Project description:In this study we employ a strand-specific RNA-seq appoach and stranded gene expression analysis tools to identify drought responsive antisense gene loci and sense-antisense gene pairs in Populus. we generated and sequenced 28 strand-specific cDNA libraries derived from either leaf or root tissues of Populus trichocarpa plants associaed with both short-term drought (24 hours of water stress of 40% of field capacity) and long-term drought ( 25 days of water stress of 40% of field capacity) . We mapped over 71 billion nucleotides to Populus genome. Our data demonstrates that with the current sequence depth ~ 19 % of Populus genome undergoes antisense transcription subjected to drought regulation. All in all we have identified that in root tissues 524 differentially expressed antisense genes and 247 drought-responsive SA gene pairs which are significantly regulated by drought (padj <0.05). Taken all data from both drought treatments, we have identified 1185 unique drought-responsive antisense gene loci and 606 drought-responsive SA gene pairs (padj <0.05).
Project description:Populus deltoides and Populus trichocarpa were exposed to either ambient air or an acute ozone exposure of 200 ppb for 9 hrs and ozone response was profiled for each genotype by hybridising control against ozone-exposed samples per genotype. Keywords: stress response, genotype comparrison, ozone exposure
Project description:We sequenced mRNA from the control and heat treatments leaves of Populus tomentosa using the Illumina HiSeq4000 platform to generate the transcriptome dynamics that may serve as a gene expression profile blueprint for different response patterns under control and heat stress in Populus tomentosa.
Project description:DNA methylation is an important biological form of epigenetic modification, playing key roles in plant development and environmental responses. In this study, we examined single-base resolution methylomes of Populus under control and drought stress conditions using high-throughput bisulfite sequencing for the first time. Our data showed methylation levels of methylated cytosines, upstream2kp, downstream2kb, and repeatitive sequences significantly increased after drought treatment in Populus. Interestingly, methylation in 100 bp upstream of the transcriptional start site (TSS) repressed gene expression, while methylations in 100 – 2000bp upstream of TSS and within the gene body were positively associated with gene expression. Integrated with the transcriptomic data, we found that all cis-splicing genes were non-methylated, suggesting that DNA methylation may not associate with cis-splicing. However, our results showed that 80% of trans-splicing genes were methylated. Moreover, we found 1156 transcription factors (TFs) with reduced methylation and expression levels and 690 TFs with increased methylation and expression levels after drought treatment. These TFs may play important roles in Populus drought stress responses through the changes of DNA methylation. Taken together, these findings may provide valuable new insight into our understanding of the interaction between gene expression and methylation of drought responses in Populus. Methylomes of Poplar response to drought
Project description:We report on the genome-wide distribution pattern of histone H3 lysine 9 acetylation (H3K9ac) and the pattern’s association with whole genome expression profiles in Populus trichocarpa subjected to soil-water depletion. We identified a set of drought responsive genes whose expression is directly regulated by differential modification of H3K9ac.
Project description:DNA methylation is an important biological form of epigenetic modification, playing key roles in plant development and environmental responses. In this study, we examined single-base resolution methylomes of Populus under control and drought stress conditions using high-throughput bisulfite sequencing for the first time. Our data showed methylation levels of methylated cytosines, upstream2kp, downstream2kb, and repeatitive sequences significantly increased after drought treatment in Populus. Interestingly, methylation in 100 bp upstream of the transcriptional start site (TSS) repressed gene expression, while methylations in 100 – 2000bp upstream of TSS and within the gene body were positively associated with gene expression. Integrated with the transcriptomic data, we found that all cis-splicing genes were non-methylated, suggesting that DNA methylation may not associate with cis-splicing. However, our results showed that 80% of trans-splicing genes were methylated. Moreover, we found 1156 transcription factors (TFs) with reduced methylation and expression levels and 690 TFs with increased methylation and expression levels after drought treatment. These TFs may play important roles in Populus drought stress responses through the changes of DNA methylation. Taken together, these findings may provide valuable new insight into our understanding of the interaction between gene expression and methylation of drought responses in Populus.
Project description:We present an efficient method to genome-wide discover new and drought stress responsive miRNAs in P. euphratica. High throughput sequencing of P. euphratica leaves found 197 conserved miRNAs between P. euphratica and Populus trichocarpa. Meanwhile, 189 new miRNAs which belonged to 120 families were identified, a large increasing to the number of P. euphratica miRNAs. Target prediction and degradome sequencing verification of 22 new and 21 conserved miRNA targets showed these targets were involved in multiple biological processes, including transcription regulation and response to stimulus. Furthermore, comparison of high-throughput sequencing with miRNA microarray profiling data indicated that 104 miRNA sequences were up-regulated, while 27 were down-regulated under drought stress. This preliminary characterization based on our findings provided a framework for future analysis of miRNA genes and their roles in key traits of poplar as stress resistance plant breeding and environment protection usage.
Project description:We present an efficient method to genome-wide discover new and drought stress responsive miRNAs in P. euphratica. High throughput sequencing of P. euphratica leaves found 197 conserved miRNAs between P. euphratica and Populus trichocarpa. Meanwhile, 189 new miRNAs which belonged to 120 families were identified, a large increasing to the number of P. euphratica miRNAs. Target prediction and degradome sequencing verification of 22 new and 21 conserved miRNA targets showed these targets were involved in multiple biological processes, including transcription regulation and response to stimulus. Furthermore, comparison of high-throughput sequencing with miRNA microarray profiling data indicated that 104 miRNA sequences were up-regulated, while 27 were down-regulated under drought stress. This preliminary characterization based on our findings provided a framework for future analysis of miRNA genes and their roles in key traits of poplar as stress resistance plant breeding and environment protection usage. Examination of sRNA expression in 2 poplar leaf samples in drought and normal growth conditions.