Nicotiana tabacum
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA387281 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:MicroRNAs (miRNAs) are ~21nt long endogenous non-coding RNAs that are involved in post-transcriptional silencing of target mRNAs. miRNAs are processed from precursors having a stem-loop structure that are recognized and cleaved by Dicer-like 1 (DCL1) with the help of dsRNA binding protein Hyponastic leaves 1 (HYL1) and a zinc finger protein named Serrate (SE). Plant miRNA stem-loops are very diverse in length and structure than animal miRNAs. Hence, mechanism of miRNA biogenesis from their precursors is poorly understood. Our bioinformatic analysis predicted that plant miRNAs have unique sequence signature. An artificial precursor with different predicted sequence signatures was constructed. This construct was expressed transiently in tobacco leaves and small RNAs were sequenced. Our analysis revealed that indeed the predicted sequence signature is prefered by plant miRNA biogenesis machinery.
2017-07-15 | GSE99094 | GEO
Project description:Small RNAs (21-24 nt) are pivotal regulators of gene expression that guide both transcriptional and post-transcriptional silencing mechanisms in diverse eukaryotes, including most if not all plants. MicroRNAs (miRNAs) and short interfering RNAs (siRNAs) are the two major types, both of which have a demonstrated and important role in plant development, stress responses and pathogen resistance. In this work, we used a deep sequencing approach (Sequencing-By-Synthesis, or SBS) to develop sequence resources of small RNAs from Nicotiana tabacum tissues (including leaves, flowers and pods). The high depth of the resulting datasets enabled us to examine in detail critical small RNA features as size distribution, tissue-specific regulation and sequence conservation between different organs in this species. We also developed database resources and a dedicated website (http://smallrna.udel.edu/) with computational tools for allowing other users to identify new miRNAs or siRNAs involved in specific regulatory pathways, verify the degree of conservation of these sequences in other plant species and map small RNAs on genes or larger regions of the maize genome under study.
2011-05-10 | GSE28977 | GEO
Project description:Small RNAs (21-24 nt) are pivotal regulators of gene expression that guide both transcriptional and post-transcriptional silencing mechanisms in diverse eukaryotes, including most if not all plants. MicroRNAs (miRNAs) and short interfering RNAs (siRNAs) are the two major types, both of which have a demonstrated and important role in plant development, stress responses and pathogen resistance. In this work, we used a deep sequencing approach (Sequencing-By-Synthesis, or SBS) to develop sequence resources of small RNAs from Nicotiana tabacum tissues (including leaves, flowers and pods). The high depth of the resulting datasets enabled us to examine in detail critical small RNA features as size distribution, tissue-specific regulation and sequence conservation between different organs in this species. We also developed database resources and a dedicated website (http://smallrna.udel.edu/) with computational tools for allowing other users to identify new miRNAs or siRNAs involved in specific regulatory pathways, verify the degree of conservation of these sequences in other plant species and map small RNAs on genes or larger regions of the maize genome under study. Small RNA libraries were derived from leaves, flowers and pods of Nicotiana tabacum. Total RNA was isolated using the TriReagent (Molecular Research Center) for leaves and flowers, and the Plant RNA Purification Reagent (Invitrogen) for pods, and submitted to Illumina (Hayward, CA, http://www.illumina.com) for small RNA library construction using approaches described in (Lu et al., 2007) with minor modifications. The small RNA libraries were sequenced with the Sequencing-By-Synthesis (SBS) technology by Illumina. PERL scripts were designed to remove the adapter sequences and determine the abundance of each distinct small RNA. We thank Barbara Baker for providing the plant material as well as Kan Nobuta and Gayathri Mahalingam for assistance with the computational methods.
2011-05-09 | E-GEOD-28977 | biostudies-arrayexpress
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Project description:MicroRNAs (miRNAs) are processed from longer precursors with fold-back structures. While animal MIRNA precursors have homogenous structures, plant precursors comprise a collection of fold-backs with variable size and shape. Here, we design an approach (SPARE) to systematically analyze miRNA processing intermediates and characterize the biogenesis of most of the evolutionary conserved miRNAs present in Arabidopsis thaliana. We found that plant MIRNAs are processed by four mechanisms, depending on the sequential direction of the processing machinery and the number of cuts required to release the miRNA. Classification of the precursors according to their processing mechanism revealed specific structural determinants for each group. We found that the complexity of the miRNA processing pathways occurs in both ancient and evolutionary young sequences, and that members of the same family can be processed in different ways. We observed that different structural determinants compete for the processing machinery and that alternative miRNAs can be generated from a single precursor. The results provide a mechanistic explanation for the structural diversity of MIRNA precursors in plants and new insights towards the understanding of the biogenesis of small RNAs. Approach to systematically analyze miRNA processing intermediates and characterize the biogenesis of conserved and young miRNAs present in Arabidopsis thaliana. MiRNA processing intermediates profiles of Wild type and Fiery mutants Arabidopsis plants were analyzed, using Illumina GAIIx.
2013-06-12 | E-GEOD-46429 | biostudies-arrayexpress
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Project description:Many evolutionarily conserved miRNAs in plants regulate transcription factors with key functions in plant development. Hence, mutations in core components of the miRNA biogenesis machinery causes strong growth defects. An essential aspect of miRNA biogenesis is the precise excision of the small RNA from an arm of the fold-back precursor. Defects in the selection of the correct miRNA sequence will ultimately affect miRNA target specificity, plant development and other processes controlled by these small RNAs. Intriguingly, plant miRNA precursors are largely variable in size and shape and can be processed by different modes. Here, we optimized genomic approaches to detect processing intermediates during miRNA biogenesis. We identified and characterized an endogenous miRNA whose processing is triggered by a terminal branched loop. Plant miRNA processing can be initiated by internal bubbles, small terminal loops or branched loops followed by dsRNA segments of 15-17 bp. Interestingly, precision and efficiency vary with the processing modes suggesting intrinsic differences between miRNA biogenesis pathways. Despite the various potential structural determinants present in a single a miRNA precursor, we found that DCL1 is mostly guided by a predominant structural region in each precursor in wild-type plants. However, genomic studies of miRNA processing intermediates in fiery1, hyl1 and se mutants revealed the existence of cleavage signatures consistent with the recognition of alternative or cryptic processing determinants in miRNA precursors. The results provide a general view of the mechanisms underlying the specificity of miRNA biogenesis in plants.
2018-09-11 | GSE116330 | GEO
Project description:Many evolutionarily conserved miRNAs in plants regulate transcription factors with key functions in plant development. Hence, mutations in core components of the miRNA biogenesis machinery causes strong growth defects. An essential aspect of miRNA biogenesis is the precise excision of the small RNA from an arm of the fold-back precursor. Defects in the selection of the correct miRNA sequence will ultimately affect miRNA target specificity, plant development and other processes controlled by these small RNAs. Intriguingly, plant miRNA precursors are largely variable in size and shape and can be processed by different modes. Here, we optimized genomic approaches to detect processing intermediates during miRNA biogenesis. We identified and characterized an endogenous miRNA whose processing is triggered by a terminal branched loop. Plant miRNA processing can be initiated by internal bubbles, small terminal loops or branched loops followed by dsRNA segments of 15-17 bp. Interestingly, precision and efficiency vary with the processing modes suggesting intrinsic differences between miRNA biogenesis pathways. Despite the various potential structural determinants present in a single a miRNA precursor, we found that DCL1 is mostly guided by a predominant structural region in each precursor in wild-type plants. However, genomic studies of miRNA processing intermediates in fiery1, hyl1 and se mutants revealed the existence of cleavage signatures consistent with the recognition of alternative or cryptic processing determinants in miRNA precursors. The results provide a general view of the mechanisms underlying the specificity of miRNA biogenesis in plants.
2018-09-11 | GSE112632 | GEO
Project description:RNA sequencing of plant microRNAs precipitated by the tombusviral suppressor of RNA silencing p19.
| PRJNA386909 | ENA
Project description:MicroRNAs (miRNAs) are processed from longer precursors with fold-back structures. While animal MIRNA precursors have homogenous structures, plant precursors comprise a collection of fold-backs with variable size and shape. Here, we design an approach (SPARE) to systematically analyze miRNA processing intermediates and characterize the biogenesis of most of the evolutionary conserved miRNAs present in Arabidopsis thaliana. We found that plant MIRNAs are processed by four mechanisms, depending on the sequential direction of the processing machinery and the number of cuts required to release the miRNA. Classification of the precursors according to their processing mechanism revealed specific structural determinants for each group. We found that the complexity of the miRNA processing pathways occurs in both ancient and evolutionary young sequences, and that members of the same family can be processed in different ways. We observed that different structural determinants compete for the processing machinery and that alternative miRNAs can be generated from a single precursor. The results provide a mechanistic explanation for the structural diversity of MIRNA precursors in plants and new insights towards the understanding of the biogenesis of small RNAs.
2013-06-12 | GSE46429 | GEO