Arabidopsis thaliana
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA301359 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Parallel RNA silencing pathways regulate gene expression in plants, either by transcriptional gene silencing via RNA-dependent DNA methylation (RdDM), or by post-transcriptional silencing targeting mRNAs. Both pathways rely on distinct Dicer-like proteins to cleave double-stranded RNA into small-interfering RNAs. Experiments to determine the subcellular localization of Dicer-like proteins in Arabidopsis revealed that DCL4 is predominantly expressed as a transcriptional start site isoform that encodes a cytoplasmic protein. A second, longer DCL4 transcript isoform encodes a nuclear-localization signal and its expression is repressed by DNA methylation. Consequently this isoform is induced when promoter methylation decreases due to infection with a bacterial pathogen or during silique development. Nuclear DCL4 produces unique populations of small RNAs, called DCL4NLS isoform-dependent siRNAs (disiRNAs), which function via a post-transcriptional silencing effector, but whose precursors are generated by the RdDM pathway. Arabidopsis cells can thus respond to genome methylation changes by modulating DCL4 localization, which in turn recruits PTGS factors to reinforce RNA silencing.
2016-11-14 | GSE74731 | GEO
Project description:Small RNAs in the Physcomitrella dcl4 mutant
| PRJNA118191 | ENA
Project description:Here we profiled small RNAs from whole cell, cytoplasmic and nuclear extracts from three-week-old Arabidopsis seedlings. We unexpectedly found that nuclear functional hc-siRNAs are predominantly present in the cytoplasm. Samples from Arabidopsis thaliana whole cell, cytoplasmic and nuclear extracts with 3 replicates for each. 9 samples in all.
2012-07-12 | E-GEOD-36500 | biostudies-arrayexpress
Project description:To study the function of Physcomitrella DCL4, a knockout plant line was created. Small RNAs from ~10-day old protonemata were obtained and sequenced using a SOLiD 2 instrument. A single library each was made from dcl4 mutant protonemata and wild-type protonemata. The dcl4 library was sequenced in four separate technical replicates. The wild-type sample was subject to a single sequencing run.
2012-04-01 | E-GEOD-18466 | biostudies-arrayexpress
Project description:High-throughput pyrosequencing of endogenous small RNAs from Arabidopsis thaliana wild-type and ddm1 mutant.
| PRJNA110069 | ENA
Project description:Dicer enzymes function at the core of RNA silencing to defend against exogenous RNA, or as an endogenous mechanism of gene regulation. Plant DICER-LIKE4 (DCL4) performs dual functions, acting in antiviral defense, as well as in development via the biogenesis of tasiR-ARFs. These small RNAs play an essential role in the grasses and act to spatially define the expression domain of AUXIN RESPONSE FACTOR3 (ARF3) transcription factors. However, contrary to tasiR-ARFs’ essential function in development, DCL4 proteins exhibit strong evidence of recurrent adaptation typical of host factors involved in antiviral immunity. Here, we address how DCL4 balances its role in development with pressures to diversify in response to viral attack. We show that, in contrast to other tasiR-ARF biogenesis mutants, dcl4 null alleles condition an uncharacteristically mild phenotype, correlated with normal expression of select arf3 targets. Loss of DCL4 activity yields a class of 22-nt tasiR-ARF variants associated with the processing of arf3 transcripts into 22-nt secondary siRNAs by DCL1. Our findings uncover the presence of a novel DCL1-dependent siRNA pathway that bypasses the otherwise adverse developmental effects of DCL4 mutations. This novel pathway is predicted to have important implications for DCL4’s role in antiviral defense by reducing the selective constraints on DCL4 and allowing it to diversify in response to viral suppressors. Examination of small RNAs isolated from dcl4, dcl1 and double mutants in imbibed kernels of maize
2015-09-01 | E-GEOD-66986 | biostudies-arrayexpress
Project description:We detect the small RNAs subcellular distribution in breast cancer cell lines MCF-7 and MDA-MB-231, and normal cell line MCF-10A. Each cell line, we detected the nuclear and cytoplasmic small RNAs expression intensity; and then we could get the nuclear-cytoplasmic-ratio.
2010-05-18 | E-GEOD-15937 | biostudies-arrayexpress
Project description:The osdcl4-1 mutant exhibits much severer developmental defects than dcl4 in Arabidopsis, suggesting that Os DCL4 may process broader substrates in rice. By deep sequencing of small RNAs from different tissues of wild types and osdcl4-1, we revealed that 21-nucleotide siRNAs were largely dependent on Os DCL4. Besides several tasiRNA loci reported in Arabidopsis and rice, over one thousand 21-nucleotide and several dozen 24-nucleotide phased siRNA (phasiRNA) clusters were identified in panicles but not in seedlings and grains. Further analyses identified two conserved 22-nucleotide motifs among the cleavage sites of the 21- and 24- phasiRNA loci, and the cleavage sites of over 90% of 21- and 24-nucleotide phasing clusters were confirmed by PARE/degradome analysis from 93-11 panicles. MiR2118 and miR2275, expressed specifically in panicles, were predicted to trigger cleavages at 21- and 24-nucleotide phasiRNA clusters, respectively. The triggers of phasiRNAs are more dependent on Os DCL4 than Os DCL1. Furthermore, the processing of 21-nucleotide phasiRNAs was largely Os DCL4-dependent, whereas the processing of 24-nucleotide phasiRNAs was slightly affected by Os DCL4, but not by Os DCL3a and Os DCL1. Our results revealed distinct roles of Os DCL4 in a novel 21- and 24-nucleotide phasiRNA biogenesis pathway in rice. Six small RNA libraries were constructed from seedlings and panicles of 93-11 (a wild-type Indica rice variety) and osdcl4-1, as well as those from Nipponbare panicles and seedlings (a wild-type Japonica rice variety).
2012-03-29 | E-GEOD-22763 | biostudies-arrayexpress
Project description:To determine the extent to which the major small RNA pathways functions across the Arabidopsis thaliana genome, small RNA populations from several tissues of wild-type (wt) and mutant plants were amplified by RT-PCR and sequenced using high-throughput 454 sequencing technology. Keywords: small RNAs, high-throughput sequencing Amplicons were prepared by 5' and 3' adaptor ligation and RT-PCR using small RNA fractions from inflorescence tissue (containing stage 1-12 flowers) of wt Col-0 plants, mutants with defects in each DCL gene (dcl1-7, dcl2-1, dcl3-1, dcl4-2), and mutants with defects in each RDR gene for which a function has been established (rdr1-1, rdr2-1, rdr6-15). Amplicons from whole seedlings (3 day post-germinations) were prepared from Col-0 and rdr6-15 plants. Small RNA preparations from leaf samples of Col-O that were either uninoculated or inoculated by Pseudomonas syringae pv tomato (DC3000hrcC) for 1 hr and 3 hr were also sequenced.
2007-02-01 | E-GEOD-6682 | biostudies-arrayexpress
Project description:In the model plant Arabidopsis thaliana, four Dicer-like proteins (DCL1-4) mediate the production of various classes of small RNAs (sRNAs). Among these four proteins, DCL4 is by far the most versatile RNaseIII-like enzyme and previously identified dcl4 missense alleles were shown to uncouple the production of the various classes of DCL4-dependent sRNAs. Yet, little is known about the molecular mechanism pertaining this uncoupled production. Here, by studying the subcellular localization, interactome and binding to the sRNA precursors of three distinct dcl4 missense alleles, we simultaneously highlight the absolute requirement of its helicase domain for efficient production of all DCL4-dependent sRNAs, and identify an important determinant of DCL4 versatility within its PAZ domain that is mandatory for efficient processing of intramolecular foldback dsRNA precursors but dispensable for the production of siRNAs from RDR-dependent dsRNA susbtrates. This study not only provides novel insights into DCL4 mode of action in plants but also delineates interesting tools to further study the complexity of plant RNA silencing pathways.
2018-04-24 | GSE106383 | GEO