Project description:MicroRNAs (miRNAs) are part of gene regulatory networks that direct all most all biological processes in plants including their growth and development, as well as adaptation to biotic and abiotic stresses. Sorghum is largely grown for its grain production, but recently it also emerged a major feedstock for biofuel production. Interestingly, Sorghum is relatively drought tolerant crop and largely grown in semi-arid tropical and sub-tropical regions where the drought or high temperature or their combination co-occur in the field. Although miRNA profiles have been reported in Sorghum leaves exposed to drought, but thus far miRNAs in heat- or drought and heat-exposed conditions have not been reported. In this study, we report miRNA profiles in Sorghum leaves exposed to drought or heat or their combination. The bioinformatic analysis of small RNA libraries revealed the expression of approximately 30 conserved miRNA families represented by 81 individual miRNAs as well as 11 novel miRNA families in Sorghum leaves. Of these, 26 miRNAs were found to be differentially regulated in response to one or more of the stress treatments. Overall, the number of miRNAs regulated by heat was more than the drought. Furthermore, miRNA profiles revealed more similarities between heat and the combination of drought and heat stresses. We also have analyzed degradome profiles in control and drought-exposed plants to identify potential targets for the miRNAs. This study provides a frame work for better understanding of miRNA-guided gene regulations that vary between individual drought or heat or combination of drought and heat treatments.
Project description:MicroRNAs (miRNAs) are part of gene regulatory networks that direct all most all biological processes in plants including their growth and development, as well as adaptation to biotic and abiotic stresses. Sorghum is largely grown for its grain production, but recently it also emerged a major feedstock for biofuel production. Interestingly, Sorghum is relatively drought tolerant crop and largely grown in semi-arid tropical and sub-tropical regions where the drought or high temperature or their combination co-occur in the field. Although miRNA profiles have been reported in Sorghum leaves exposed to drought, but thus far miRNAs in heat- or drought and heat-exposed conditions have not been reported. In this study, we report miRNA profiles in Sorghum leaves exposed to drought or heat or their combination. The bioinformatic analysis of small RNA libraries revealed the expression of approximately 30 conserved miRNA families represented by 81 individual miRNAs as well as 11 novel miRNA families in Sorghum leaves. Of these, 26 miRNAs were found to be differentially regulated in response to one or more of the stress treatments. Overall, the number of miRNAs regulated by heat was more than the drought. Furthermore, miRNA profiles revealed more similarities between heat and the combination of drought and heat stresses. We also have analyzed degradome profiles in control and drought-exposed plants to identify potential targets for the miRNAs. This study provides a frame work for better understanding of miRNA-guided gene regulations that vary between individual drought or heat or combination of drought and heat treatments.
Project description:Purpose: Circular RNAs (circRNAs) and microRNAs (miRNAs) play important roles in abiotic stress responses in plants. The aims of this study are to genome-widely identify the circRNAs, miRNAs and their targets in tomatoes at single heat, drought and their combination by high-throughput sequencing. Results: Following high-throughput sequencing, 765 miRNAs were identified in total with 335 conserved and 430 novel miRNAs in the 12 small-RNA libraries. Of these miRNAs, 32, 74 and 61 miRNAs were responsive to drought, heat and their combination, respectively. Following degradome sequencing, 50 sequences were identified as targets of 34 miRNAs in tomatoes at combined stress. Moreover, 467 circRNAs were identified in the 12 samples.
Project description:One of the eminent opportunities afforded by modern genomic technologies is the potential to provide a mechanistic understanding of the processes by which genetic change translates to phenotypic variation and the resultant appearance of distinct physiological traits. Indeed much progress has been made in this area, particularly in biomedicine where functional genomic information can be used to determine the physiological state (e.g., diagnosis) and predict phenotypic outcome (e.g., patient survival). Until now, ecology has lacked an analogous approach where genomic information can be used to diagnose the presence of a given physiological state (e.g., stress response) and then predict likely phenotypic outcomes (e.g., stress tolerance, fitness). We demonstrate that a compendium of genomic signatures can be used to classify the plant abiotic stress phenotype in Arabidopsis according to the architecture of the transcriptome, and then be linked with gene coexpression network analysis to determine the underlying signaling pathways and ultimately the genes governing the phenotypic response. Here, we release microarray data from an expression profiling study where plants were exposed to heat and drought alone, and in combination with each other. A direct loop design with 6 biological replicates for control, heat, drought, and combined heat and drought was performed. A schematic describing the design is provide as supplementary information.
Project description:One of the eminent opportunities afforded by modern genomic technologies is the potential to provide a mechanistic understanding of the processes by which genetic change translates to phenotypic variation and the resultant appearance of distinct physiological traits. Indeed much progress has been made in this area, particularly in biomedicine where functional genomic information can be used to determine the physiological state (e.g., diagnosis) and predict phenotypic outcome (e.g., patient survival). Until now, ecology has lacked an analogous approach where genomic information can be used to diagnose the presence of a given physiological state (e.g., stress response) and then predict likely phenotypic outcomes (e.g., stress tolerance, fitness). We demonstrate that a compendium of genomic signatures can be used to classify the plant abiotic stress phenotype in Arabidopsis according to the architecture of the transcriptome, and then be linked with gene coexpression network analysis to determine the underlying signaling pathways and ultimately the genes governing the phenotypic response. Here, we release microarray data from an expression profiling study where plants were exposed to heat and drought alone, and in combination with each other. Keywords: Stress response, heat, drought, combined stress
Project description:Sorghum is an important crop often subjected to simultaneous high temperatures and drought in the field. We examined the gene expression response to heat and drought stress both individually, and in combination, with the aim of identifying important stress tolerance mechanisms. Plants were subjected to 4 different conditions (control, heat shock, drought stress and combined heat and drought stress). 3 replicates were carried out for each treatment type giving a total of 12 samples
Project description:Purpose: Increasing biomass yield and quality of feedstock have been a recent interest in switchgrass research. Despite the economic importance of switchgrass, increasing temperature and water deficit are limiting factors to the cultivation of bioenergy crops in the semi-arid areas. The effect of individual drought or heat stress has been studied separately in switchgrass. However, there is relatively limited or no report on the molecular basis of combined abiotic stress tolerance in switchgrass particularly the combination of drought and heat stress. We used RNA-Seq approaches to elucidate the transcriptome changes of switchgrass in response to drought and high temperatures simultaneously. Method: We conducted solely drought treatment in switchgrass plant Alamo AP13 by withholding water after 45 days of growing. For the combination of drought and heat effect, heat treatment (35 °C/25 °C day/night) was imposed after 72 h of the initiation of drought. Samples were collected at 0 h, 72 h, 96 h, 120 h, 144 h, and 168 h after treatment imposition, total RNA was extracted, and RNA-Seq conducted. Results:Out of total 32,190 genes, we identified 3,912, as DT responsive genes, 2,339 and 4,635 as , heat (HT) and drought and heat (DTHT) responsive genes, respectively. There were 209, 106, and 220 transcription factors (TFs) differentially expressed under DT, HT and DTHT respectively Conclusion: Through RNA-Seq analysis, we have identified unique and overlapping genes in response to DT and combined DTHT stress in switchgrass. The combination of DT and HT stress may affect the photosynthetic machinery and phenylpropanoid pathway of switchgrass which negatively impacts lignin synthesis and biomass production of switchgrass. The biological function of genes identified particularly in response to DTHT stress could further be confirmed by techniques such as single point mutation or RNAi.