Project description:Rice (Oryza sativa), the major staple food crop is being cultivated under varying ecosystems ranging from irrigated lowland to rainfed upland environments. Improvement in the rice production under drought prone unfavourable environment depends on the development of drought tolerant genotypes which needs thorough understanding of physiological and molecular events behind the tolerance mechanism. There is considerable genetic variation for drought tolerance mechanism within the cultivated gene pool. To understand the diversity of drought response, two indica rice genotypes namely, i) Apo, an up-land drought tolerant indica veriety from Philippines and ii) IR64, a popular high yielding drought susceptible genotype were selected for this study. We used the 22K rice Oligoarray from Agilent technologies to study the transcript profile in the leaves of the two contrasting rice genotypes under control and drought stressed conditions during vegetative phase. Keywords: Drought response We used Agilent rice gene chips (G4138A) to investigate the transcript level changes in rice leaf tissues during drought stress. We used two contrasting rice genotypes (IR64 drought susceptible and Apo drought tolerant) differing in their degree of drought tolerance. Plants were grown under green house conditions and drought stress was imposed on 33rd DAS. Leaf sampling was done in both control and drought stressed plants after 6 days of drought stress. Three replications of microarray experiments were carried out by hybridizing the control samples against the drought stressed samples.
Project description:Rice (Oryza sativa), the major staple food crop is being cultivated under varying ecosystems ranging from irrigated lowland to rainfed upland environments. Improvement in the rice production under drought prone unfavourable environment depends on the development of drought tolerant genotypes which needs thorough understanding of physiological and molecular events behind the tolerance mechanism. There is considerable genetic variation for drought tolerance mechanism within the cultivated gene pool. To understand the diversity of drought response, two indica rice genotypes namely, i) Apo, an up-land drought tolerant indica veriety from Philippines and ii) IR64, a popular high yielding drought susceptible genotype were selected for this study. We used the 22K rice Oligoarray from Agilent technologies to study the transcript profile in the leaves of the two contrasting rice genotypes under control and drought stressed conditions during vegetative phase. Keywords: Drought response
Project description:Background: Drought stress is the major environmental stress that affects plant growth and productivity. It triggers in plants a wide range of responses detectable at different scales: molecular, biochemical and physiological levels. At the molecular level the response to drought stress results in the differential expression of several metabolic pathways. For this reason, explore the subtle differences existing in gene expression of drought sensitive and drought tolerant genotypes allows to identify drought-related genes that could be used for selection of drought tolerance traits. Genome-wide RNA-Seq technology was used to compare the drought response of two sorghum genotypes characterized by contrasting water use efficiency. Results: the physiological measurements carried out confirmed the drought sensitivity of IS20351 and the drought tolerance of IS22330 previously studied. The expression of drought-related genes was more abundant in the sensitive genotype IS20351 compared to the tolerant IS22330. The Gene Ontology enrichment highlighted a massive increase in transcript abundance in “response to stress” and “abiotic stimulus”, “oxidation-reduction reaction” in the sensitive genotype IS20351 under drought stress. “Antioxidant” and “secondary metabolism”, “photosynthesis and carbon fixation process”, “lipids” and “carbon metabolism” were the pathways most affected by drought in the sensitive genotype IS20351. The sensitive genotype IS20351 showed under well-watered conditions a lower constitutive expression level of “secondary metabolic process” (GO:0019748) and “glutathione transferase activity” (GO:000004364). Conclusions: RNA-Seq analysis revealed to be a very useful tool to explore differences between sensitive and tolerant sorghum genotypes. The transcriptomic results supported all the physiological measurements and were crucial to clarify the tolerance of the two genotypes studied. The connection between the differential gene expression and the physiological response to drought states unequivocally the drought tolerance of the genotype IS22330 and the strategy adopted to cope with drought stress.
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.
Project description:Roots are generally the critical drought sensors, but little is known about their molecular response to drought stress. We used the drought-tolerant soybean variety ‘Jiyu 47’ to investigate the differentially expressed proteins (DEPs) in soybean roots during the seedling stage based on the TMT proteomics analysis. Results of enrichment analyses based on a total of 468 DEPs revealed a coordinated expression pattern of proteins involved in various cellular metabolisms responding to drought stress in soybean roots. Our results showed that drought stress caused significant alterations in the expression of proteins involved in several metabolic pathways in soybean roots, including the carbohydrate metabolism, the metabolism of the osmotic regulation substances, and the antioxidant defense system (i.e., the glutathione metabolism). Increased production of reduced glutathione (GSH) enhanced the prevention of the damage caused by reactive oxygen species and the tolerance of the abiotic stress. The glutathione metabolism played a key role in modifying the antioxidant defense system in response to drought stress in soybean roots. Our proteomic study demonstrated that the soybean plants responded to drought stress by coordinating their protein expression during the vegetative stage, providing novel insights into the molecular mechanisms regulating the response to abiotic stress in plants.
Project description:This study was aimed to deal with a comparative proteome analysis of the two chickpea genotypes with contrasting response to drought stress, ICC 4958 (drought-tolerant, DT) and ICC 1882 (drought-sensitive, DS). Proteins were extracted from the root tissues collected from the control and drought stressed plants of both the genotypes. NanoLC-MS/MS analysis of the protein sample was performed using EASY-nLC 1000 system for the separation and identification of peptides/proteins. This study provided a mechanistic insight of drought stress tolerance in chickpea.
Project description:Comparative analysis of transcriptome in two wheat genotypes with contrasting levels of draught tolerance. We used microarrays to investigate the global gene expression in response to drought stress.
Project description:A customized targeted oligoarray was used to monitor the expression levels of 1000 genes, representative of the immature kernel transcriptome. Using this oligoarray we compared transcripts from 10 DAP kernels of two susceptible and two drought tolerant genotypes. These four genotypes were extracted from our RIL population (B73xH99) and grown under water stress and well watered field conditions. Keywords: Stress response
Project description:Comparative transcriptional profiling of two contrasting rice genotypes,IRAT109 (drought-resistant japonica cultivar) and ZS97 (drought-sensitive indica cultivar), under drought stress during the reproductive stage