Metabolomics,Unknown,Transcriptomics,Genomics,Proteomics

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Hybrid_Poplar_H11-11_Leaves_Local_Stress_Response_DataSet1

ABSTRACT: We investigated the transcriptional response of hybrid poplar (Populus trichocarpa x deltoides) leaves to a variety of stress treatments (insect feeding by Malacosoma disstria larvae, mechanical wounding, and wounding plus the application of insect oral secretions) over a 24 hour time course. Experiments were conducted using clonal trees under greenhouse conditions at the University of British Columbia. We used the 15.5K poplar cDNA microarray platform previously described by Ralph et al. (Molecular Ecology 2006, 15:1275-1297). Differentially expressed genes were determined using three criteria: fold-change between treated and untreated control leaves > 1.5-fold, P value < 0.05 and Q value < 0.05. This study identified > 1,000 differentially expressed genes in response to insect feeding and/or treatments that mimic insect feeding damage. A factorial hybridization design was chosen to assess gene expression among the untreated control leaves, and leaves subjected to one of three stress treatments: forest tent caterpillar (Malacosoma disstria) feeding, mechanical wounding, and mechanical wounding plus the application of forest tent caterpillar oral secretions. For each tree, the lowest five mature leaves were caged in nylon mesh bags, treated or left untreated as a control. Leaves were harvested 2, 6 or 24 hours after the initiation of each treatment and total RNA was individually isolated from each tree. For each treatment and time point, equal amounts of total RNA were combined from each of the five biological replicate trees prior to cDNA microarray analysis. For the herbivory, mechanical wounding and oral secrection treatments, total RNA from treated and untreated control leaves was compared using a balanced loop consisting of direct and indirect comparisons across treatments and time points, with dye balance, using a total of 54 hybridizations.

ORGANISM(S): Populus trichocarpa x Populus deltoides

SUBMITTER: Joerg Bohlmann

PROVIDER: E-GEOD-13767 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Hybrid_Poplar_H11-11_Leaves_Local_Stress_Response_DataSet1

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