Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Effect of drought on herbivore-induced plant gene expression: Population comparison for range limit inferences

ABSTRACT: Low elevation âtrailing edgeâ range margin populations typically face increases in both abiotic and biotic stressors that may contribute to range limit development. We hypothesize that selection may act on ABA and JA signaling pathways for more stable expression needed for range expansion, but that antagonistic crosstalk prevents their simultaneous co-option. To test this hypothesis, we compared high and low elevation populations of Boechera stricta that have diverged for constitutive levels of glucosinolate defenses and root:shoot ratios; neither population has high levels of both traits. If constraints imposed by antagonistic signaling underlies this divergence, one would predict that high constitutive levels of traits would coincide with lower plasticity. To test this prediction, we compared the genetically diverged populations in a double challenge drought-herbivory growth chamber experiment. Although a glucosinolate defense response to the generalist insect herbivore Spodoptera exigua was attenuated under drought conditions, the plastic defense response did not differ significantly between populations. Similarly, although several potential drought tolerance traits were measured, only stomata aperture behavior, as measured by carbon isotope ratio, was less plastic as predicted in the high elevation population. However, RNAseq results on a small subset of plants indicated differential expression of relevant genes between populations as predicted. We suggest that the ambiguity in our results comes from a weaker link between the pathways and the functional traits compared to transcripts. Examination of four different treatments on two different populations

ORGANISM(S): Boechera stricta

SUBMITTER: Gunbharpur Gill

PROVIDER: E-GEOD-78101 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

ACCESS DATA

Similar Datasets

Project description:Detailed information: Rice (*Oryza sativa* L. cv. Nipponbare) is a drought-susceptible species which is well suited for studies of abiotic stress response because of the comprehensive bioinformatics resource available. By withholding water from the entire root system of young rice plants, or half the root system only, it was possible to infer the relative impact of signals arriving from roots growing in wet and dry soil on the shoot proteome. The global proteome of shoots had 685 proteins in common to all three drought treatments but there were major shifts in abundance of individual proteins within 16 functional categories. The dominant changes were analyzed more deeply. First, we investigated transport and cell component organization, where some proteins were up-regulated by drought but many more down-regulated. Proteins involved in protein metabolism were up-regulated in general by drought when they were responsible for protein degradation but those involved in protein synthesis were down-regulated when water was withheld. Stress-related proteins behaved very consistently by increasing in droughted plants but notably some proteins were most abundant when roots of the same plant were growing in both wet and dry soil. This suggests that drought signals are complex interactions and not simply the additive effect of water supply to the roots. Changes in carbohydrate-processing proteins were consistent with the passive accumulation of soluble sugars in shoots under drought, with hydrolysis of sucrose and starch synthesis both enhanced. Data analysis information: The result raw files were converted to mzXML format and processed through the global proteome machine (GPM) software (version 2.1.1) of the X!Tandem algorithm (freely available at http://www.thegpm.org). The 16 gel fractions were processed serially for each experiment and the output files were generated as non-redundant, merged files with protein identifications with log (e) values less than -1, for each individual gel fraction. A protein database compiled from NCBI *O*. *sativa* with 26938 protein sequences (August 2011) was used in GPM to search the tandem mass spectra; the database also included common trypsin and human peptide contaminants. False discovery rates (FDR) were evaluated by searching against a reversed sequence database. Search parameters included MS and MS/MS tolerances of +2 Da and +0.2 Da, carbamidomethylation of cysteine as fixed modifications, oxidation of methionine as variable modifications and tolerance of two missed tryptic cleavages and K/R-P cleavages.

Project description:Drought stress is a major problem around the world and although progress in understanding how vegetable crops and model plants adapt to drought have been made, there is still little information about how fruit crops deal with moderate drought stress. In this study, we investigated the response of two apple genotypes: a drought-sensitive genotype (M26) and a drought-tolerant genotype (MBB). Our results of the morphology, physiology and biochemistry under moderate drought stress, indicated that relative water content (RWC) and leaf area (LA) were not significant changes in two genotypes. However, it had larger leaf mass per area (LMA), and accumulated higher free proline (CFP), soluble sugars (CSS) and malonaldehyde (MDA) in the leaves. Thus, it appears that the MBB genotype could produce more osmosis-regulating substances. Phosphoproteomic was analyzed from leaves of both genotypes under moderate drought stress using the isobaric tags for relative and absolute quantification (iTRAQ) technology. A total of 595 unique phosphopeptides, 682 phosphorylated sites and 446 phosphoproteins were quantitatively analyzed in the two genotypes. Motif analyses of the phosphorylation sites showed that six motifs including [PxsP], [sP], [sD], [Rxxs], [sxP] and [sxs] were enriched. We identified 12 and 48 PLSC phosphoproteins in M26 and MBB, respectively. Among these, 9 PLSC phosphoproteins were common to both genotypes, perhaps indicating a partial overlaps of the mechanisms to moderate drought stress. Gene ontology analyses revealed that the PLSC phosphoproteins present a unique combination of metabolism, transcription, translation and protein processing, suggesting that the response in apple to moderate drought stress encompasses a new homeostasis of major cellular processes. The basic trend was an increase in protein abundance related to drought and organic substance upon moderate drought stress between two genotypes. These increases were higher in the drought-tolerant genotype (MBB) than in the drought-sensitive genotype (M26). The 23 differentially expressed mRNA encoding phosphoproteins were analysis by quantitative real-time PCR (qRT-PCR). Our study is the first to address the phosphoproteome of a major fruit crop, apple rootstocks, in response to moderate drought stress, and provide insights into the molecular regulation mechanisms of apple rootstock under moderate drought stress.

Dataset Information

Effect of drought on herbivore-induced plant gene expression: Population comparison for range limit inferences

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets