Project description:To gain insights into molecular mechanisms of tolerance to heat stress, we conducted a transcript profiling experiment to identify heat-responsive genes in contrasting peanut mini core accessions, either un-acclimated or acclimated to heat stress. Plants at reproductive stage were exposed to 28 °C (control), 45 °C for 15 d (un-acclimated) or 45 °C for 1 d followed by 7 d recovery and 15 d stress (acclimated). Two contrasting genotypes showing diverse response to stress were selected based on a bioassay involving chlorophyll fluorescence yield under elevated respiratory demand and membrane thermostability. Transcript profiling was performed using 8 x 15k custom oligo microarrays containing 15k peanut EST sequences. Gene enrichment analysis was performed using Blast2GO program and genes with homology to known proteins were categorized into detailed molecular functional groups. Majority of stress-responsive genes assigned to KEGG pathways belonged to starch, sucrose and galactose metabolism followed by aminoacid metabolism, and secondary metabolite biosynthesis. Differentially expressed transcripts from samples were validated in the samples from second year by quantitative real-time PCR. Transcripts of eight genes involved in terpenoid and flavanoid biosynthesis were induced after second and seventh day, respectively in leaves under heat stress. Metabolite analysis confirmed increases in metabolites of selected pathways under heat stress. The heat up-regulated genes in tolerant COC041 mini-core accession are potential candidate genes for engineering stress-tolerant peanuts and unraveling molecular mechanisms of peanut adaptation to heat stress. We used Agilent peanut microarrays to identify putative heat stress-responsive genes. Acclimated leaf tissues of the peanut genotypes COC041 (tolerant) and COC166 (susceptible) were used in the study. Three replications of microarray experiments were carried out by hybridizing the cRNA from different time points and stress conditions in a loop design on 8 x 15k microarray.
Project description:To gain insights into molecular mechanisms of tolerance to heat stress, we conducted a transcript profiling experiment to identify heat-responsive genes in contrasting peanut mini core accessions, either un-acclimated or acclimated to heat stress. Plants at reproductive stage were exposed to 28 °C (control), 45 °C for 15 d (un-acclimated) or 45 °C for 1 d followed by 7 d recovery and 15 d stress (acclimated). Two contrasting genotypes showing diverse response to stress were selected based on a bioassay involving chlorophyll fluorescence yield under elevated respiratory demand and membrane thermostability. Transcript profiling was performed using 8 x 15k custom oligo microarrays containing 15k peanut EST sequences. Gene enrichment analysis was performed using Blast2GO program and genes with homology to known proteins were categorized into detailed molecular functional groups. Majority of stress-responsive genes assigned to KEGG pathways belonged to starch, sucrose and galactose metabolism followed by aminoacid metabolism, and secondary metabolite biosynthesis. Differentially expressed transcripts from samples were validated in the samples from second year by quantitative real-time PCR. Transcripts of eight genes involved in terpenoid and flavanoid biosynthesis were induced after second and seventh day, respectively in leaves under heat stress. Metabolite analysis confirmed increases in metabolites of selected pathways under heat stress. The heat up-regulated genes in tolerant COC041 mini-core accession are potential candidate genes for engineering stress-tolerant peanuts and unraveling molecular mechanisms of peanut adaptation to heat stress.
Project description:To gain insights into molecular mechanisms of tolerance to heat stress, we conducted a transcript profiling experiment to identify heat-responsive genes in contrasting peanut mini core accessions, either un-acclimated or acclimated to heat stress. Plants at reproductive stage were exposed to 28 °C (control), 45 °C for 15 d (un-acclimated) or 45 °C for 1 d followed by 7 d recovery and 15 d stress (acclimated). Two contrasting genotypes showing diverse response to stress were selected based on a bioassay involving chlorophyll fluorescence yield under elevated respiratory demand and membrane thermostability. Transcript profiling was performed using 4 x 44k custom oligo microarrays containing 22k peanut EST sequences. The microarray analysis identified 710 stress-induced and 770 stress-repressed putative heat-responsive transcripts in the tolerant genotype. Gene enrichment analysis was performed using Blast2GO program and genes with homology to known proteins were categorized into detailed molecular functional groups. Majority of stress-responsive genes assigned to KEGG pathways belonged to starch, sucrose and galactose metabolism followed by amino acid metabolism, and secondary metabolite biosynthesis. Differentially expressed transcripts from samples obtained from first year’s experiment were validated in the samples from second year by quantitative real-time PCR. Transcripts of eight genes involved in terpenoid and flavanoid biosynthesis were induced after second and seventh day, respectively, in leaves under heat stress. Metabolite analysis confirmed increases in metabolites of selected pathways under heat stress. The heat up-regulated genes in tolerant COC041 mini-core accession are potential candidate genes for engineering stress-tolerant peanuts and unraveling molecular mechanisms of peanut adaptation to heat stress. We used Agilent peanut microarrays to identify putative heat stress-responsive genes. Directly heat-stressed leaf tissues of the peanut genotypes COC041 (tolerant) and COC166 (susceptible) were used in the study. Three replications of microarray experiments were carried out by hybridizing the cRNA from different time points and stress conditions in a loop design on 4 x 44k microarray.
Project description:To gain insights into molecular mechanisms of tolerance to heat stress, we conducted a transcript profiling experiment to identify heat-responsive genes in contrasting peanut mini core accessions, either un-acclimated or acclimated to heat stress. Plants at reproductive stage were exposed to 28 °C (control), 45 °C for 15 d (un-acclimated) or 45 °C for 1 d followed by 7 d recovery and 15 d stress (acclimated). Two contrasting genotypes showing diverse response to stress were selected based on a bioassay involving chlorophyll fluorescence yield under elevated respiratory demand and membrane thermostability. Transcript profiling was performed using 4 x 44k custom oligo microarrays containing 22k peanut EST sequences. The microarray analysis identified 710 stress-induced and 770 stress-repressed putative heat-responsive transcripts in the tolerant genotype. Gene enrichment analysis was performed using Blast2GO program and genes with homology to known proteins were categorized into detailed molecular functional groups. Majority of stress-responsive genes assigned to KEGG pathways belonged to starch, sucrose and galactose metabolism followed by amino acid metabolism, and secondary metabolite biosynthesis. Differentially expressed transcripts from samples obtained from first year’s experiment were validated in the samples from second year by quantitative real-time PCR. Transcripts of eight genes involved in terpenoid and flavanoid biosynthesis were induced after second and seventh day, respectively, in leaves under heat stress. Metabolite analysis confirmed increases in metabolites of selected pathways under heat stress. The heat up-regulated genes in tolerant COC041 mini-core accession are potential candidate genes for engineering stress-tolerant peanuts and unraveling molecular mechanisms of peanut adaptation to heat stress.
Project description:This SuperSeries is composed of the following subset Series: GSE16492: Expression profiling of heat stress response in peanut using oligonucleotide microarrays GSE18107: Study of acquired thermotolerance response in peanut using oligonucleotide microarrays Refer to individual Series
Project description:Subspecies of the Atlantic killifish, Fundulus heteroclitus, differ in their maximum thermal tolerance. To determine whether there is a link between the heat shock response (HSR) and maximum thermal tolerance, we exposed 20ºC acclimated killifish from these subspecies to a 2hr heat shock at 34ºC and examined gene expression during heat shock and recovery using real time quantitative PCR and a heterologous cDNA microarray designed for salmonid fishes. Keywords: Expression profiling by array
Project description:'Potato is particularly vulnerable to increased temperature, considered to be the most important uncontrollable factor affecting growth and yield. Here we describe an acquired thermotolerance response in potato, whereby treatment at a mildly elevated temperature (''acclimated'') primes the plant for more severe heat stress compared to control (''non-acclimated'') plants. We define the time course for acquiring thermotolerance and demonstrate that light is essential for the process. Physiological, transcriptomic and metabolomic approaches were employed to elucidate potential mechanisms that underpin the acquisition of heat tolerance and indicate a role for cell wall modification, auxin and ethylene signalling, and chromatin remodelling in acclimatory priming.'
Project description:'Potato is particularly vulnerable to increased temperature, considered to be the most important uncontrollable factor affecting growth and yield. Here we describe an acquired thermotolerance response in potato, whereby treatment at a mildly elevated temperature (''acclimated'') primes the plant for more severe heat stress compared to control (''non-acclimated'') plants. We define the time course for acquiring thermotolerance and demonstrate that light is essential for the process. Physiological, transcriptomic and metabolomic approaches were employed to elucidate potential mechanisms that underpin the acquisition of heat tolerance and indicate a role for cell wall modification, auxin and ethylene signalling, and chromatin remodelling in acclimatory priming. This experiment identifies changes in transcript level were measured over a time course (0, 2, 6, 12 h) during the period of acquisition of thermotolerance following transfer from 18 °C (non-acclimated) to 25 °C (acclimated). Related experiment (E-MTAB-5857) looks to understand the mechanisms by which acclimation results in protection of leaves at extreme temperature; gene expression patterns were determined in leaves from acclimated and non-acclimated plants which were subsequently transferred to 40 °C and compared during a 48 h time course (2, 6, 12, 24 h).'
Project description:To understand faster reinduction of heat acclimation, in this investigation we studied global stress associated genomic response during acclimation, following its loss and re-induction. Nylon cDNA Atlas Array was used. Collectively, the study comprised nine experimental groups of which six characterized experimental basal conditions: Controls-untreated, Short and Long term heat acclimated groups ( exposure to environmental heat at 34oC for 2 or 30 days respectively), Deacclimated group (24oC for 1mo) and Reacclimated groups (2d at 34oC following the deacclimation protocol). Three additional experimental groups: Controls, Short and Long term and Reacclimated rats (as above) were tested for genomic responses following subjection to heat stress at 41oC. Because of a dichotomy between genomic and physiological responses we hypothesize thst rapid reacclimation is linked to reprograming of gene expression. Keywords: heart, Left ventricle