Project description:Closely related lineages can possess phenotypic variation important for adaptation and the evolution of new species; a phenomenon that can be more clearly elucidated by studying hybrid generations. We compare variation in gene expression in response to drought for two taxa and advanced-generation hybrids of the Piriqueta cistoides ssp. caroliniana complex that differ in their levels of tolerance to water limitation. Drought treatments lasted 36 days, through four cycles of drought. Gene expression in drought and control treatments was assessed using heterologous hybridization to a Glycine max microarray. There was a predominance of down-regulated genes in response to sustained drought in all morphotypes. This pattern was more pronounced in the hybrids, which can exhibit greater drought tolerance under field and greenhouse conditions than the parental morphotypes. Expression response profiles were more similar between the hybrid and the drought-tolerant parental morphotype than they were between the hybrid and the parental morphotype that occurs in more mesic habitats. Predominant down-regulation of gene expression contrasts with studies of response to short-term drought and with studies of drought-response in annual and non-drought-tolerant model species, and supports the results of a growing number of studies with other drought-tolerant perennial plants under prolonged drought.
Project description:Closely related lineages can possess phenotypic variation important for adaptation and the evolution of new species; a phenomenon that can be more clearly elucidated by studying hybrid generations. We compare variation in gene expression in response to drought for two taxa and advanced-generation hybrids of the Piriqueta cistoides ssp. caroliniana complex that differ in their levels of tolerance to water limitation. Drought treatments lasted 36 days, through four cycles of drought. Gene expression in drought and control treatments was assessed using heterologous hybridization to a Glycine max microarray. There was a predominance of down-regulated genes in response to sustained drought in all morphotypes. This pattern was more pronounced in the hybrids, which can exhibit greater drought tolerance under field and greenhouse conditions than the parental morphotypes. Expression response profiles were more similar between the hybrid and the drought-tolerant parental morphotype than they were between the hybrid and the parental morphotype that occurs in more mesic habitats. Predominant down-regulation of gene expression contrasts with studies of response to short-term drought and with studies of drought-response in annual and non-drought-tolerant model species, and supports the results of a growing number of studies with other drought-tolerant perennial plants under prolonged drought. A total of 18 array hyridizations. Two conditions (drought and control), three morphotypes (caroliniana, viridis, and hybrid), for a total of 6 morphotype/treatment combinations. Three samples of each morphotypes/treatment combination were hybridized twice in dye swap in a loop design.
Project description:comprehensive and quantitative proteomic study of the roots of the NH4+-tolerant legume Medicago truncatula grown with nitrate, NH4+ or urea as sole N source using the iTRAQ method.
Project description:Lotus japonicus is a perennial legume with a small diploid genome that has been adopted as a model species for legume genetics and genomics. With the genome sequence as a backdrop (Sato et al. 2008), we have generated a gene expression atlas that provides a global view of gene expression in all major organ systems of this species, including nodule and seed development.
Project description:This study was designed to determine the effects of plant derived compounds on the transcriptome of estrogen receptor positive breast cancer. Phytoestrogens are compounds produced by plants that possess weak estrogenic activity. They can be found in a wide variety of plants, including fruits and vegetables, but are most abundant in leguminous plants. Legumes are consumed in almost every diet throughout the world, and in addition to the seeds, many other parts of the plant are also edible, including the pods of some varieties. Soybeans have been demonstrated to contain high concentrations of the isoflavones daidzein and genistein, which are re-sponsible for many of the health benefits of soy. Besides isoflavonoids, flavonoids also exert estrogenic activity, but usually at a much lower level of activity compared to that of isoflavonoids. Also, some flavonoids, including kaempferol and quercetin, canexhibit antiestrogenic activity, with several legumes being a source of these flavo-noids. Coumestrol, a coumestan with high estrogenic activity in cell and animal as-says, is also present in several legume seeds and sprouts. These underutilized plant compounds could hold previously unknown potential for antioxidant activity, anti-inflammation activity, cholesterol lowering ability, and even anticancer activity. The goal of the present study was to identify the effects of plant derived compounds on estrogen receptor positive cell line to determine if the compound possess estrogenic or anti-estrogenic activity, thereby highlighting potential implications on human health through diet.
Project description:Genome-wide Transcriptional Analysis of Genes Associated with Drought Stress in Gossypium herbaceum root This experiment was designed to investigate the molecular mechanism associated with drought tolerance in root tissue of Gossypium herbaceum. The gene expression profiles of the root tissue using Affymetrix Cotton Genome Array were compared with drought tolerant and drought sensitive genotype of G.herbaceum under drought stress and watered condition. Many genes in various molecular function or biological processes were over- or under-represented between drought tolerant and sensitive genotype, suggesting various molecular mechanism and biochemical pathways are interlinked and tolerant genotype have developed multiple mechanisms as an adaptory behavior against drought stress.
Project description:Drought often compromises yield in non-irrigated crops such as rainfed rice, imperiling the communities that depend upon it as a primary food source. In this study, two cultivated species (Oryza sativa cv. Nipponbare and Oryza glaberrima cv. CG14) and an endemic, perennial Australian wild species (Oryza australiensis) were grown in soil at 40% field capacity for 7-d (drought). The hypothesis was that the natural tolerance of O. australiensis to erratic water supply would be reflected in a unique proteomic profile. Leaves from droughted plants and well-watered controls were harvested for label-free quantitative shotgun proteomics. Physiological and gene ontology analysis confirmed that O. australiensis is responded uniquely to drought, with superior leaf water status and enhanced levels of photosynthetic proteins. Moreover, distinctive patterns of expression of proteins in drought were observed across the entire O. australiensis proteome. An intermediate impact of drought on photosynthetic and stress-response proteins is reported in O. glaberrima relative to O. sativa but the drought response was most striking in O. australiensis. For example, photosynthetic proteins decreased when O. sativa after drought, while a narrower range of stress-responsive proteins was up-regulated. Distinctive proteomic profiles and the expression levels of individual proteins with specific functions in response to drought in O. australiensis indicate the importance of this species as a source of stress tolerance genes.
Project description:With climate change, droughts are expected to be more frequent and severe, severely impacting plant biomass and quality. Here, we show that overexpressing the Arabidopsis gene AtFtsHi3 (FtsHi3OE) enhances drought-tolerant phenotypes without compromising plant growth. AtFtsHi3 encodes a chloroplast envelope pseudo-protease; knock-down mutants (ftshi3-1) are found to be drought tolerant but exhibit stunted growth. Altered AtFtsHi3 expression therefore leads to drought tolerance, while only diminished expression of this gene leads to growth retardation. To understand the underlying mechanisms of the enhanced drought tolerance, we compared the proteomes of ftshi3-1 and pFtsHi3-FtsHi3OE (pFtsHi3-OE) to wild-type plants under well-watered and drought conditions. Drought-related processes like osmotic stress, water transport, and abscisic acid response were enriched in pFtsHi3-OE and ftshi3-1 mutants following their enhanced drought response compared to wild-type. The knock-down mutant ftshi3-1 showed an increased abundance of HSP90, HSP93, and TIC110 proteins, hinting at a potential downstream role of AtFtsHi3 in chloroplast pre-protein import. Mathematical modeling was performed to understand how variation in the transcript abundance of AtFtsHi3 can, on the one hand, lead to drought tolerance in both overexpression and knock-down lines, yet, on the other hand, affect plant growth so differently. The results led us to hypothesize that AtFtsHi3 may form complexes with at least two other protease subunits, either as homo- or heteromeric structures. Enriched amounts of AtFtsH7/9, AtFtsH11, AtFtsH12, and AtFtsHi4 in ftshi3-1 suggest a possible compensation mechanism for these proteases in the hexamer.
Project description:Leaf samples were used. We exposed young seedlings to NaCl and drought. Expression study in 24hrs salt and drought condition. Salt-sensitive and salt-tolerant strains of rice exposed to NaCl or control conditions. Drought-sensitive and drought-tolerant strains of rice exposed to drought or control conditions.
Project description:Switchgrass (Panicum virgatum) is a perennial crop producing deep roots thus highly tolerant to soil water deficit conditions. However, seedling establishment in field is very susceptible to prolonged and periodic drought stress. In this study, a “sandwich” system simulating a gradual water deletion process was developed. Switchgrass seedlings were subjected to a 20-day gradual drought treatment process when soil water tension was increased to 0.05 MPa (moderate drought stress) and leaf physiological properties had expressed significant alteration. Drought-induced changes in leaf proteomes were identified using the relative and absolute quantitation (iTRAQ) labeling method followed by nano-scale liquid chromatography mass spectrometry (nano-LC-MS/MS) analysis. Additionally, total leaf proteins were processed using a combinatorial library of peptide ligands to enrich for lower abundance proteins. Both total proteins and those enriched samples were analyzed to increase the coverage of the quantitative proteomics analysis. A total of 7,006 leaf proteins were identified, and 257 (4% of the leaf proteome) expressed a significant difference (P < 0.05, fold change < 0.6 or > 1.7) from the non-treated control to drought-treated conditions. Results from this study, in addition to revealing molecular responses to drought stress, provide a large number of proteins (candidate genes) that can be employed to improve switchgrass seedling growth and establishment under soil drought condition.