Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Codon usage influences the local rate of translation elongation to regulate co-translational protein folding

ABSTRACT: Codon usage bias is a universal feature of eukaryotic and prokaryotic genomes and has been proposed to regulate translation efficiency, accuracy and protein folding based on the assumption that codon usage affects translation dynamics. The role of codon usage in regulating translation, however, is not clear and has been challenged by recent ribosome profiling studies. Here we used a Neurospora cell-free translation system to directly monitor the velocity of mRNA translation. We demonstrated that the use of preferred codons enhances the rate of translation elongation, whereas non-optimal codons slow translation. In addition, codon usage regulates ribosome traffic on the mRNA. These conclusions were supported by ribosome profiling results in vitro and in vivo with substrate mRNAs manipulated to increase signal over background noise. We further show that codon usage plays an important role in regulating protein function by affecting co-translational protein folding. Together, these results resolve a long-standing fundamental question and demonstrate the importance of codon usage on protein folding.

ORGANISM(S): Neurospora crassa

PROVIDER: GSE71032 | GEO | 2015/07/18

SECONDARY ACCESSION(S): PRJNA290152

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

The anti-Shine-Dalgarno sequence drives translational pausing and codon choice in bacteria

Project description:Protein synthesis by ribosomes takes place on a linear substrate but at variable speeds. Transient pausing of ribosomes can impact a variety of co-translational processes, including protein targeting and folding. These pauses are influenced by the sequence of the mRNA. Thus redundancy in the genetic code allows the same protein to be translated at different rates. However, our knowledge of both the position and the mechanism of translational pausing in vivo is highly limited. Here we present a genome-wide analysis of translational pausing in bacteria using ribosome profiling-deep sequencing of ribosome-protected mRNA fragments. This approach enables high-resolution measurement of ribosome density profiles along most transcripts at unperturbed, endogenous expression levels. Unexpectedly, we found that codons decoded by rare tRNAs do not lead to slow translation under nutrient-rich conditions. Instead, Shine-Dalgarno-(SD) like features within coding sequences cause pervasive translational pausing. Using an orthogonal ribosome possessing an altered anti-SD sequence, we demonstrated that pausing is due to hybridization between mRNA and the 16S rRNA of the translating ribosome. In protein coding sequences, internal SD sequences are disfavoured, which leads to biased usage, avoiding codons and codon pairs that resemble canonical SD sites. Our results indicate that internal SD-like sequences are a major determinant of translation rates and a global driving force for the coding of bacterial genomes. Identification of translation pause sites in vivo using ribosome profiling

2012-04-01 | E-GEOD-35641 | biostudies-arrayexpress

Optimization of codon translation rates via tRNA modifications maintains proteome integrity

Project description:Proteins begin to fold as they emerge from translating ribosomes. The kinetics of ribosome transit along a given mRNA can influence nascent chain folding, but the extent to which individual codon translation rates impact proteome integrity remains unknown. Here, we show that slower decoding of discrete codons elicits widespread protein aggregation in vivo. Using ribosome profiling, we find that loss of anticodon wobble uridine (U34) modifications in a subset of tRNAs leads to ribosome pausing at their cognate codons in S. cerevisiae and C. elegans. Yeast cells lacking U34 modifications exhibit gene expression hallmarks of proteotoxic stress and accumulate aggregates of endogenous proteins with key cellular functions. Moreover, these cells are severely compromised in clearing stress-induced protein aggregates. Overexpression of hypomodified tRNAs alleviates ribosome pausing, concomitantly restoring protein homeostasis. Our findings demonstrate that modified U34 is an evolutionarily conserved accelerator of decoding and reveal an unanticipated role for tRNA anticodon modifications in maintaining proteome integrity. Ribosome profiling of wild-type and tRNA modification-deficient yeast and nematodes. Yeast samples were generated in various growth conditions (rich medium versus stress induced by treatment with diamide or rapamycin) and paired mRNA-Seq was performed on a subset of samples. Dataset contains three biological replicates for yeast samples and two biological replicates for nematode samples.

2015-06-04 | E-GEOD-67387 | biostudies-arrayexpress

Modeling ribosome dwell times and relationship with tRNA loading and codon usage in mammals (Ribosome Profiling)

Project description:Protein translation depends on mRNA-specific initiation, elongation, and termination rates. While the regulation of ribosome elongation is well studied in bacteria and yeast, less is known in higher eukaryotes. Here, we combined ribosome and tRNA profiling to investigate the relations between ribosome elongation rates, (aminoacyl-) tRNA levels and codon usage in mammals. We modeled codon-specific ribosome dwell times and translation fluxes from ribosome profiling, considering pair-interactions between ribosome sites. In mouse liver, the model revealed site and codon specific dwell times, as well as codon pair-interactions clustering by amino acids. While translation fluxes varied significantly across diurnal time and feeding regimen, codon dwell times were highly stable, and conserved in human. Fasting had no effect on codon dwell times in mouse liver. Profiling of total and aminoacylated tRNAs revealed highly heterogeneous levels with specific isoacceptor patterns and a correlation with codon usage. tRNAs for isoleucine, asparagine, aspartate and arginine were lowly loaded and conserved in fasted mice. Finally, codons with low levels of charged tRNAs and high codon usage relative to tRNA abundance exhibited long dwell times. Together, these analyses pave the way towards understanding the complex relation between tRNA loading, codon usage and ribosome dwell times in mammals.

2020-03-26 | GSE126383 | GEO

Modeling ribosome dwell times and relationship with tRNA loading and codon usage in mammals (tRNA Profiling)

2020-03-26 | GSE126382 | GEO

Codon usage optimization in pluripotent embryonic stem cells [tRNA sequencing]

Project description:The uneven use of synonymous codons in the transcriptome regulates the efficiency and fidelity of protein translation rates. Yet, the importance of this codon bias on regulating cell state-specific expression programs is currently debated. Here, we asked whether the gene expression program in the well-defined cell states of self-renewal and differentiation in embryonic stem cells is driven by optimized codon usage. Using ribosome and transcriptome profiling, we identified distinct codon signatures for human self-renewing and differentiating embryonic stem cells. One driver for the cell state-specific codon bias was the genomic GC-content of the differentially expressed genes and thus, determined by transcription rather than translation. However, by measuring the codon frequencies at the ribosome’s active sites interacting with transfer RNAs (tRNA), we discovered that the wobble position tRNA modification inosine strongly influenced the codon optimization in self-renewing embryonic stem cells. This effect was conserved in mice and independent of the differentiation stimulus. In summary, we newly reveal how translational mechanisms based on RNA modifications can shape optimized codon usage in embryonic stem cells.

2019-05-17 | GSE123608 | GEO

Codon usage optimization in pluripotent embryonic stem cells [RNA-seq]

2019-05-17 | GSE112085 | GEO

Stop Codon Context Influences Genome-Wide Stimulation of Termination Codon Readthrough by Aminoglycosides [Dataset 4]

Project description:Stop codon readthrough (SCR) occurs when the ribosome miscodes at a stop codon. Such readthrough events can be therapeutically desirable when a premature termination codon (PTC) is found in a critical gene. To study SCR in vivo in a genome-wide manner, we treated mammalian cells with aminoglycosides and performed ribosome profiling. We find that in addition to stimulating readthrough of PTCs, aminoglycosides stimulate readthrough of normal termination codons (NTCs) genome-wide. Stop codon identity, the nucleotide following the stop codon, and the surrounding mRNA sequence context all influence the likelihood of SCR. In comparison to NTCs, downstream stop codons in 3′UTRs are recognized less efficiently by ribosomes, suggesting that targeting of critical stop codons for readthrough may be achievable without general disruption of translation termination. Finally, we find that G418 treatment globally alters gene expression with substantial effects on translation of histone genes, selenoprotein genes, and S-adenosylmethionine decarboxylase (AMD1).

2020-01-14 | GSE138641 | GEO

Stop Codon Context Influences Genome-Wide Stimulation of Termination Codon Readthrough by Aminoglycosides [Dataset 3]

2020-01-14 | GSE138640 | GEO

Stop Codon Context Influences Genome-Wide Stimulation of Termination Codon Readthrough by Aminoglycosides [Dataset 2]

2020-01-14 | GSE138639 | GEO

Stop Codon Context Influences Genome-Wide Stimulation of Termination Codon Readthrough by Aminoglycosides [Dataset 5]

2020-01-14 | GSE138642 | GEO