Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Genome-wide double-stranded RNA sequencing reveals the functional significance of base-paired RNAs in Arabidopsis

ABSTRACT: The functional structure of all biologically active molecules is dependent on intra- and inter-molecular interactions. This is especially evident for RNA molecules whose functionality, maturation, and regulation requires formation of correct secondary structure through encoded base-pairing interactions. Unfortunately, intra- and inter-molecular base-pairing information is lacking for most RNAs. Here, we use high-throughput sequencing to interrogate all base-paired RNA in Arabidopsis thaliana, and identify ~200 new small (sm)RNA-producing substrates of RNA-DEPENDENT RNA POLYMERASE 6. Our comprehensive analysis of paired RNAs reveals conserved functionality within introns and both 5’ and 3’ untranslated regions (UTRs) of mRNAs, as well as a novel population of functional RNAs, many of which are the precursors of smRNAs. Finally, we identify intra-molecular base-pairing interactions to produce a genome-wide collection of RNA secondary structure models. These findings highlight the importance of base-paired RNAs in eukaryotes, and present an approach that should be widely applicable for the analysis of this key structural feature of RNA. Double-stranded (dsRNA) specific RNA sequencing (dsRNA-seq) in the unopened flowerbuds of wild-type col-0 plants and rdr6 mutant plants, including 2 samples of col-0 dsRNA (1X- or 2X- Ribominus-treated samples) and 1 sample of rdr6 dsRNA. Corresponding two smRNA libraries (smRNA-seq) of both wild-type col-0 plants and rdr6 mutant plants of the same tissue are also presented.

ORGANISM(S): Arabidopsis thaliana

SUBMITTER: Qi Zheng

PROVIDER: E-GEOD-23439 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

ACCESS DATA

Publications

Genome-wide double-stranded RNA sequencing reveals the functional significance of base-paired RNAs in Arabidopsis.

Zheng Qi Q Ryvkin Paul P Li Fan F Dragomir Isabelle I Valladares Otto O Yang Jamie J Cao Kajia K Wang Li-San LS Gregory Brian D BD

PLoS genetics 20100930 9

The functional structure of all biologically active molecules is dependent on intra- and inter-molecular interactions. This is especially evident for RNA molecules whose functionality, maturation, and regulation require formation of correct secondary structure through encoded base-pairing interactions. Unfortunately, intra- and inter-molecular base-pairing information is lacking for most RNAs. Here, we marry classical nuclease-based structure mapping techniques with high-throughput sequencing te ...[more]

PMID: 20941385

Similar Datasets

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).

Project description:MicroRNAs (miRNAs) are a class of small RNAs which typically function by guiding cleavage of target messenger RNAs. They have been shown to play major roles in a variety of plant processes including development, and responses to pathogens and environmental stresses. To identify new miRNAs and regulation in Arabidopsis thaliana, 27 small RNA libraries were constructed and sequenced from various tissues, stresses and small RNA biogenesis mutants, resulting in 95 million genome-matched sequences. The use of rdr2 to enrich the miRNA population greatly enhanced this analysis and led to the discovery of 44 new miRNAs arising from both known and new precursors. Parallel Analysis of RNA Ends (PARE) data provide evidence that the majority guide target cleavage. The inclusion of novel stress/tissue conditions, such as submergence-stressed flowers, enabled identification of new stress regulation of both miRNAs and their targets, all of which were validated in wild type plants. By combining small RNA expression analysis with ARGONAUTE (AGO) immunoprecipitation data and global target cleavage data from PARE, a much more complete picture of Arabidopsis miRNAs was obtained. This combinatorial approach led to the discovery of AGO loading and target cleavage biases, which gave important insights into tissue-specific expression patterns, pathogen responses and the role of sequence variation among closely related miRNA family members. Examination of various tissues, stresses and small RNA biogenesis mutants in Arabidopsis by high-throughput sequencing for small RNA profiling. We have used AGO-IP and PARE data from the published data, which were downloaded from NCBI GEO with the following accession number. AGO-IP from GSM253622, GSM707682, GSM642335, GSM642336, GSM512703, GSM512702, GSM707683, GSM707684, GSM707685, GSM149080, GSM253623, GSM304283, GSM642337, GSM642338, GSM253624, GSM415788, GSM707686, GSM707687, GSM707688, GSM707689, GSM415787, GSM149081, GSM253625, GSM415789, GSM415790, GSM304285, GSM415791, GSM415792 PARE sequencing data from xrn4 flowers were obtained from Gene Expression Omnibus with accession number GSM280227.

Project description:Post-transcriptional gene silence (PTGS) is employed in plants to shut down transgenes, invading viral genes and a certain group of endogenous genes. Meanwhile, it is not clear how the risk of expansive PTGS from endogenous genes featured by transitive siRNA production is minimized. Here we demonstrate two essential components of the SKI complex in cytoplasmic 3’-5’ mRNA decay pathway, SKI2 and SKI3, function as negative regulators of transgene PTGS in Arabidopsis. The ski2 mutants manifested severe synthetic phenotypes with a 5’-3’ exoribonuclease mutant, ein5, which were substantially suppressed by the PTGS mutants, rdr6 and ago1. RDR6 is essential for the altered gene expression in ein5 ski2 on a transcriptome-wide scale. mRNA-seq approach was used to investigate the physiological relevance veiled by the myriad developmental phenotypes in Col-0 (C), ein5-1 (e), ski2-3 (s), ein5-1 ski2-3 (es), rdr6-11 (r) and rdr6-11 ein5-1 ski2-3 (res). Compared with Col-0, 4394 genes exhibited differential expression in ein5-1 ski2-3, much more than those in the ein5-1 (1138 genes) or ski2-3 (1040 genes) single mutant (2-fold cutoff, p < 0.01, FDR < 0.05), suggesting a largely disturbed transcriptome in the absence of both EIN5 and SKI2. While a small overlap was found between the differentially expressed genes in e/C and s/C comparisons, the gene lists from es/C, es/e and es/s comparisons (2-fold cutoff, p < 0.01, FDR < 0.05) largely overlapped with each other, indicating a collaborative function of EIN5 and SKI2 on a transcriptome-wide scale. The 1670 genes overlapped in the es/C, es/e and es/s comparisons included 1306 upregulated genes and 360 downregulated genes with only 4 genes as exception. 994 of the 1306 upregulated genes (76.1%) and 273 of the 360 downregulated genes (75.8%) were differentially expressed in the es/res comparison like that in es/C, es/e and es/s, indicating a substantial supression of the redundant function of EIN5 and SKI2 by RDR6. Taken together, our study brings to light a dual-safeguard system in preventing the expansive siRNA production by the 5’-3’ and 3’-5’ cytoplasmic mRNA decay pathways. Examination of transcriptomes in 6 genotypes.

Project description:Backgropund:In a major paradigm shift in the last decade, the knowledge about a whole class of non-coding RNAs known as miRNAs has emerged, which have proved these to be important regulators of a wide range of cellular processes by the way of modulation of gene expression. It is reported that some of these miRNAs are modified by addition or deletion of nucleotides at their ends, after biogenesis. However, the biogenesis and functions of these modifications are not well studied in eukaryotes, especially in plants. In this study, we examined the miRNA modifications in different tissues of the various plants, namely rice, tomato and Arabidopsis and identified some common features of such modifications. Results:We have analyzed different aspects of miRNA modifications in plants. To achieve this end, we developed a PERL script to find the modifications in the sequences using small RNA deep sequencing data. The modification occurs in both mature and passenger (star) strands, as well as at both the 5' and 3' ends of miRNAs. Interestingly, we found a position-specific nucleotide biased modification, as evident by increased number of modification at the 5' end with the presence of Cytosine (nucleotide 'C') at the 3âend of the miRNA sequence. The level of modifications is not strictly dependent on the abundance of miRNA. Our study showed that the modification events are independent of plant species, tissue and physiological conditions. Our analysis also indicates that the RNAi enzyme, namely, the RNA dependent RNA polymerase 6 (RDR6) may not have any role in Arabidopsis miRNA modifications. Some of these modified miRNAs are bound to AGO1, suggesting their possible roles in biological processes. Conclusions:This is a first report that reveals that 5' nucleotide additions are preferred for mature miRNA sequences with 3â terminal âCâ nucleotide. Our analysis also indicates that the miRNAs modifications involving addition of nucleotides to the 5â or 3â end are independent of RDR6 activity and are not restricted by plant species, physiological conditions and tissue types. The results also indicate that such modifications might be important for biological processes. small RNA profiles of wild type and RDR6 (-) of Arabidopsis plants were generated using deep sequencing data.

Dataset Information

Genome-wide double-stranded RNA sequencing reveals the functional significance of base-paired RNAs in Arabidopsis

Publications

Genome-wide double-stranded RNA sequencing reveals the functional significance of base-paired RNAs in Arabidopsis.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets