Circad_pop1-circadian rhythm in the expression of genes involved in the formation of poplar wood
Ontology highlight
ABSTRACT: affy_orleans_circad - circad_pop1 - Global transcriptome analysis of tension wood in poplar over a 24h period. Young differentiating xylem was harvested on the tension wood side of 6 month-old poplar trees grown in greenhouse conditions. The samples were harvested at 6 hour intervals throughout the day. The bioinformatic analysis will permit the identification of genes expressed in tension wood and that cycle with a nycthemeral oscillation pattern. Keywords: time course 10 arrays - poplar
Project description:affy_popsec_orleans_poplar - xyleme - This project aims to identify candidate genes for water deficit acclimation and/or adaptation in a tree species: poplar. Due to compelling evidence that transcriptional regulation plays a major role in regulating many biological processes, we will look for genes and gene expression networks related to drought stress. We intend to analyse the transcriptome in two poplar genotypes of contrasted tolerance to water deficit, at various stages and intensities of stress and simultaneously in whole xylem and cambial zone from young trees. The co-analysis of two genotypes of contrasted tolerance to water deficit should allow to better discriminating genes presenting a potential adaptative character from genes responding passively to the constraint. The consideration of both whole xylem and cambial zone will enable us to discriminate between regulations events originating from very young xylem cells undergoing their first steps of xylem differentiation (cambial zone) compared to whole xylem sample enriched in more differentiated xylem cells and parenchyma ray cells.-Two poplar clones, named Soligo (S) and Carpaccio (C) were submitted to 4 treatments: non-stressed control, severe-drought stress, mild-drought stress and early-drought stress. Two pools of 2 or 3 trees were considered as biological replicates. Two different samples were collected on each individual tree: whole stem xylem (X) and cambial zone plus very young expanding xylem (Y). Total RNAs were extracted from each tree and assemble in pool of 3 or 2 individuals using equimolar ratio for each X and for Y. One affymetrix slide corresponds to one pooled RNA sample (X or Y). A total number of slides : 4 treatments x 2 clones x 2 tissues x 2 biological replicates (pool) = 32 slides, will be done. Keywords: genotype and ecotype comparison,organ comparison,treated vs untreated comparison 32 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:affy_popsec_nancy_roots_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 root apices, in two genotypes, Carpaccio and Soligo, at various stages and intensities of stress. Root apex is the location of root elongation and these analyses intend to identify genes involved in the control of cell expansion and thus of root elongation. Indeed, root growth maintenance in response to water shortage contributes to plant tolerance to water deficit. 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 better discriminate genes presenting a potential adaptative character from genes responding passively to the constraint.-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. Four to eight root apices (1 cm-long) were collected on each individual tree. Total RNAs were extracted from all roots for 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. The two biological replicates originate from the same experiment. Keywords: treated vs untreated comparison 16 arrays - poplar
Project description:affy_orleans_circad - circad_pop1 - Global transcriptome analysis of tension wood in poplar over a 24h period. Young differentiating xylem was harvested on the tension wood side of 6 month-old poplar trees grown in greenhouse conditions. The samples were harvested at 6 hour intervals throughout the day. The bioinformatic analysis will permit the identification of genes expressed in tension wood and that cycle with a nycthemeral oscillation pattern. Keywords: time course
Project description:affy_pop_2011_08 - poplar estradiol study - genes regulated by PtaZFP2 in absence of mechanical stress - genes regulated by PtaZFP2 after one bending.Species: Populus tremula x Populus alba-The laboratory previously established a poplar transgenic line overexpressing PtaZFP2 under the control of an estradiol-inducible promoter. - the experiment, conducted on 3-month-old hydroponically-grown poplars, consists in the comparison of WT poplars treated with estradiol and the PtaZFP2-overexpressing line treated with estradiol. We also compared unbent and bent PtaZFP2-overexpressing poplars. The applied strain is quantitatively controlled (Coutand & Moulia, 2000, JExpBot; coutand et al., 2009, Plant Physiology) 9 arrays - poplar; time course
Project description:affy_pop_2011_08 - poplar bent study - genes regulated by PtaZFP2 in absence of mechanical stress - genes regulated by PtaZFP2 after one bending.Species: Populus tremula x Populus alba-- The laboratory previously established a poplar transgenic line overexpressing PtaZFP2 under the control of an estradiol-inducible promoter. - the experiment, conducted on 3-month-old hydroponically-grown poplars, consists in the comparison of WT poplars treated with estradiol and the PtaZFP2-overexpressing line treated with estradiol. We also compared unbent and bent PtaZFP2-overexpressing poplars. The applied strain is quantitatively controlled (Coutand & Moulia, 2000, JExpBot; coutand et al., 2009, Plant Physiology) - 27 arrays - poplar; gene knock in (transgenic) 27 samples are wt; for this experiment only the bending comparaison are studied.
Project description:affy_rewatering_poplar - rewatering - Biological question (15 lines max): Xylogenesis is a complex process and is highly influenced by environmental factors. Numerous studies have shown xylem structural acclimation to moderate and long-lasting water deficits. A decrease in cell lumen size and an increase in vessel density are generally observed. Other preliminary experiments in our laboratory focusing on a short and progressive drought-rewatering cycle in poplar show a gradual decrease in fibre size with decreasing water availability and an important rise in vessel number with irrigation recovery. This suggests a reorientation during the early stages of cambial derivatives differentiation towards vessel formation. The aim of this study is to characterize global gene expression in young differentiating xylem of poplar in response to a drought-rewatering cycle. Results should provide a comprehensive genomic basis for the xylem structural modifications observed.-The experimental design consisted in a differential water supply. Experiments were done on tilted trees to induce tension wood formation. Trees were regularly irrigated at full capacitance until July 18, 2007, the beginning of the experiment. Two sets of plants were designed. For each set, irrigation was withheld until July 25, 2007. At this time, one of the two sets (treated-sample) was re-irrigated at full capacitance during 14hrs (WDR) while the other one was maintained under water deficit (WD). Samples were collected after the 14hrs for all trees. Keywords: treated vs untreated comparison 6 arrays - poplar
Project description:Young poplar stems show a preponderantly primary growth in the top internodes and differential cambium activity in the basal internodes after inclination with some tension wood formed after 45 min. This study was conducted in order to characterize the early changes in gene expression during early stages of the gravitropic response in the poplar.
Project description:affy_rnai_cadpoplar - affy_rnai_cadpoplars - This experiment aims to characterize global gene expression in young xylem of transgenic RNAi-CAD poplars in comparison to WT poplars. Cinnamyl Alcohol Dehydrogenase (CAD) is the final enzyme involved in the monolignol biosynthesis pathway. Transgenic poplars were produced using RNAi strategy (pHellsgate 8 vector, Helliwell and Waterhouse, 2003) and exhibited the expected phenotype (red xylem, reduced CAD activity).Biological question (15 lines max):This experiment aims to characterize global gene expression in young xylem of transgenic RNAi-CAD poplars in comparison to WT poplars. Cinnamyl AlcoholDehydrogenase (CAD) is the final enzyme involved in the monolignol biosynthesispathway.Transgenic poplars were produced using RNAi strategy (pHellsgate 8 vector, Helliwell and Waterhouse, 2003) and exhibited the expectedphenotype (red xylem, reduced CAD activity). -RNAi-CAD transgenic poplars were produced using hairpin RNAi strategy (pHellsgate 8 vector, Helliwell and Waterhouse, 2003). For this transcriptome anaylsis, 2 independent transgenic lines (named pHG8-CAD2 and pHG8-CAD19) from the same transformation procedure were used as biological repeats. Four-month-old poplar plants were inclined at 30° in the greenhouse and sampled after 26 days. Young differentiating xylem originating from the lower side of stems - opposite wood - (ODX) was sampled on each individual tree by scrapping slightly the debarked stem with a scalpel. Samples were immediately flash frozen in liquid nitrogen, ground with mortar and pestle, and total RNAs were extracted from fine ground powder using the QIAGEN miRNeasy kit according to the manufacturer. One Affymetrix slide corresponds to a pool of RNA samples from 2-4 individual trees (WT, RNAi-CAD transgenic lines 2 and 19). Total number of slides = 2 genotypes (WT/RNAi line) x 1 tissue x 2 biological replicates = 4 slides were done. 4 arrays - poplar; normal vs rnai mutant comparaison
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