besides, we mock-inoculated 'Beaupré' leaves with water (control condition, T48). Detached leaves were maintained in vitro in controled conditions to allow fungal infection and colonization of plant tissue. Leaves were sampled 48 hours post-inoculation after that the fungus attempt to penetrate plant cells in mesophyll. Keywords: Plant tissue infection, Plant defense response, Oligonucleotide array
Project description:affy_popsec_nancy_leaves_poplar - affy_popsec_nancy_leaves2008_poplar - This project aims to identify genes of interest for water deficit acclimation and/or adaptation in a tree species: poplar. We look for genes and gene expression networks related to drought stress. We intend to analyse the transcriptome in mature leaves, in two genotypes, Carpaccio and Soligo, at various stages and intensities of stress. During water deficit, leaves underwent many processes aiming to maintain cells integrity such as water status adjustment through osmoregulation or cell detoxication. These analyses intend to identify genes of interest involved in homeostasis maintenance. The comparison between medium and severe stress intensities and between early and long term stresses will power the selection of genes of interest. The co-analysis of two genotypes of contrasted tolerance to water deficit should help to discriminate genes presenting a potential adaptative character from genes responding passively to the constraint-In a first experiment, two poplar clones, Soligo (S) and Carpacio (C) were submitted to 4 treatments: control, mild water deficit, moderate water deficit (12-day long for both) and early-drought stress (about 36-h long). Growth and physiology was characterised on a batch of plants and samples collected on another batch of plants. In a second experiment, two poplar clones, Soligo (S) and Carpacio (C) were submitted to 2 treatments: control and moderate water deficit. Mature leaves were collected and total RNAs were extracted from each tree individually. Two pools of 3 (or 2) individuals were made using equimolar ratio. A pool is considered as one biological replicate and corresponds to one Affymetrix slide. Keywords: treated vs untreated comparison 8 arrays - poplar
Project description:affy_popsec_nancy_leaves_poplar - affy_popsec_nancy_leaves2007_poplar - This project aims to identify genes of interest for water deficit acclimation and/or adaptation in a tree species: poplar. We look for genes and gene expression networks related to drought stress. We intend to analyse the transcriptome in mature leaves, in two genotypes, Carpaccio and Soligo, at various stages and intensities of stress. During water deficit, leaves underwent many processes aiming to maintain cells integrity such as water status adjustment through osmoregulation or cell detoxication. These analyses intend to identify genes of interest involved in homeostasis maintenance. The comparison between medium and severe stress intensities and between early and long term stresses will power the selection of genes of interest. The co-analysis of two genotypes of contrasted tolerance to water deficit should help to discriminate genes presenting a potential adaptative character from genes responding passively to the constraint-In a first experiment, two poplar clones, Soligo (S) and Carpacio (C) were submitted to 4 treatments: control, mild water deficit, moderate water deficit (12-day long for both) and early-drought stress (about 36-h long). Growth and physiology was characterised on a batch of plants and samples collected on another batch of plants. In a second experiment, two poplar clones, Soligo (S) and Carpacio (C) were submitted to 2 treatments: control and moderate water deficit. Mature leaves were collected and total RNAs were extracted from each tree individually. Two pools of 3 (or 2) individuals were made using equimolar ratio. A pool is considered as one biological replicate and corresponds to one Affimetrix slide. Keywords: treated vs untreated comparison 16 arrays - poplar
Project description:Microarray expression profiling was carried out in poplar leaves upon infection with rust in order to identify genes expressed during tree defense response. For this purpose, we inoculated detached leaves of the interamerican hybrid poplar Populus trichocarpa x Populus deltoides 'Beaupré' grown in greenhouse with spores of avirulent strain 93ID6 of the pathogenic rust fungus Melampsora larici-populina (incompatible interaction, I48). Besides, we mock-inoculated 'Beaupré' leaves with water (control condition, T48). Detached leaves were maintained in vitro in controled conditions to allow fungal infection and colonization of plant tissue. Leaves were sampled 48 hours post-inoculation after that the fungus attempt to penetrate plant cells in mesophyll. Competitive hybridization between transcripts of incompatible interaction (I48) and control condition (T48) was done on Populus PICME 28K cDNA microarray. Keywords: Time-course infection of plant tissue, defense response, cDNA microarray
Project description:We performed that comprehensive identification of genes responsible for stress tolerance by analyzing the whole-genome expression profiles of poplar (Populus alba × P. glandulosa) leaves exposed to drought and salt stresses. Examination at the molecular level how this tree species responds to drought and salt stresses by regulating the expression of genes involved in signal transduction, transcriptional regulation, and stress responses.
Project description:As exposure to episodic drought can impinge significantly on forest health and the establishment of productive tree plantations, there is great interest in understanding the mechanisms of drought response in trees. The ecologically dominant and economically important genus Populus, with its sequenced genome, provides an ideal opportunity to examine transcriptome level changes in trees in response to a drought stimulus. The transcriptome level drought response of two commercially important hybrid Populus clones (P. deltoides · P. nigra, DN34, and P. nigra · P. maximowiczii, NM6) was characterized over a diurnal period using a 4 · 2 · 2 completely randomized factorial ANOVA experimental design (four time points, two genotypes, and two treatment conditions) using Affymetrix Poplar GeneChip microarrays. Notably, the specific genes that exhibited changes in transcript abundance in response to drought differed between the genotypes and/or the time of day that they exhibited their greatest differences. This study emphasizes the fact that it is not possible to draw simple, generalized conclusions about the drought response of the genus Populus on the basis of one species, nor on the basis of results collected at a single time point. The data derived from our studies provide insights into the variety of genetic mechanisms underpinning the Populus drought response, and provide candidates for future experiments aimed at understanding this response across this economically and ecologically important genus.