Project description:St (common potato) is a freezing sensitive species unable to cold acclimate. The close wild relative Sc is freezing tolerant and able to cold acclimate. Here we compare the cold transcriptome of these two species with different levels of freezing tolerance. We also identify the putative CBF regulons by comparing the transcriptomes of wild type plants with that of 35S::AtCBF3 transgenic lines in both species.
Project description:The potato is susceptible to water stress at all stages of development. We examined four clones of tetraploid potato, Cardinal, Desirée, Clone 37 FB and Mije, from the germplasm bank of the National Institute of Agricultural Research (INIA) in Chile. Water stress was applied by suspending irrigation at the beginning of tuberization. Stomatal conductance, tuber and plant fresh and dry weight was used to categorize water stress tolerance. Cardinal had high susceptibility to water stress. Desirée was less suscepetible than Cardinal and had some characteristics of tolerance. Mije had moderate and Clon 37 FB high tolerance. Differential gene expression in leaves from plants with and without water stress were examined using transcriptome sequencing. Water stress susceptible Cardinal had the fewest differentially expressed genes at 101, compared to Desirée at 1867, Clon 37 FB at 1179 and Mije at 1010. Water stress tolerance was associated with up-regulation of expression of transcription factor genes and genes involved in osmolyte and polyamine biosynthesis. Increased expression of genes encoding late embryogenesis abundant (LEA) and dehydrin proteins along with decreased expression of genes involved in nitrate assimilation and amino acid metabolism were found for clones showing water stress tolerance. The results also show that water deficit was associated with reduced biotic stress responses. Additionally, heat shock protein genes were differentially expressed in all clones except for highly susceptible Cardinal. Together the gene expression study demonstrates variation in the molecular pathways and biological processes in response to water stress contributing to tolerance and susceptibility.
Project description:The molecular response to salt exposure was studied in the leaves of a S. tuberosum clone using cDNA microarray. Differentially expressed genes were classified according to their known or predicted function and their expression ratio as compared to the control. The major changes upon a 150 mM NaCl exposure in potato leaves occurred in the photosystem apparatus and Calvin cycle: many transcripts coding for proteins belonging to photosystems I and II and chlorophyll synthesis were repressed. On the other hand, we observed the induction of various kinds of transcription factors implicated in osmotic stress response via ABA-dependent or ABA-independent pathways but also in plant defense pathways. This revealed a crosstalk between abiotic and biotic stress responses during salt exposure, which activated several adaptation mechanisms including HSP, LEA, dehydrins and PR proteins. Gene expression changes related to carbohydrate and amino acid metabolism were also observed, pointing at putative modifications at the metabolic level.
Project description:Biotic and abiotic stresses limit agricultural yields, and plants are often simultaneously exposed to multiple stresses. Combinations of stresses such as heat and drought or cold and high light intensity, have profound effects on crop performance and yeilds To analyze such responses, we initially compared transcriptome changes in ten Arabidopsis thaliana ecotypes using cold, heat, high light, salt and flagellin treatments as single stress factors or their double combinations. Arabidopsis thaliana plants of ecotypes (Col, Ler, C24, Cvi, Kas1, An1, Sha, Kyo2, Eri and Kond) were subjected to the following stress treatments: Salt, Cold, Heat, High Light (HL), Salt+Heat, Salt+HL, Cold+HL, Heat+HL, as well as FLG (Flagellin, flg22 peptide), Cold+FLG, Heat+FLG
Project description:Potato seedlings were subjected to cold, heat and salt stress. Expression profiles were captured at three different time-points, 3h, 9h and 27h from two different tissues, roots and leaves. The experiment was preformed independently three times. Commercially available true potato seeds (Variety Gilroy) were germinated on rafts floating on hydroponic medium in Magenta boxes. Plants were grown for 5 weeks prior to stress application under long day conditions (16h light and 8h dark) at 25C with gentle agitation. To initiate stress the medium was replaced with fresh medium pre-chilled to 4C (cold stress), pre-heated to 35C (heat stress) or supplemented with 100mM NaCl (salt stress). Cold and heat stress were maintained for the duration of the experiment by placing the Magenta boxes on ice or in a water-bath at 35C. For every individual sample two boxes of plants were used pooling a total of 6 plants per sample. For each time-point a single control sample was used by changing the media in a similar way as for the stress induction. A total of six boxes were combined for the pooled reference samples. Plants were harvested at the appropriate time and snap-frozen in liquid nitrogen. Roots and aerial tissue was separated prior to freezing. The tissue was stored at -80C freezer until isolation. Total RNA was isolated using RNeasy isolation kit. The intactness of the RNA was verified on gel and the concentration was adjusted to 3ug/ul by ethanol precipitation and re-suspension. Series_weblink: http://www.tigr.org/tdb/potato Keywords = potato, Abiotic stress Keywords: ordered
Project description:Potato seedlings were subjected to cold, heat and salt stress. Expression profiles were captured at three different time-points, 3h, 9h and 27h from two different tissues, roots and leaves. The experiment was preformed independently three times. Commercially available true potato seeds (Variety Gilroy) were germinated on rafts floating on hydroponic medium in Magenta boxes. Plants were grown for 5 weeks prior to stress application under long day conditions (16h light and 8h dark) at 25C with gentle agitation. To initiate stress the medium was replaced with fresh medium pre-chilled to 4C (cold stress), pre-heated to 35C (heat stress) or supplemented with 100mM NaCl (salt stress). Cold and heat stress were maintained for the duration of the experiment by placing the Magenta boxes on ice or in a water-bath at 35C. For every individual sample two boxes of plants were used pooling a total of 6 plants per sample. For each time-point a single control sample was used by changing the media in a similar way as for the stress induction. A total of six boxes were combined for the pooled reference samples. Plants were harvested at the appropriate time and snap-frozen in liquid nitrogen. Roots and aerial tissue was separated prior to freezing. The tissue was stored at -80C freezer until isolation. Total RNA was isolated using RNeasy isolation kit. The intactness of the RNA was verified on gel and the concentration was adjusted to 3ug/ul by ethanol precipitation and re-suspension. Series_weblink: http://www.tigr.org/tdb/potato Keywords = potato, Abiotic stress
Project description:The molecular response to salt exposure was studied in the leaves of a S. tuberosum clone using cDNA microarray. Differentially expressed genes were classified according to their known or predicted function and their expression ratio as compared to the control. The major changes upon a 150 mM NaCl exposure in potato leaves occurred in the photosystem apparatus and Calvin cycle: many transcripts coding for proteins belonging to photosystems I and II and chlorophyll synthesis were repressed. On the other hand, we observed the induction of various kinds of transcription factors implicated in osmotic stress response via ABA-dependent or ABA-independent pathways but also in plant defense pathways. This revealed a crosstalk between abiotic and biotic stress responses during salt exposure, which activated several adaptation mechanisms including HSP, LEA, dehydrins and PR proteins. Gene expression changes related to carbohydrate and amino acid metabolism were also observed, pointing at putative modifications at the metabolic level. Gene expression has been followed at two different time-points (one and three day after salinity treatment) and conditions: salt-treatment (150 mM NaCl) and control conditions. For each time-point and conditions 3 independent biological replicates were sampled.