Project description:Global gene expression was compared between roots of cotton plants (variety Sicot 71) flooded for 4 hours and roots of unflooded cotton plants. Global gene expression was also compared between leaves of cotton plants (variety Sicot 71) flooded for 24 hours and leaves of unflooded cotton plants. Waterlogging stress causes yield reductions in cotton (Gossypium hirsutum L.). A major component of waterlogging stress is the lack of oxygen available to submerged tissues. While changes in expressed protein, gene transcription and metabolite levels have been studied in response to low oxygen stress, little research has been done on molecular responses to waterlogging in cotton. We assessed cotton growth responses to waterlogging and assayed global gene transcription responses in root and leaf cotton tissues of partially submerged plants. Waterlogging causes significant reductions in stem elongation, shoot mass, root mass, and leaf number. At the global gene expression level waterlogging significantly alters the expression of 1012 genes (4.2% of genes assayed) in root tissue as early as 4h after flooding. Many of these genes are associated with cell wall modification and growth pathways, glycolysis, fermentation, mitochondrial electron transport and nitrogen metabolism. Waterlogging of plant roots also altered global leaf gene expression, significantly changing the expression of 1305 genes (5.4% of genes assayed) after 24h of flooding. Genes associated with cell wall growth and modification, tetrapyrrole synthesis, hormone response, starch metabolism and nitrogen metabolism were affected in leaf tissues of waterlogged plants. Implications of these results for the development of waterlogging tolerant cotton are discussed. Keywords: Stress Response Plants of cotton cultivar Sicot 71 were grown to the two-leaf stage in tubs. For stress treatments plants were either watered as normal or flooded with water to completely submerge the root system. At four and twenty-four hours post-flooding samples of root or leaf tissue were taken from control and flooded plants. Total RNA was extracted from each tissue sample and assayed on cotton Affymetrix chips. Two biological replications were used for each comparison.
Project description:Cotton seedlings were subjected to water-deficit stress along with control condition for 24 hours or 48 hours and tissues emcompassing the elongation zone of primary roots were analysed for differential accumulated transcripts compared to control.
Project description:Cotton (Gossypium hirsutum L.) is one of the most important cash crops worldwide. In semi-arid/arid regions, drought stress causes growth limitation and decrease of yield. Of all the organs of a plant, fine root is the central part consisting of the root system to contribute to plant water and nutrient taken up. However, the research on the molecular mechanism underlying fine root response to soil drought has not been well understood in cotton. To better characterize the proteomic changes of cotton fine roots under drought stress, 70±5% and 40±5% soil relative water content were designed as control (CK) and drought stress (DS) groups, respectively. Tandem mass tags (TMT) technology was used to determine the proteome profiles in fine roots. The proteomic differences between CK and DS were pairwise compared at 0, 30, and 45 days after drought stress (DAD). A total of 11,628 proteins were identified, of which 10,344 proteins contained quantitative information. According to the morphological, physiological, and biochemical characteristics, 30 and 45 DAD were selected as critical stages for further analysis. Results showed that 118 differentially expressed proteins (DEPs) were up-regulated and 105 down-regulated in DS 30 versus CK 30; 662 DEPs were up-regulated, and 611 were down-regulated in DS 45 versus CK 45. The DEP functions were determined for their classified pathways, mainly associated with carbohydrate metabolism, energy metabolism, fatty acid metabolism, amino acid metabolism, and secondary metabolite biosynthesis. DEPs related to phytohormone and stress/defense response were also identified. To verify the accuracy of the TMT results, 20 DEPs were randomly selected for parallel reaction monitoring (PRM) verification. And results showed that the quantitative results of TMT are consistent with those of PRM, which proved that the TMT results of this study are reliable. In this article we describe changes in the protein profiles occurring in response to drought stress in cotton fine roots. Proteomic analyses of plant responses to stressors could lead to the introduction of cotton cultivars with high resistance to drought stress. Such plants would be valuable for high yielding under drought as well as other unfavorable environmental conditions.
Project description:Cotton productivity is affected by water deficit and little is known about the molecular basis of drought tolerance in cotton. In this study, microarray analysis was carried out to identify drought responsive genes in functional leaves of the field-grown drought stressed cotton (Gossypium hirsutum L.) Acala 1517-99. The water stress was imposed after withholding irrigation for 9 days in the early squaring stage, which resulted in 10-15% reduction in plant growth compared to the well watered plants. A total of 110 drought responsive genes (0.5% of the total genes represented in the microarray) were identified, 79% (88 genes) of which were down-regulated and 21% (22 genes) were up-regulated by water stress. The responsiveness of 19 selected drought responsive genes was validated by real time PCR. The drought inducible genes were grouped into six functional categories only including stress related (10 genes, 9 of which are heat shock proteins), metabolism (3) and one each for transcription factor, proline biosynthesis and cellular transport. The down-regulated genes were classified into 14 functional categories including metabolism (20 genes), cellular transport (12), stress related (12), and regulation of gene expression (9) and transcription factor (4), signal transduction (7) and 2 genes each for biosynthesis of secondary compounds, cell wall, fatty acids/lipids and chlorophyll, and protein degradation. Most of the genes have been reported in other plants as drought tolerant/responsive and only 21 drought responsive genes (19%) were functionally unknown. The genes identified provides the first glimpse into the molecular basis of drought response in cotton.
Project description:Structural and functional approaches were used to study cotton (Gossypium) genes implicated in water-deficit stress. A genetic map representing the hypothetical ancestral diploid genome (Consensus Map) was used to map 1,907 of 15,784 tentative consensus sequences (TCs). These TCs represent 25,119 cotton ESTs derived from various tissues under irrigated and water-limited condition. The correspondence of mapped TCs and 42 stress-related quantitative trait loci (QTLs) revealed that 391 of the initial 1907 TCs co-localized within a QTL interval. About 31% of these TCs were annotated as genes involved in plant responses to abiotic stress. By comparison, only 18% of the total annotated TCs mapped on the Consensus map were classified as abiotic stress genes. The enrichment of stress-related TCs that map to stress-related QTLs could not be explained by chance (P = 1.5 x 10-7). Gene expression profiling experiments were carried out using a microarray composed of 12,006 oligonucleotides. Transcriptional responses to imposed water-deficit stress in root and leaf tissue of 8-week old cotton plants revealed 1401 transcripts identified as drought responsive. A total of 158 (84 drought-induced and 74 drought-repressed) genes were mapped, of which 22 (8 induced and 14 repressed) genes co-localized with a QTL. A total of 539 unique genes were identified in the drought-stressed libraries. However, only 91 of these genes are contained on the array. Of these genes, 12 showed significant changes in transcript abundance between stressed and irrigated leaf and root. Forty-five candidate genes implicated in drought-stress response at some level of characterization were identified. Keywords: stress response
Project description:Cotton premature leaf senescence often occurred with an increasing frequency in many cotton growing areas and caused serious reduction in yield and quality of cotton has been one of the impontant factors that restrict severely the production of cotton.Our laboratory studies showed chilling stress is the key factor that induced A. alternatia infection, caused Alternaria disease and then lead to cotton leaf senescence, but the molecular mechanism of cotton premature leaf senscence is still unclear. We used microarrays to study molecular mechanism of chilling stress causing Alternaria alternata infection and leading to cotton leaf senescence and find the key genes during this process. Plants were grown in growth chamber with a 14/10 hours photoperiod, 28â/22â. Three-to-four leaves stage cotton plants were pre-treated by chilling stress with the low temperatures of 16/12â day/night for a fixed time length of 3 days. While, the normal growth plants were sustained growing at optimal temperature of 28/20â day/night. And then, both chilling stress pre-treated and normal growth cotton plants were inoculated with Alternaria. alternata isolate A1. The mock inoculations were performed with sterilized water. Cotton leaf Samples were respectively collected at 3, 6 days after inoculation (DAI) for RNA extraction and hybridization on Affymetrix microarrays. To that end, we collected 8 samples, i.e. chilling stress pre-treated cotton leaves: 3 DAI (C) and its mock control (D), 6 DAI (E) and its mock control (F); normal growth cotton leaves: 3 DAI (H) and its mock control (I), 6 DAI (J) and its mock control (K). All samples were arranged in completely randomized designed with three replications for each treatment.
Project description:To explore the mechanisms of cotton response to Na2SO4 stress, we used next-generation sequencing (NGS) technology to study transcriptional changes of cotton under the treatment of 300 mmol• L-1 Na2SO4 solution at 12 h and the control with water at 12 h. A total of 15,524, 20,409 and 12,146 differentially expressed genes (DEGs) were identified in cotton roots, stems and leaves between treatment and control, respectively. Gene ontology (GO) analysis indicated the enrichment of DEGs involved in various stimuli or stress responses. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed that DEGs associated with plant hormone signal transduction, plant-pathogen interaction, and Starch and sucrose metabolites were regulated in response to the Na2SO4 stress. We further analyzed genes enriched in ROS (reactive oxygen species) scavenging system including osmotic stress and ion toxicity were significantly up-regulated. In addition, analysis for sulfur metabolism, results in to identification of two rate limiting enzymes APR and OASTL during synthesis of GSH from SO42-. The analysis of the expression profiles of diverse tissues under Na2SO4 stress and identification of relevant key hub genes in a network crosstalk will provide a strong foundation and valuable clues for genetic improvements of cotton in response to various salt stresses.
Project description:Comparative transcriptome profiles of cotton (G. hirsutum L. cv. Bikaneri narma) during boll development stages (0, 2, 5 and 10 dpa) under bollworm infested biotic stress. Cotton is one of the most commercially important fibre crops in the world and used as a source for natural textile fibre and cottonseed oil. The biotic stress is one of the major constraints for crop production. Cotton bollworm (Helicoverpa armigera) is one the major insect pest in cotton and drastically damages the cotton boll. To decipher the molecular mechanisms involved in cotton boll/fibre cell development, transcriptome analysis has been carried out by comparing G. hirsutum L cv. Bikaneri narma cotton boll samples induced by biotic stress (bollworm infested) and that their respective control cotton bolls collected under field conditions. Cotton bolls were collected at fibre initiation (0, 2 dpa/days post anthesis) and elongation (5, 10 dpa) stages for both control and biotic stress condition and gene expression profiles were analyzed by Affymetrix cotton GeneChip Genome array.
Project description:Global gene expression was compared between roots of cotton plants (variety Sicot 71) flooded for 4 hours and roots of unflooded cotton plants. Global gene expression was also compared between leaves of cotton plants (variety Sicot 71) flooded for 24 hours and leaves of unflooded cotton plants. Waterlogging stress causes yield reductions in cotton (Gossypium hirsutum L.). A major component of waterlogging stress is the lack of oxygen available to submerged tissues. While changes in expressed protein, gene transcription and metabolite levels have been studied in response to low oxygen stress, little research has been done on molecular responses to waterlogging in cotton. We assessed cotton growth responses to waterlogging and assayed global gene transcription responses in root and leaf cotton tissues of partially submerged plants. Waterlogging causes significant reductions in stem elongation, shoot mass, root mass, and leaf number. At the global gene expression level waterlogging significantly alters the expression of 1012 genes (4.2% of genes assayed) in root tissue as early as 4h after flooding. Many of these genes are associated with cell wall modification and growth pathways, glycolysis, fermentation, mitochondrial electron transport and nitrogen metabolism. Waterlogging of plant roots also altered global leaf gene expression, significantly changing the expression of 1305 genes (5.4% of genes assayed) after 24h of flooding. Genes associated with cell wall growth and modification, tetrapyrrole synthesis, hormone response, starch metabolism and nitrogen metabolism were affected in leaf tissues of waterlogged plants. Implications of these results for the development of waterlogging tolerant cotton are discussed. Keywords: Stress Response
Project description:Cotton premature leaf senescence often occurred with an increasing frequency in many cotton growing areas and caused serious reduction in yield and quality of cotton has been one of the impontant factors that restrict severely the production of cotton.Our laboratory studies showed chilling stress is the key factor that induced A. alternatia infection, caused Alternaria disease and then lead to cotton leaf senescence, but the molecular mechanism of cotton premature leaf senscence is still unclear. We used microarrays to study molecular mechanism of chilling stress causing Alternaria alternata infection and leading to cotton leaf senescence and find the key genes during this process.