A global profiling of uncapped mRNAs under cold stress reveals specific decay patterns and endonucleolytic cleavages in Brachypodium
Ontology highlight
ABSTRACT:
ORGANISM(S): Brachypodium distachyon
SUBMITTER: zhang jingyu
PROVIDER: E-GEOD-48234 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Similar Datasets
Project description:RNA-Seq was performed to study the change of gene expression before and after cold treatment in Brachypodium. Different change patterns were identified. We have provided a complete view of transcriptome under cold stress condition, which will deepen our understanding of gene expression regulation in cold stress response as well as cold stress response mechanism for monocot plants. The mRNA profiles of 12-day-old Brachypodium seedlings with and without cold treatment (4 M-BM-0C for 24 h) were generated by deep sequencing using Illumina HiSeqM-bM-^DM-" 2000.
2013-07-15 | E-GEOD-48040 | biostudies-arrayexpress
Project description:ABSTRACT: Exposure to abiotic stresses triggers global changes in the expression of thousands of eukaryotic genes at the transcriptional 70 and post-transcriptional levels. Small RNA (smRNA) pathways and splicing both function as crucial mechanisms regulating stress-responsive gene expression. However, examples of smRNAs regulating gene expression remain largely limited to effects on mRNA stability, translation, and epigenetic regulation. Also, our understanding of the networks controlling plant gene expression in response to environmental changes, and examples of these regulatory pathways intersecting, remains limited. Here, to investigate the role of smRNAs in stress responses we examined smRNA transcriptomes of Brachypodium distachyon plants subjected to various abiotic stresses. We found that exposure to different abiotic stresses specifically induced a group 75 of novel, endogenous small interfering RNAs (stress-induced, UTR-derived siRNAs, or sutr-siRNAs) that originate from the 3M-bM-^@M-2 UTRs of a subset of coding genes. Our bioinformatics analyses predicted that sutr-siRNAs have potential regulatory functions and that over 90% of sutr-siRNAs target intronic regions of many mRNAs in trans. Importantly, a subgroup of these sutr- siRNAs target the important intron regulatory regions, such as branch point sequences, that could affect splicing. Our study indicates that in Brachypodium, sutr-siRNAs may affect splicing by masking or changing accessibility of specific cis-elements 80 through base-pairing interactions to mediate gene expression in response to stresses. We hypothesize that this mode of regulation of gene expression may also serve as a general mechanism for regulation of gene expression in plants and potentially in other eukaryotes. Analysis of smRNA populations in Brachypodium plants challenged by abiotic stresses: To profile the populations of smRNAs in the model monocot Brachypodium distachyon and examine their regulation in response to abiotic stresses, we conducted high-throughput sequencing of small RNAs from plants exposed to four different abiotic stress conditions, cold, heat (air), heat (water immersion), and salt, in the wild type Brachypodium cultivar Bd21. For our experiments we used information from the literature to select two time-points for stress durations, short and long, which differed for each stress: cold (6 and 24 hours), heat-air (1 and 3 hours), heat-water (1 and 3 hours), and salt (48 hours). We generated small RNA libraries for Illumina sequencing (GAII) from the leaves of Brachypodium plants subjected to stresses and selected smRNAs between 15 and 40 nt in length, which we mapped to the Brachypodium genome.
2015-01-20 | E-GEOD-55217 | biostudies-arrayexpress
Project description:PARE (parallel analysis of RNA ends) was performed to study the change of uncapped mRNAs before and after cold treatment in Brachypodium. Different change patterns were identified. We have provided a complete view of uncapped transcriptome under cold stress condition, which will deepen our understanding of gene expression regulation in cold stress response as well as cold stress response mechanism for monocot plants.
2013-07-15 | GSE48234 | GEO
Project description:The wild grass Brachypodium distachyon has emerged as a model system for temperate grasses and biofuel plants. However, the global analysis of miRNAs, molecules known to be key for eukaryotic gene regulation, has been limited in B. distachyon to studies examining a few samples or that rely on computational predictions. Similarly an in-depth global analysis of miRNA-mediated target cleavage using Parallel Analysis of RNA Ends (PARE) data is lacking in B. distachyon. B. distachyon small RNAs were cloned and deeply sequenced from 17 libraries that represent different tissues and stresses. Using a computational pipeline, we identified 116 miRNAs including not only conserved miRNAs that have not been reported in B. distachyon, but also non-conserved miRNAs that were not found in other plants. To investigate miRNA-mediated cleavage function, four PARE libraries were constructed from key tissues and sequenced to a total depth of approximately 70 million sequences. The roughly 5 million distinct genome-matched sequences that resulted represent an extensive dataset to analyze small RNA-guided cleavage events. Analysis of the PARE and miRNA data provided experimental evidence for miRNA-mediated cleavage of 264 sites in predicted miRNA targets. In addition, PARE analysis revealed that differentially expressed miRNAs in the same family guide specific target RNA cleavage in a correspondingly tissue-preferential manner. B. distachyon miRNAs and target RNAs were experimentally identified and analyzed. Knowledge gained from this study should provide insights into the roles of miRNAs and the regulation of their targets in B. distachyon and related plants. Examination of various tissues and stresses in Brachypodium by high throughput sequencing for small RNA profiling and PARE (Parallel Analysis of RNA Ends)
2013-12-06 | E-GEOD-52441 | biostudies-arrayexpress
Project description:Purpose: The goal of this study is to compare the transcriptomes expressed during submergence stress of two Brachypodium distachyon ecotypes with contrasting survival under this stress. Bd21 is a submergence sensitive ecotype with EC50 of 2.5 days and Bd2-3 is a tolerant ecotype with EC50 of 4 days. Methods (Stress): Brachypodium Bd21 and Bd2-3 plants (14-day-old, 6 leaves stage) were submerged in a water column of 30 cm inside opaque-wall plastic tanks. Light still reached the plants at 40 uE m-2 s-??1. Ecotypes were submerged side-by-side in a randomized manner; only plants submerged in the same tank were compared. Controls were grown in plastic tanks without a water column. Submergence stress started at ZT14 (2h before night, long-day regime 16h light, 8h dark). Above ground tissue was collected after 48 h submergence stress in liquid nitrogen and stored at -80C in an ultra freezer until further processing. Tissue was ground to powder with mortar, pestle and liquid nitrogen avoiding thawing. Control and submerged total RNA was extracted with TRIzol reagent (Invitrogen, 15596018), purified with Direct-zol RNA mini prep columns (Zymo Research, R2050) and digested in-column with DNAse I (ThermoScientific, EN0521). RNA integrity and concentration was verified in denaturing 1.0% agarose gels, Nanodrop 2000 (ThermoScientific) and in a Bioanalyzer 2100 (Agilent) with the integrated software 2100 Expert, samples had a RNA Integrity Number (RIN) between 6.4-7.2 characteristic of aerial plant tissue (Babu and Gassman, 2011). Total RNA extracted from control and submerged tissue from three independent experiments consisting each of four individuals were used to construct cDNA indexed libraries and sequenced in a HiSeq2500 (Illumina) at 1x50 format, making a total of 12 sequenced libraries (tolerant and intolerant ecotype, control and submerged, all experimental triplicates) in a 2-lane format. RNA integrity, library construction and sequencing was performed as a service at the Unidad Universitaria de Secuenciacion Masiva, Instituto de Biotecnologia, Universidad Nacional Autonoma de Mexico (IBT-UNAM). Differential Gene Expression (DGE) analysis was performed with edgeR using a generalized linear model and false discovery rate <0.05 (FDR). To group differentially expressed transcripts a logFC value of 1.5 (up-regulated) or -1.5 (down-regulated) and a FDR <0.05x10-5 were selected. GO analysis of differential transcripts was performed at phytozome.org Results: We identified commonly up-regulated genes (317) and exclusively up-regulated in Bd2-3 (466) or Bd21 (706). Regarding down-regulation, 330 transcripts were common, an exclusively 851 and 1026 for Bd2-3 and Bd21, respectively. GO analysis indicated that oxidative stress, pathogen responses and nitric oxide homeostasis were the most differential characteristics of tolerant ecotype Bd2-3. Conclusions: The use of triplicate RNAseq data of transcriptomes expressed in ecotypes with contrasting tolerance to submergence under long-day light regime, allowed us to identify common responsive routes such as SUSY, glycolysis, anaerobic routes (alanine, ethanol, lactate, GABA) and glyoxylate cycle. It also enabled us to discover integrated oxidative stress and NO homeostasis pathways that are differentially expressed in the tolerant ecotype. We expect that this information can be translated to agricultural relevant plants to increase our knowledge and biotechnological possibilities on plant submergence stress. Sequenced libraries (triplicates, HiSeq2500 Illumina, 1x50 format) of aerial tissue (control and 48h submergence stress) of Brachypodium distachyon Bd21 (sensitive) and Bd2-3 (tolerant).
2016-01-04 | E-GEOD-74222 | biostudies-arrayexpress
Project description:The small RNAs and their targets were characterized in Amborella genome by deep sequencing the small RNA populations of leaf tissue and opened-female flower tissue. The small RNA targets were also validated from degradome populations of leaf tissue and opened-female flower tissue. We generated integrative maps of small RNA profiles (sRNA-seq) and degradome (PARE-seq) profiles to characterize the miRNAs and their targets from Amborella.
2013-07-01 | E-GEOD-41811 | biostudies-arrayexpress
Project description:The small RNA transcriptomes of bread wheat (Triticum aestivum L.) and its emerging model (Brachypodium distachyon (L.) Beauv) were obtained by using deep sequencing technology. Small RNA compositions were analyzed in these two species. In addition to 70 conserved microRNAs (miRNA) from 25 families, 23 novel wheat miRNAs were identified. For Brachypodium, 12 putative miRNAs were predicted from a limited number of ESTs, of which one was a potential novel miRNA. Also, 94 conserved miRNAs from 28 families were identified in this species. Expression validation was performed for several novel wheat miRNAs. RNA ligase-mediated 5' RACE experiments demonstrated their capability to cleave predicted target genes including three disease resistant gene analogs. Differential expression of miRNAs was observed between Brachypodium vegetative and reproductive tissues, suggesting their different roles at the two growth stages. Our work significantly increases the novel miRNA numbers in wheat and provides the first set of small RNAs in Brachypodium distachyon. Keywords: Small RNA One wheat small RNA library (Tae) and two Brachypodium small RNA libraries (BdR and BdV) were sequenced.
2009-06-07 | E-GEOD-16177 | biostudies-arrayexpress
Project description:RNA-Seq was performed to study the change of gene expression before and after cold treatment in Brachypodium. Different change patterns were identified. We have provided a complete view of transcriptome under cold stress condition, which will deepen our understanding of gene expression regulation in cold stress response as well as cold stress response mechanism for monocot plants.
2013-07-15 | GSE48040 | GEO
Project description:miRNA levels depend on both biogenesis and turnover. The methyltransferase HEN1 stabilizes plant miRNAs, animal piRNAs, and siRNAs in both kingdoms via 3' terminal methylation. Loss of HEN1 in plants results in non-templated oligo-uridylation and accelerated degradation of miRNAs. In hen1 mutants from Arabidopsis and rice, we found that the patterns of miRNA truncation and uridylation differ substantially among miRNA families, but such patterns for the same miRNA are conserved between species. miR166 and miR163 are truncated predominantly to ~17 and ~16 nt, and subsequently recover via uridylation to approximately their original sizes, 21 and 24 nt, suggesting that in these cases miRNA truncation triggers uridylation. miR171 is untruncated but uridylated to 22 nt in hen1 mutants, gaining the ability to trigger production of phased, secondary siRNAs. Truncated and tailed variants were bound by ARGONAUTE1 (AGO1) in hen1, implying that these events occur while miRNAs are still bound by AGO1. Unexpectedly, a portion of miR158 in wildtype remains unmethylated and thus subject to uridylation and destabilization, suggesting that plants naturally utilize miRNA methylation to modulate miRNA accumulation. Our results suggest that the AGO1-containing RISC complex may undergo programming to reflect each bound miRNA, determining a defined, distinct decay destiny. In this analysis, we sequenced sRNAs from two hen1 mutant alleles in Arabidopsis and three hen1 alleles in rice. In Arabidopsis, the strong hen1-1 allele in the Landsberg erecta (Ler) ecotype is the first hen1 mutant and emerged from an enhancer screen in the hua1-1/hua2-1 background, and hen1-8 in the Columbia (Col) background is a weak allele. In rice, WAVY LEAF1 (WAF1) is the ortholog of Arabidopsis HEN1, and two mutant alleles waf1-1 and waf1-2 each bear a single-base substitution leading to a premature stop codon in the second exon and a non-functional splicing site of the fourth intron, respectively. We identified a third mutant allele of the rice HEN1 gene (Oshen1-3 from the Korean (POSTEC) rice T-DNA mutant population).
2013-07-22 | E-GEOD-35562 | biostudies-arrayexpress
Project description:Transcriptomic analyses are particularly powerful in research when they are based on detailed underlying knowledge of developmental processes, morphological/anatomical features and biochemical/metabolic processes. Our work is based on our detailed knowledge of grain development and provides an invaluable resource for both Brachypodium grain development specifically and for comparative analyses to other species, including cereal crops. Grain development includes several transition points in addition to being preceded and succeeded by the fundamental developmental switches of fertilization and germination. Such complex process requires a larger sets of genes expressed in a highly-controlled manner. We have selected eight stages of developmental in Brachypodium distachyon encompassing these transitions and conducted comprehensive transcriptomic analyses to generate a valuable resource of the developmental transitions and the distinctive biological processes that are activated and/or repressed during grain development and germination. Comparison of the data generated in this project to other grasses, including the important crop species, and beyond will also shed light on the conservation and/or diversification in gene expression and function in an evolutionary context. Brachypodium distachyon grains (Bd-21 accession) were germinated on moist filter paper after stratification at 4°C for 48h. Five-day old seedlings were transferred to 9cm square pots with a 2:2:1 multipurpose compost: vermiculite: sand mix and grown under controlled environment conditions with a 18h photoperiod at 20°-22°C and light intensity of 180-200 umol/m/s. Tissue samples were collected from eight distinct developmental stages; pre-anthesis ovaries, young grains (1-3 DAA), middle length grains (3-8 DAA), full length grains (8-15 DAA), mature grains (15-20 DAA), mature grains without embryo, germinating grains and seedlings at 3-4 days after germination (Fig.1). Tissues were frozen in liquid nitrogen immediately after collection and were kept at -80°C until further analyses. Total RNA was isolated from frozen tissue samples using the Spectrum Plant Total RNA Kit (Sigma-Aldrich) following the manufacturer’s instructions. Three biological replicates were used for each stage of development. The RNA samples were treated with DNase I (New England Biolabs) in order to eliminate DNA contamination and their concentration was determined using a NanoDrop spectrophotometer (Thermo Fisher Scientific).
2019-01-31 | E-MTAB-7607 | biostudies-arrayexpress