Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Translational repression of NMD targets by GIGYF2 and EIF4E2

ABSTRACT: Translation of messenger RNAs (mRNAs) with premature translation termination codons produces truncated proteins with potentially deleterious effects. This is prevented by nonsense-mediated mRNA decay (NMD) of these mRNAs. NMD is triggered by ribosomes terminating upstream of a splice site marked by an exon-junction complex (EJC), but also acts on many mRNAs lacking a splice junction after their termination codon. We developed a genome-wide CRISPR flow cytometry screen to identify regulators of mRNAs with premature termination codons in K562 cells. This screen recovered essentially all core NMD factors and suggested a role for EJC factors in degradation of PTCs without downstream splicing. Among the strongest hits were the translational repressors GIGYF2 and EIF4E2. GIGYF2 and EIF4E2 mediate translational repression but not mRNA decay of a subset of NMD targets and interact with NMD factors genetically and physically. Our results suggest a model wherein recognition of a stop codon as premature can lead to its translational repression through GIGYF2 and EIF4E2.

INSTRUMENT(S): Q Exactive HF

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Permanent Cell Line Cell

SUBMITTER: Niladri Sinha

LAB HEAD: Rachel Green

PROVIDER: PXD027479 | Pride | 2021-10-12

REPOSITORIES: pride

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
	Figure6-RAW-files-indices.xlsx	Xlsx
	LD-QC-LE_201207_GreenR_NS_S10_20210129063811.mgf	Mgf
	LD-QC-LE_201207_GreenR_NS_S10_20210129063811.raw	Raw
	LD-QC-LE_201207_GreenR_NS_S11_20210129103048.mgf	Mgf
	LD-QC-LE_201207_GreenR_NS_S11_20210129103048.raw	Raw

Items per page:

1 - 5 of 28

Similar Datasets

Interactome of GIGYF2 and EIF4E2 with and without SMG1i treatement

Project description:Translation of messenger RNAs (mRNAs) with premature translation termination codons produces truncated proteins with potentially deleterious effects. This is prevented by nonsense-mediated mRNA decay (NMD) of these mRNAs. NMD is triggered by ribosomes terminating upstream of a splice site marked by an exon-junction complex (EJC), but also acts on many mRNAs lacking a splice junction after their termination codon. We developed a genome-wide CRISPR flow cytometry screen to identify regulators of mRNAs with premature termination codons in K562 cells. This screen recovered essentially all core NMD factors and suggested a role for EJC factors in degradation of PTCs without downstream splicing. Among the strongest hits were the translational repressors GIGYF2 and EIF4E2. GIGYF2 and EIF4E2 mediate translational repression but not mRNA decay of a subset of NMD targets and interact with NMD factors genetically and physically. Our results suggest a model wherein recognition of a stop codon as premature can lead to its translational repression through GIGYF2 and EIF4E2.

2021-10-12 | PXD027487 | Pride

Widespread EJC footprints in the RNA degradome mark mRNA degradation before steady-state translation

Project description:Exon junction complexes (EJCs) are deposited to mRNAs during splicing and displaced from mRNAs by ribosomes in the pioneer round of translation. The understanding of EJC-bound mRNA degradation before steady-state translation has been limited to nonsense-mediated mRNA decay (NMD) due to a lack of suitable methodologies. Here, we show that RNA degradome data of Arabidopsis, rice, worm and human cells all exhibit a predominant accumulation of 5′ monophosphate (5′P) ends in the canonical EJC region. Inhibition of 5′-3′ exoribonuclease activity and overexpression of an EJC disassembly factor in Arabidopsis reduced the 5′P ends accumulating in the EJC region, supporting the notion that these 5′P ends are in vivo EJC footprints. Hundreds of Arabidopsis NMD targets possess evident EJC footprints, validating their degradation during the pioneer round of translation. In addition to premature termination codons, plant microRNAs can also direct the degradation of EJC-bound mRNAs. However, the production of EJC footprints from NMD but not microRNA targets is dependent on an NMD factor, SMG7. Together, our finding demonstrating in vivo EJC footprinting unravels the composition of the RNA degradome, and provides a new avenue for studying NMD and other mechanisms, such as microRNAs, targeting EJC-bound mRNAs for degradation before steady-state translation.

2020-02-02 | GSE118215 | GEO

Nonsense-mediated mRNA decay in Tetrahymena is EJC independent and requires a protozoa-specific nuclease

Project description:Nonsense-mediated mRNA decay (NMD) is essential for removing premature termination codon (PTC)-containing transcripts from cells. Studying the NMD pathway in model organisms can help to elucidate the NMD mechanism of humans and improves our understanding of how this biologically important process has evolved. Protozoa are among the earliest branching eukaryotes. Their NMD mechanism is poorly understood and may be primordial. We demonstrate that highly conserved Upf proteins (Upf1a, Upf2, and Upf3) are involved in the NMD pathway of the ciliate, Tetrahymena thermophila. We further show that a novel protozoa-specific nuclease, Smg6L, is responsible for destroying many NMD-targeted transcripts. The transcriptome-wide identification and characterization of NMD-targeted transcripts in vegetative Tetrahymena cells showed that many have exon–exon junctions downstream of the termination codon. However, Tetrahymena homologs of exon junction complex (EJC) core components do not form a complex and are dispensable for NMD, suggesting that NMD is EJC independent in this early branching eukaryote.

2017-07-17 | GSE90899 | GEO

RNAi knock down of known nonsense-mediated mRNA decay (NMD) factors in Drosophila cells

Project description:All eukaryotes studied to date have the capacity to detect and degrade mRNAs harboring premature translation termination codons (PTCs) in a process called nonsense-mediated mRNA decay (NMD) (reviewed in Wagner E & Lykke-Andersen J, 2002). This surveillance system allows the cell to prevent the expression of potentially harmful truncated proteins. trans-acting factors required for NMD in Drosophila are the proteins UPF1, UPF2, UPF3, SMG-1, SMG-5 and SMG-6. To identify mRNAs naturally regulated by NMD, we analyzed expression profiles in Drosophila cells RNAi-depleted of known NMD factors using high-density oligonucleotide arrays.

2005-11-01 | E-MEXP-202 | biostudies-arrayexpress

Regulated endocleavage balances the degradation of nonsense-mediated decay substrates

Project description:Nonsense-mediated mRNA decay (NMD) controls gene expression by eliminating mRNAs with premature or aberrant translation termination. Degradation of NMD substrates is initiated by the central NMD factor UPF1, which recruits the endonuclease SMG6 and the deadenylation-promoting SMG5/7 complex. Here we map transcriptome-wide sites of SMG6-mediated endocleavage via 3′ fragment capture and degradome sequencing.

2017-06-01 | E-MTAB-3625 | biostudies-arrayexpress

Genome-wide consequences of compromised NMD and their relavence for variable clinical phenotype of patients with UPF3B mutations [CNV]

Project description:Nonsense-mediated mRNA decay (NMD) surveillance pathways are best known to be involved in the degradation of mRNA with premature termination codons (PTCs). More recent studies demonstrate that the role of NMD pathways goes well beyond the degradation of PTC containing mRNA, into the regulation of cell function and thus normal development. We have taken advantage of the availability of naturally occurring loss of function mutations in the UPF3B gene, a major component of the exon junction complex (EJC), to inquire about genome-wide consequences of compromised NMD. We identify that about 5% of the lymphoblastoid cell transcriptome is directly or indirectly impacted upon in patients with UPF3B mutations with minimal effect on alternative splicing. We identify UPF3A-NMD as a likely, major modifier of the UPF3B patient phenotype through variable UPF3A protein stabilisation. Among the most consistently deregulated direct targets of UPF3B-NMD we identify the ARHGAP24 as the most likely gene implicated in the neuronal phenotype of UPF3B patients. To assess the impact of UPF3B-NMD deficiency on human transcriptome, we sequenced polyA RNA extracted from lymphoblastoid cell lines of patients (n=4) and controls (n=2). We complemented the analysis using Affymetrix Human Exon 1.0 St array using total RNA of the same cell line from patients (n=5, 3 of whom were also sequenced) and controls (n=5). Moreover, we overlapped identified differently expressed genes with copy number variation data of the patients, obtained using Illumina Human Omniexpress chip, to exclude possible false positive.

2011-11-01 | E-GEOD-27412 | biostudies-arrayexpress

Genome-wide consequences of compromised NMD and their relavence for variable clinical phenotype of patients with UPF3B mutations [mRNA profiling]

2011-11-01 | E-GEOD-27125 | biostudies-arrayexpress

Ribosome-bound Upf1 forms distinct 80S complexes and conducts mRNA surveillance

Project description:Upf1, Upf2, and Upf3 are the central regulators of nonsense-mediated mRNA decay (NMD), the eukaryotic mRNA quality control pathway generally triggered when a premature termination codon is recognized by the ribosome. The NMD-related functions of the Upf proteins likely commence while these factors are ribosome-associated, but little is known of the timing of their ribosome binding, their specificity for ribosomes translating NMD substrates, or the nature and role of any ribosome:Upf complexes. Here, we have elucidated details of the ribosome-associated steps of NMD. By combining yeast genetics with selective ribosome profiling and co-sedimentation analyses of polysomes with wild-type and mutant Upf proteins, our approaches have identified distinct states of ribosome:Upf association. All three Upf factors manifest progressive polysome association as mRNA translation proceeds, but these events appear to be preceded by formation of a Upf1:80S complex as mRNAs initiate translation. This complex is likely executing an early mRNA surveillance function.

2022-10-21 | PXD029577 | Pride

Identification of NMD regulated genes in Nicotiana benthamiana

Project description:Nonsense mediated decay (NMD) is a translation termination coupled quality control system. NMD identifies and degrades aberrant mRNAs containing premature termination codons, thereby preventing the accumulation of detrimental truncated proteins. NMD also controls the expression of several normal mRNAs and non-coding transcripts. RNA-seq assays were conducted to identify the NMD regulated genes in Arabidopsis. However, NMD targets have not been studied in other plants. To identify the conserved NMD targets, we wanted to identify the NMD regulated genes in Nicotiana benthamiana model species. Virus induced gene silencing was used to inactivate UPF1 NMD key factor in N. benthamiana, and then comparative RNA-seq experiment was carried out using UPF1-silenced and control–silenced plants. We found that in N. benthamiana significantly more genes are controlled by NMD than in Arabidopsis and that, surprisingly few conserved NMD targets can be recognized. These results suggest that while the mechanism of NMD is highly conserved, the set of NMD controlled genes can be quickly changed in plants.

2019-07-01 | GSE109130 | GEO

Nanopore sequencing reveals endogenous NMD-targeted isoforms in human cells

Project description:Nonsense-mediated mRNA decay (NMD) is a eukaryotic, translation-dependent degradation pathway that targets mRNAs with premature termination codons and also regulates the expression of some mRNAs that encode full-length proteins. Although many genes express NMD-sensitive transcripts, identifying them based on short-read sequencing data remains a challenge. To identify and analyze endogenous targets of NMD, we applied cDNA Nanopore sequencing and short-read sequencing to human cells with varying expression levels of NMD factors. Our approach detects full-length NMD substrates that are highly unstable and increase in levels or even only appear when NMD is inhibited. Among the many new NMD-targeted isoforms that our analysis identified, most derive from alternative exon usage. The isoform-aware analysis revealed many genes with significant changes in splicing but no significant changes in overall expression levels upon NMD knockdown. NMD-sensitive mRNAs have more exons in the 3΄UTR and for mRNAs with a termination codon in the last exon. The length of the 3΄UTR per se does not correlate with NMD sensitivity. Analysis of splicing signals reveals isoforms where NMD has been co-opted in the regulation of gene expression, but a main function is most likely to rid the transcriptome of isoforms resulting from spurious splicing events. Long-read sequencing enabled the identification of many novel NMD-sensitive mRNAs and revealed both known and unexpected features concerning their biogenesis and their biological role. Our data provide a highly valuable resource of human NMD transcript targets for future genomic and transcriptomic applications.

2021-07-20 | E-MTAB-10452 | biostudies-arrayexpress