Project description:Plant virus infection involves the production of viral small RNAs (vsRNAs) with the potential to associate with distinct Argonaute (AGO)-containing silencing complexes and mediate diverse silencing effects on RNA and chromatin. We used multiplexed, high-throughput pyrosequencing to profile populations of vsRNAs from plants infected with viruses from different genera. Sense and antisense vsRNAs of 20 to 24 nucleotides (nts) spread throughout the entire viral genomes in an overlapping configuration; virtually all genomic nucleotide positions were represented in the dataset. We present evidence to suggest that every genomic position could be a putative cleavage site for vsRNA formation, although viral genomes contain specific regions that serve as preferential sources of vsRNA production. Hotspots for vsRNAs of 21-, 22-, and 24-nt usually coincide in the same genomic regions, indicating similar target affinities among Dicer-like (DCL) enzymes. In the light of our results, the overall contribution of perfectly base paired double-stranded RNA and imperfectly base paired structures within single-stranded RNA to vsRNA formation is discussed. Our census of vsRNAs extends the current view of the distribution and composition of vsRNAs in virus-infected plants, and contributes to define a more comprehensive scenario of vsRNA biogenesis and their regulatory functions in plants Raw data files are available on our FTP site: ftp://ftp.ncbi.nlm.nih.gov/pub/geosup/Series/GSE16996
Project description:Plant virus infection involves the production of viral small RNAs (vsRNAs) with the potential to associate with distinct Argonaute (AGO)-containing silencing complexes and mediate diverse silencing effects on RNA and chromatin. We used multiplexed, high-throughput pyrosequencing to profile populations of vsRNAs from plants infected with viruses from different genera. Sense and antisense vsRNAs of 20 to 24 nucleotides (nts) spread throughout the entire viral genomes in an overlapping configuration; virtually all genomic nucleotide positions were represented in the dataset. We present evidence to suggest that every genomic position could be a putative cleavage site for vsRNA formation, although viral genomes contain specific regions that serve as preferential sources of vsRNA production. Hotspots for vsRNAs of 21-, 22-, and 24-nt usually coincide in the same genomic regions, indicating similar target affinities among Dicer-like (DCL) enzymes. In the light of our results, the overall contribution of perfectly base paired double-stranded RNA and imperfectly base paired structures within single-stranded RNA to vsRNA formation is discussed. Our census of vsRNAs extends the current view of the distribution and composition of vsRNAs in virus-infected plants, and contributes to define a more comprehensive scenario of vsRNA biogenesis and their regulatory functions in plants Raw data files are available on our FTP site: ftp://ftp.ncbi.nlm.nih.gov/pub/geosup/Series/GSE16996 10 samples examined: Arabidopsis plants infected with TRV, TuMV or CMV; Nicothiana benthamiana plants infected with CymRSV, PVX or PMMoV; Cucumis melo plants infected with MNSV, quimeric MNSV or WMV and Solanum lycopersicum plants infected with TYLCV.
Project description:High-throughput sequencing of Arabidopsis thaliana endogenous small RNAs by 454 pyrosequencing. Keywords: high-throughput sequencing
Project description:Comparison of the endogenous small RNA content of tomato leaves and fruits. Size fractionated small RNA from total RNA extracts was ligated to adapters, purified again and reverse transcribed. After PCR amplification the sample was subjected to 454 high throughput pyrosequencing. Please see www.454.com for details of the sequencing technology. Note: Raw data files were not available from 454 at the time this experiment was carried out.
Project description:Comparison of the endogenous small RNA content of Arabidopsis flower bud tissue: wild type vs. mutants in polIV pathways Keywords: High throughput 454 small RNA sequencing. Size fractionated small RNA from total RNA extracts was ligated to adapters, purified again and reverse transcribed. After PCR amplification the sample was subjected to 454 high throughput pyrosequencing. Please see www.454.com for details of the sequencing technology.
Project description:High-throughput sequencing of small RNAs from rice was used to identify distinct miRNAs that are responsive to elicitors from the fungal pathogen Magnaporthe oryzae. [Expression profiling by array] We used microarrays to determine the expression behaviour of target genes for elicitor-regulated miRNAs. [High throughput sequencing] High-throughput sequencing of rice small RNAs was performed in two different tissues, leaves and roots, and two different time point of elicitor treatment, 30' and 2h Amplicons were prepared by 5´and 3´adaptor ligation in which the 5'-adaptor contained a 'barcode' consisting of a 4-nucleotide identifier sequence for each sample. The libraries containing unique barcodes were combined and subjected to pyrosequencing (454 Life SciencesTM, Roche)
Project description:Vitis vinifera endogenous small RNAs Size fractionated small RNA from total RNA extracts of Vitis vinifera leaves, inflorescences, tendrils and small berries were ligated to adapters, purified again and reverse transcribed. After PCR amplification the sample was subjected to Solexa/Illumina high throughput pyrosequencing. Please see www.illumina.com for details of the sequencing technology.
Project description:Small RNAs of 20 to 25 nucleotides in length maintain genome integrity and control gene expression in a multitude of developmental and physiological processes. Despite RNA silencing has been primarily studied in model plants, the advent of high-throughput sequencing technologies has enabled profiling of the small RNA component of more than 40 plant species. Here, use deep sequencing and molecular methods to report the first inventory of small RNAs in olive (Olea europaea). Small RNAs of 24 nts dominate the small RNA transcriptome and atypically accumulate to levels never seen in other plant species, suggesting an active role of heterochromatin silencing in the maintenance and integrity of its large genome. By contrast, small RNAs of 20 to 22 nts were poorly represented in the population at levels lower than those found in most plant species tested. A total of 14 known miRNA families were identified in two libraries prepared from growing and dormant lateral buds. We found that some known miRNAs showed tissue- and/or developmental-specific expression. Also, seven novel, olive-specific miRNA candidates were found in our sequenced set of which 1 were supported by their star strands. Potential precursors for these miRNA candidates with intramolecular folding capacities were found in the olive EST database. Target mRNAs of conserved miRNAs and new olive-specific miRNA were computationally predicted among the olive EST collection and experimentally validated through endonucleolytic cleavage assays.
Project description:Medicago truncatula endogenous small RNAs The dataset contains Medicago truncatula Gaertn. cv. Jemalong endogenous small RNA sequences in the range 18-28 nucleotides. High-throughput Solexa/Illumina sequencing was carried out at the Sainsbury Laboratory, Norwich, UK. Please see www.illumina.com for details of the technology. Small RNA sequences were mapped to Medicago truncatula genome release 2.0 (http://www.medicago.org/genome/), the number of matches to the unfinished genome, if any, is recorded in the Series supplementary file GSE13761_sequence_annotations.txt.gz. Size fractionated small RNA from total RNA extracts was ligated to adapters, purified again and reverse transcribed. After PCR amplification the sample was subjected to Solexa/Illumina high throughput pyrosequencing. Please see www.illumina.com for details of the sequencing technology.
Project description:Small RNAs of 20 to 25 nucleotides in length maintain genome integrity and control gene expression in a multitude of developmental and physiological processes. Despite RNA silencing has been primarily studied in model plants, the advent of high-throughput sequencing technologies has enabled profiling of the small RNA component of more than 40 plant species. Here, use deep sequencing and molecular methods to report the first inventory of small RNAs in olive (Olea europaea). Small RNAs of 24 nts dominate the small RNA transcriptome and atypically accumulate to levels never seen in other plant species, suggesting an active role of heterochromatin silencing in the maintenance and integrity of its large genome. By contrast, small RNAs of 20 to 22 nts were poorly represented in the population at levels lower than those found in most plant species tested. A total of 14 known miRNA families were identified in two libraries prepared from growing and dormant lateral buds. We found that some known miRNAs showed tissue- and/or developmental-specific expression. Also, seven novel, olive-specific miRNA candidates were found in our sequenced set of which 1 were supported by their star strands. Potential precursors for these miRNA candidates with intramolecular folding capacities were found in the olive EST database. Target mRNAs of conserved miRNAs and new olive-specific miRNA were computationally predicted among the olive EST collection and experimentally validated through endonucleolytic cleavage assays. Two samples analyzed: growing (juvenile) and dormant (adult) lateral buds from the progeny of a genetic cross between the Picual and Arbequina olive varieties