Structure-function analysis of microRNA 3′-end trimming by Nibbler
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA663864 | ENA |
REPOSITORIES: ENA
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| SRR12653266.fastq.gz | Fastqsanger.gz | |||
| SRR12653267.fastq.gz | Fastqsanger.gz | |||
| SRR12653268.fastq.gz | Fastqsanger.gz | |||
| SRR12653269.fastq.gz | Fastqsanger.gz |
Items per page: 5 1 - 4 of 4 |
Similar Datasets
Project description:Nibbler (Nbr) is a 3′-to-5′exoribonuclease whose catalytic 3′-end trimming activity impacts miRNA and piRNA biogenesis. Here, we report on structural and functional studies to decipher the contributions of Nbr’s N-terminal (NTD) and exonucleolytic (EXO) domains in miRNA 3′-end trimming. We have solved the crystal structures of the NTD-core and EXO domains of Nbr, both in the apo-state. The NTD-core domain of Aedes aegypti Nbr adopts a HEAT-like repeat scaffold, with basic patches constituting an RNA-binding surface exhibiting a preference for binding dsRNA over ssRNA. Structure-guided functional assays in DrosophilaS2 cells confirmed a principal role of the NTD in exonucleolytic miRNA trimming, that depends on basic surface patches.Gain-of-function experiments revealed a potential role of the NTD in recruitingNbr to Argonaute-bound small RNA substrates.The EXO domain of Aedes aegypti and Drosophila melanogaster Nbr adopt a mixed a/b scaffold with a deep pocket lined by a DEDDy catalytic cleavage motif. We demonstrate that Nbr’sEXO domain exhibits Mn2+-dependent ssRNA-specific 3′-to-5′exoribonuclease activity. Modeling of a 3′ terminal Uridine in to the catalytic pocket of Nbr EXO indicates that 2′-O-methylation of the 3′-U would result in a steric clash with a Tryptophanside chain, suggesting that 2′-O-methylation protects small RNAs from Nbr-mediated trimming. Overall, our data establish that Nbr requires its NTD as a substrate recruitment platform to execute exonucleolytic miRNA maturation, catalyzed by the ribonuclease domain.
2020-09-17 | GSE158054 | GEO
Project description:microRNAs (miRNAs) are typically generated as ~22-nucleotide double-stranded RNAs via processing of precursor hairpins by the RNase III enzyme Dicer, after which they are loaded into Argonaute (Ago) proteins to form RNA-induced silencing complex (RISC). However, the biogenesis of miR-451, an erythropoietic miRNA conserved in vertebrates, does not require Dicer processing. Instead, the short pre-miR-451 precursor hairpin is directly loaded into Ago, followed by cleavage of the 3' arm and trimming of the 3' end to the mature length by PARN. Here we show the in vivo activity of miR-430 Ago2-hairpin, a canonical microRNA engineered to fit the structure of miR-451 and hence become Ago2-dependent. Moreover, we test a modified miR-430 Ago2-haipin with 3x phoshorothioate bonds that impairs trimmng. Surprisingly, our data show that trimming of Ago-cleaved pre-miRNAs is not essential for target silencing, indicating that RISC is functional with miRNAs longer than 22-nucleotides.
2013-11-13 | GSE51036 | GEO
Project description:microRNAs (miRNAs) are typically generated as ~22-nucleotide double-stranded RNAs via processing of precursor hairpins by the RNase III enzyme Dicer, after which they are loaded into Argonaute (Ago) proteins to form RNA-induced silencing complex (RISC). However, the biogenesis of miR-451, an erythropoietic miRNA conserved in vertebrates, does not require Dicer processing. Instead, the short pre-miR-451 precursor hairpin is directly loaded into Ago, followed by cleavage of the 3' arm and trimming of the 3' end to the mature length by PARN. Here we show the in vivo activity of miR-430 Ago2-hairpin, a canonical microRNA engineered to fit the structure of miR-451 and hence become Ago2-dependent. Moreover, we test a modified miR-430 Ago2-haipin with 3x phoshorothioate bonds that impairs trimmng. Surprisingly, our data show that trimming of Ago-cleaved pre-miRNAs is not essential for target silencing, indicating that RISC is functional with miRNAs longer than 22-nucleotides. Rescue of MZdicer zebrafish mutant with the injection of trimmable and nontrimmable miR-430 Ago2 hairpins: Transcriptome of wild type, MZdicer mutant, and MZdicer mutant micoinjected with miR-430 duplex, miR-430 (Ago2-haripin), miR-430 (Ago2-haripin 3xPhosphorothioate)
2013-11-13 | E-GEOD-51036 | biostudies-arrayexpress
Project description:Nibbler (Nbr) is a 3'-to-5' exoribonuclease whose catalytic 3'-end trimming activity impacts microRNA (miRNA) and PIWI-interacting RNA (piRNA) biogenesis. Here, we report on structural and functional studies to decipher the contributions of Nbr's N-terminal domain (NTD) and exonucleolytic domain (EXO) in miRNA 3'-end trimming. We have solved the crystal structures of the NTD core and EXO domains of Nbr, both in the apo-state. The NTD-core domain of Aedes aegypti Nbr adopts a HEAT-like repeat scaffold with basic patches constituting an RNA-binding surface exhibiting a preference for binding double-strand RNA (dsRNA) over single-strand RNA (ssRNA). Structure-guided functional assays in Drosophila S2 cells confirmed a principal role of the NTD in exonucleolytic miRNA trimming, which depends on basic surface patches. Gain-of-function experiments revealed a potential role of the NTD in recruiting Nbr to Argonaute-bound small RNA substrates. The EXO domain of A. aegypti and Drosophila melanogaster Nbr adopt a mixed α/β-scaffold with a deep pocket lined by a DEDDy catalytic cleavage motif. We demonstrate that Nbr's EXO domain exhibits Mn2+-dependent ssRNA-specific 3'-to-5' exoribonuclease activity. Modeling of a 3' terminal Uridine into the catalytic pocket of Nbr EXO indicates that 2'-O-methylation of the 3'-U would result in a steric clash with a tryptophan side chain, suggesting that 2'-O-methylation protects small RNAs from Nbr-mediated trimming. Overall, our data establish that Nbr requires its NTD as a substrate recruitment platform to execute exonucleolytic miRNA maturation, catalyzed by the ribonuclease EXO domain.
| S-EPMC7720153 | biostudies-literature
Project description:MicroRNAs (miRNAs) act in concert with Argonaute (AGO) proteins to broadly repress mRNA targets. After AGO loading, miRNAs generally exhibit slow turnover. An important exception occurs when miRNAs encounter targets with extensive complementarity, which can trigger a process termed target-directed microRNA degradation (TDMD). Prevailing models of TDMD invoke miRNA tailing and trimming as an essential step in the decay mechanism. Here, a genome-wide screen revealed a novel cullin-RING ubiquitin ligase, which we named the DECAY complex, that mediates TDMD. The DECAY complex interacts with AGO proteins, mediates TDMD induced by multiple transcripts, and does not require tailing and trimming to elicit miRNA turnover. Based upon these findings, we propose a model in which the DECAY complex mediates TDMD by promoting proteasomal decay of miRNA-containing complexes.
2020-11-13 | GSE151516 | GEO
Project description:MicroRNAs (miRNAs) act in concert with Argonaute (AGO) proteins to broadly repress mRNA targets. After AGO loading, miRNAs generally exhibit slow turnover. An important exception occurs when miRNAs encounter targets with extensive complementarity, which can trigger a process termed target-directed microRNA degradation (TDMD). Prevailing models of TDMD invoke miRNA tailing and trimming as an essential step in the decay mechanism. Here, a genome-wide screen revealed a novel cullin-RING ubiquitin ligase, which we named the DECAY complex, that mediates TDMD. The DECAY complex interacts with AGO proteins, mediates TDMD induced by multiple transcripts, and does not require tailing and trimming to elicit miRNA turnover. Based upon these findings, we propose a model in which the DECAY complex mediates TDMD by promoting proteasomal decay of miRNA-containing complexes.
2020-11-13 | GSE151396 | GEO
Project description:MicroRNAs (miRNAs) act in concert with Argonaute (AGO) proteins to broadly repress mRNA targets. After AGO loading, miRNAs generally exhibit slow turnover. An important exception occurs when miRNAs encounter targets with extensive complementarity, which can trigger a process termed target-directed microRNA degradation (TDMD). Prevailing models of TDMD invoke miRNA tailing and trimming as an essential step in the decay mechanism. Here, a genome-wide screen revealed a novel cullin-RING ubiquitin ligase, which we named the DECAY complex, that mediates TDMD. The DECAY complex interacts with AGO proteins, mediates TDMD induced by multiple transcripts, and does not require tailing and trimming to elicit miRNA turnover. Based upon these findings, we propose a model in which the DECAY complex mediates TDMD by promoting proteasomal decay of miRNA-containing complexes.
2020-11-13 | GSE158025 | GEO
Project description:A ubiquitin ligase mediates target-directed microRNA decay independently of tailing and trimming
| PRJNA636177 | ENA
Project description:The structure of broken DNA ends is a critical determinant of the pathway used for DNA double strand break (DSB) repair. Here, we develop an approach, hairpin capture of DNA end structures (HCoDES), which elucidates chromosomal DNA end structures at single nucleotide resolution. HCoDES defines structures of physiologic DSBs generated by the RAG endonuclease, as well as those generated by nucleases widely used for genome editing. Analysis of G1-phase cells deficient in H2AX or 53BP1 reveals DNA ends that are frequently resected to form long single-stranded overhangs that can be repaired by mutagenic pathways. In addition to 3’ overhangs, many of these DNA ends unexpectedly form long 5’ single-stranded overhangs. The divergence in DNA end structures resolved by HCoDES suggests that H2AX and 53BP1 may have distinct activities in end protection. Thus, the high-resolution end structures obtained by HCoDES identify new features of DNA end processing during DSB repair.
2014-12-03 | GSE62534 | GEO
Project description:A ubiquitin ligase mediates target-directed microRNA decay independently of tailing and trimming [TDMD]
| PRJNA636178 | ENA