Project description:The present study is expected to reveal regulatory network of small RNAs under drought in Sorghum (Sorghum bicolor (L.) Moench). Sorghum genotype drought tolerant (DT) and drought susceptible (DS) were grown at 28-32 degrees C day/night temperature with 12/12 h light/dark period in the phytotron glass house. The fully opened uppermost leaves from control and drought stressed seedlings were sampled and stored at -80 degrees C, and used for generation of a small RNA library. Total RNA was isolated from the leaves using the TRIzol reagent (Invitrogen, USA). Small RNA sequencing libraries were prepared using Illumina Truseq small RNA Library preparation kit following manufacturer's protocol and these libraries were sequenced on GAIIx platform (Illumina Inc., USA). Small RNA reads contaminated with poor-quality and adaptor sequences were trimmed by using the UEA sRNA workbench 2.4- Plant version sequence file pre-processing (http://srna-tools.cmp.uea.ac.uk/). Then, all unique reads were submitted to the UEA sRNA toolkit-Plant version miRCat pipeline (http://srna-tools.cmp.uea.ac.uk/) to predict novel miRNAs from high-throughput small RNA sequencing data.
Project description:Flowering pathways are accelerated for rapid production of flowers and seeds in response to drought in certain varieties of sorghum (Sorghum bicolor (L.) Moench). The objective of the present study was to identify potential drought responsive genes that affect flowering time in sorghum under drought stress. Sorghum germplasm accessions representing early, intermediate, and late flowering groups were selected, and drought stress was administered on 25-day old seedlings of the Drought-Stressed group (DS) by withdrawing water whilst the control group of plants were well-watered (WW). At anthesis, with the initiation of pollen shedding, flag leaf tissues were harvested, and total RNA was separately isolated from samples. Transcription profiles consisting of 60 base pairs, paired end reads from total RNA of each sample were explored using Illumina Genome Analyzer deep sequencing method. An average of 66,059,932 clean reads were mapped. Among 10,468 differentially expressed genes, a set of 126 genes was up-regulated, and a set of 61 genes was down-regulated in all comparisons. Pathway enrichment analysis revealed de novo purine biosynthesis and lipoate biosynthesis pathways and Wnt signaling pathway affecting differentially expressed sorghum genes in response to drought. Transcriptome level differences among early, intermediate and late flowering groups of sorghum under WW and DS conditions were efficiently explored in the present study using RNA sequence analysis tools. Candidate genes and pathways that might be used to improve drought tolerance in sorghum were identified. Findings of the present study would lead to new targets for enhancing drought stress tolerance in sorghum.
Project description:Brassinosteroids (BRs) are a class of class of phytohormones with important roles in regulating physiological and developmental processes. Small RNAs, including small interfering RNAs and microRNAs (miRNAs), are non-protein coding RNAs that regulate gene expression at the transcriptional and post-transcriptional levels. However, the roles of small RNAs in BR response have not been studied well. In this study, we aimed to identify BR-responsive small RNA clusters and miRNAs in Arabidopsis. In addition, the effect of BR-responsive small RNAs on their transcripts and target genes were examined. Small RNA libraries were constructed from control and epibrassinolide-treated seedlings. After sequencing the small RNA libraries, differentially expressed small RNA clusters were identified by examining the expression levels of small RNAs in 100-nt bins of Arabidopsis genome. To identify the BR-responsive miRNAs, the expression levels of all the annotated mature miRNAs, registered in miRBase, were analyzed. Previously published RNA-seq data were utilized to monitor the BR-responsive expression patterns of differentially expressed small RNA clusters and miRNA target genes. In results, 38 BR-responsive small RNA clusters, including 30 down-regulated and eight up-regulated clusters, were identified. These differentially expressed small RNA clusters were from miRNA loci, transposons, protein-coding genes, pseudo genes and others. Of these, a transgene, BRI1, accumulates small RNAs, which are not found in the wild type. Small RNAs in this transgene are up-regulated by BRs while BRI1 mRNA is down-regulated by BRs. By analyzing the expression patterns of mature miRNAs, we have identified BR-repressed miR398a-5p and BR-induced miR156g. Although miR398a-5p is down-regulated by BRs, its predicted targets were not responsive to BRs. However, SPL3, a target of BR-inducible miR156g, is down-regulated by BRs. BR-responsive small RNAs and miRNAs identified in this study will provide an insight into the role of small RNAs in BR responses in plants. Especially, we suggest that miR156g/SPL3 module might play a role in BR-mediated growth and development in Arabidopsis.
Project description:We sequenced three small-RNA (sRNA) libraries constructed from leaves of sorghum subjected to three different treatments, well-watered (CK), mild drought (DR1) and severe drought (DR2). These findings will be useful for research on drought resistance and provide insights into the mechanisms of drought adaptation and resistance in sorghum.
Project description:RNA-seq analyses of drought-treated rice leaves were performed to screen long noncoding RNAs showing differential expression in a time-dependent manner.
Project description:The goal of this study is to idetify SL-responsive genes and drought-responsive genes downstream of OsWRKY31 and D53 in rice, by treating seedlings with or without GR244DO and drought.