Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

The high-throughput cleavage assays on 137 C.elegans pri-miRNAs

ABSTRACT: Microprocessor (MP), cleaving primary microRNAs (pri-miRNAs) to initiate the biogenesis of thousands of miRNAs, was discovered in animals in 2004. Understanding the molecular mechanism of MP is critical for interpreting the gene-silencing roles of miRNAs in various cellular processes and human diseases. Though the molecular mechanism of human MP (hMP) has been comprehensively investigated for nearly two decades and is well understood, that of Caenorhabditis elegans MP (cMP, cDrosha-Pasha complex) is still unknown. In this study, we revealed a comprehensive molecular mechanism of cMP, distinctively from that of hMP. In the proposed mechanism, cDrosha and Pasha (DGCR8 in humans) measure ~16 bp and ~25 bp of the pri-miRNA stem, respectively, and they are coordinated in determining cleavage sites of cMP in pri-miRNAs. In addition, we also demonstrated the molecular basis for their substrate measurement. Our findings illustrate an unknown molecular mechanism of cMP, clarify differences between the mechanism of hMP and cMP, and provide a foundation for understanding multiple mechanisms regulating miRNA expression acting on cMP.

ORGANISM(S): Caenorhabditis elegans

PROVIDER: GSE212229 | GEO | 2023/01/23

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Similar Datasets

Genome wide identification of targets of the drosha-pasha/DGCR8 complex

Project description:Drosha is a type III RNAse, which plays a critical role in miRNA biogenesis. Drosha and its double-stranded RNA-binding partner protein Pasha/DGCR8 likely recognize and cleave miRNA precursor RNAs or pri-miRNA hairpins co-transcriptionally. To identify RNAs processed by Drosha, we used tiling microarrays to examine transcripts after depletion of drosha mRNA with dsRNA in Drosophila Schneider S2 cells. This strategy identified 137 Drosha-regulated RNAs, including 11 putative pri-miRNAs comprising 15 annotated miRNAs. Most of the identified pri-miRNAs seem extremely large, >10 kilobases as revealed by both the Drosha knock down strategy and by RNA PolII chromatin IP followed by Drosophila tiling microarrays. Surprisingly, more than a hundred additional RNAs not annotated as miRNAs are under Drosha control and are likely to be direct targets of Drosha action. This is because many of them encode annotated genes, and unlike bona fide pri-miRNAs, they are not affected by depletion of the miRNA processing factor, dicer-1. Moreover, application of the evofold analysis software indicates that at least 25 of the Drosha-regulated RNAs contain evolutionarily conserved hairpins similar to those recognized by the Drosha-Pasha/DGCR8 complex in pri-miRNAs. One of these hairpins is located in the 5′ UTR of both pasha and mammalian DGCR8. These observations suggest that a negative feedback loop acting on pasha mRNA may regulate the miRNA-biogenesis pathway: i.e., excess Drosha cleaves pasha/DGCR8 primary transcripts and leads to a reduction in pasha/DGCR8 mRNA levels and Pasha/DGCR8 synthesis. Keywords: time course, ChIP-chip

2008-12-25 | GSE14215 | GEO

The high-throughput pri-miRNA cleavage assays on 262144 variants

Project description:Microprocessor (MP), DROSHA-DGCR8, processes primary miRNA transcripts (pri-miRNAs) to initiate miRNA biogenesis. The canonical cleavage mechanism of MP has been extensively investigated and comprehensively validated for two decades. However, this canonical mechanism cannot account for the processing of certain pri-miRNAs in animals. In this study, by conducting high-throughput pri-miRNA cleavage assays for approximately 260,000 pri-miRNA sequences, we discovered and comprehensively characterized a noncanonical cleavage mechanism of MP. This noncanonical mechanism does not need several RNA and protein elements essential for the canonical mechanism; instead, it utilizes previously unrecognized DROSHA dsRNA recognition sites (DRES). Interestingly, the noncanonical mechanism is conserved across animals and plays a particularly significant role in C. elegans. Our established noncanonical mechanism elucidates MP cleavage in numerous RNA substrates unaccounted for by the canonical mechanism in animals. This study suggests a broader substrate repertoire of animal MPs and an expanded regulatory landscape for miRNA biogenesis.

2023-08-01 | GSE216012 | GEO

The SHAPE-MaP experiment to identify RNA structures of pri-mir-142 variants

Project description:MicroRNAs (miRNAs) are short non-coding RNAs that play essential roles in RNA silencing and gene regulation. The human Microprocessor (MP) is the key factor to initiate miRNA biogenesis by cleaving primary microRNAs (pri-miRNAs). However, the Microprocessor alone cannot precisely and efficiently cleave all pri-miRNAs; thus, it requires cofactors to assist its cleavage. SRSF3 interacts with CNNC in pri-miRNAs, enhancing the MP cleavage. However, it is unknown if SRSF3 can function with other non-CNNC motifs and if secondary structure might influce CNNC function. In addition, function of SRSF7, a paralog of SRSF3, in the SR proteins family, in miRNA biogenesis is largely unknown. In this study, by conducting the high-throughput pri-miRNA cleavage assays for the MP with SRSF3 or SRSF7 and randomized pri-miRNAs, we discovered that SRSF7 also stimulate MP clevage. Futhermore, we found that both SRSF3 and SRSF7 can function with some non-CNNC motifs and with CNNC motifs with certain secondary structures. Furthermore, we also demonstrated that SRSF7 and SRSF3 governed the cleavage sites of the Microprocessor in human cells. Our findings disclose the roles SRSF7 in miRNA biogenesis, demonstrate a compresenhive moleucalr mechanism of SFSF3 and SRSF7 in enhancing cleavage of MP and described in more detail the RNA-binding features of SRSF7 and SRSF3.

2023-01-23 | GSE221996 | GEO

Microprocessor recruitment to elongating RNA Polymerase II is required for differential expression of microRNAs

Project description:The cellular abundance of mature microRNAs (miRNAs) is dictated by the efficiency of nuclear processing of primary miRNA transcripts (pri-miRNAs) into pre-miRNA intermediates. The Microprocessor complex of Drosha and DGCR8 carries this out, but it has been unclear what controls Microprocessor's differential processing of various pri-miRNAs. Here, we show that Drosophila DGCR8 (Pasha) directly associates with the C terminal domain of the RNA polymerase II elongation complex when it is phosphorylated by the Cdk9 kinase (pTEFb). When association is blocked by loss of Cdk9 activity, a global change in pri-miRNA processing is detected. Processing of pri-miRNAs with a UGU sequence motif in their apical junction domain increases, while processing of pri-miRNAs lacking this motif decreases. Therefore, phosphorylation of RNA polymerase II recruits Microprocessor for co-transcriptional processing of non-UGU pri-miRNAs that would otherwise be poorly processed. In contrast, UGU-positive pri-miRNAs are robustly processed by Microprocessor independent of RNA polymerase association.

2017-09-15 | GSE103234 | GEO

A quantitative map of human primary microRNA processing sites

Project description:Maturation of canonical microRNA (miRNA) is initiated by DROSHA that cleaves the primary transcript (pri-miRNA). Over 1,800 miRNA loci are annotated in humans, but it remains largely unknown if and at which sites the pri-miRNAs are cleaved by DROSHA. Here we performed in vitro processing on a full set of human pri-miRNAs (miRBase v21) followed by sequencing. This comprehensive profiling enabled us to classify miRNAs based on DROSHA-dependence and map their cleavage sites with respective processing efficiency measures. Only 758 pri-miRNAs are confidently processed by DROSHA, while the majority may be non-canonical or false entries. Analyses of the DROSHA-dependent pri-miRNAs show key cis-elements for processing. We observe widespread alternative processing as well as unproductive cleavage events such as “nick” or “inverse” processing. SRSF3 is a broad-acting auxiliary factor modulating alternative processing and suppressing unproductive processing. The profiling data and methods developed in this study will allow systematic analyses of miRNA regulation.

2021-07-28 | PXD025767 | Pride

Microprocessor depends on hemin to recognize the apical loop of primary microRNA

Project description:Microprocessor, which consists of a ribonuclease III DROSHA and its cofactor DGCR8, initiates microRNA (miRNA) maturation by cleaving primary miRNA transcripts (pri-miRNAs). We recently demonstrated that the DGCR8 dimer recognizes the apical elements of pri-miRNAs, including the UGU motif, to accurately locate and orient Microprocessor on pri-miRNAs. However, the mechanism underlying the selective RNA binding remains unknown. In this study, we find that hemin, a ferric ion-containing porphyrin, enhances the specific interaction between the apical UGU motif and the DGCR8 dimer, allowing Microprocessor to achieve high efficiency and fidelity of pri-miRNA processing in vitro. Furthermore, by generating a DGCR8 mutant cell line and carrying out rescue experiments, we discover that hemin preferentially stimulates the expression of miRNAs possessing the UGU motif, thereby conferring differential regulation of miRNA maturation. Our findings reveal the molecular action mechanism of hemin in pri-miRNA processing and establish a novel function of hemin in inducing specific RNA-protein interaction.

2018-03-26 | GSE111431 | GEO

Regulation of Microprocessor assembly and localization via Pasha’s WW domain in C. elegans

Project description:Primary microRNA (pri-miRNA) transcripts are processed by a protein complex called the Microprocessor comprised of the ribonuclease Drosha and its RNA binding partner DGCR8/Pasha. We sequenced small RNAs from animals containing a mutation in the WW domain of C. elegans pash-1. We found that these mutants have a modest but widespread reduction in miRNA levels when grown at 20˚C, which is further enhanced when grown at 25˚C. The results demonstrate a requirement for the WW domain in processing miRNAs in C. elegans.

2024-04-16 | GSE263914 | GEO

The Interplay between K63-linked Polyubiquitinated DDX17 and m6A-modified miRNAs Regulates Hypoxia-induced Tumor Initiation

Project description:DEAD-box RNA-binding proteins (RBPs) play a significant role in RNA metabolism to achieve cellular homeostasis, including miRNA biogenesis and transcription. Hypoxia induces stemness cell-like characteristics in cancer cells and promotes malignant progression. Despite the fact that hypoxia can induce the changes in protein and RNA modification, thereby regulating downstream gene expressions, how modifications at different molecular layers interplay with each other are poorly understood. Here we show that hypoxia induces HectH9-mediated K63-linked polyubiquitination of the DEAD-box protein DDX17 as well as reduces N6-methyladenosine (m6A) marks in pri-miRNAs. While m6A potentiates DDX17 binding to pri-miRNAs, decreased m6A modifications of pri-miRNAs and increased polyubiquitination of DDX17 under hypoxia lead to decreased DDX17 binding to pri-miRNAs binding. These events enhance the association of DDX17 with the ubiquitin receptor p300 and lead to a decrease in miRNA biogenesis, especially for miRNAs regulating stemness and stemness-related genes. In addition, polyubiquitinated DDX17 together with p300 upregulates H3K56Ac levels on the stemness and stemness-related genes, resulting in enhancement of tumor initiating ability. Post-transcriptionally, decreased miRNA production, including those targeting stemness genes or stemness-related genes, also facilitates tumor initiation. Together, hypoxia triggers DDX17 poly-ubiquitination, which orchestrates dual mechanisms to increase tumor initiating ability and promote tumor progression.

2018-03-09 | PXD006059 | JPOST Repository

High-throughput SOLEXA sequencing of endogenous small RNAs from Arabidopsis thaliana wild-type

Project description:The length of Arabidopsis microRNA genes and their precursors (pri-miRNAs) can very between several hundreds bp to several thousands bp. They may contain introns, precursors may undergo alternative splicing, and often there are more than one polyadenylation site. An intriguing question arise: why to transcribe thousands of base pairs to produce a small RNA molecule of about 21 nt in length? We decided to sequence small RNAs from 35-day-old rosette leaves and to map the obtained reads of 18-26 nt in length to Arabidopsis pri-miRNAs. Our analyses revealed the presence of sRNAs that can derive only from miRNA precursors. An example is the identification of a substantial number of miR319b.2 reads. This sRNA is a product of pri-miR319b processing. Our further experimental analyses show that it carries multiple signatures of a functional microRNA 2 samples examined: wild type

2014-01-25 | E-GEOD-35335 | biostudies-arrayexpress

High-throughput SOLEXA sequencing of endogenous small RNAs from Arabidopsis thaliana wild-type

2014-01-25 | GSE35335 | GEO

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data