Transcriptome-wide analysis of roles for tRNA modifications in translational regulation
Ontology highlight
ABSTRACT:
ORGANISM(S): Saccharomyces cerevisiae
PROVIDER: GSE100626 | GEO | 2017/06/29
SECONDARY ACCESSION(S): PRJNA392312
REPOSITORIES: GEO
Similar Datasets
Project description:Diverse chemical modifications fine-tune the function and metabolism of tRNA. Although tRNA modification is universal in all kingdoms of life, profiles of modifications, their functions, and physiological roles have not been elucidated in most organisms including the human pathogen, Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis. To identify physiologically important modifications, we surveyed the tRNA of Mtb, using tRNA sequencing (tRNA-seq). Reverse transcription-derived error signatures in tRNA-seq predicted the sites and presence of 9 modifications. Several chemical treatments prior to tRNA-seq expanded the number of predictable modifications. Deletion of Mtb genes encoding two modifying enzymes, TruB and MnmA, eliminated their respective tRNA modifications, validating the presence of modified sites in tRNA species.
2023-08-11 | GSE240200 | GEO
Project description:The human genome encodes hundreds of tRNA genes but their individual contribution to the tRNA pool is not fully understood. Deep sequencing of tRNA transcripts (tRNA-Seq) can estimate tRNA abundance at single gene resolution, but tRNA structures and post-transcriptional modifications impair these analyses. Here we present a bioinformatics strategy to investigate differential tRNA gene expression and use it to compare tRNA-Seq datasets from cultured human cells and human brain. We find that sequencing caveats affect quantitation of only a subset of human tRNA genes. Unexpectedly, we detect several cases where the differences in tRNA expression among samples do not involve variations at the level of isoacceptor tRNA sets (tRNAs charged with the same amino acid but using different anticodons); but rather among tRNA genes within the same isodecoder set (tRNAs having the same anticodon sequence). Because isodecoder tRNAs are functionally equal in terms of genetic translation, their differential expression may be related to non-canonical tRNA functions. We show that several instances of differential tRNA gene expression result in changes in the abundance of tRNA-derived fragments (tRFs) but not of mature tRNAs. Examples of differentially expressed tRFs include: PIWI-associated RNAs, tRFs present in tissue samples but not in cells cultured in vitro, and somatic tissue-specific tRFs. Our data support that differential expression of tRNA genes regulate non-canonical tRNA functions performed by tRFs.
2019-04-17 | GSE114904 | GEO
Project description:tRNAs are heavily decorated with post-transcriptional modifications (tRNA modifications). Profile of tRNA modifications in non-model organisms are largely uncharacterized. Here using high-throughput sequencing, sites and frequency of tRNA modifications are predicted in Vibrio cholerae and Escherichia coli. During cDNA synthesis, some modifications cause misincorporation of a wrong base or termination of reverse transcription (RT). Using these RT-derived signatures we aim to explore organism-specific modifications and to track changes in modification frequency among different cellular conditions.
2020-05-15 | GSE147614 | GEO
Project description:Transfer RNA (tRNA) molecules contain a variety of post-transcriptional modifications which are crucial for tRNA stability, translation efficiency, and fidelity. Besides their canonical roles in translation, tRNAs also originate tRNA-derived small RNAs (tsRNAs), a class of small non-coding RNAs with regulatory functions ranging from translation regulation, to gene expression control and cellular stress response. Recent evidence show that tsRNAs are also modified, however the impact of tRNA epitranscriptome deregulation on tsRNAs generation is only now beginning to be uncovered. The 5-methyluridine (m5U) modification at position 54 of cytosolic tRNAs is one of the most common and conserved tRNA modifications among species. This modification is catalyzed by the tRNA methyltransferase TRMT2A, but its biological role remains largely unexplored. Here, we show that TRMT2A knockdown in human cells induces m5U54 tRNA hypomodification, resulting in angiogenin (ANG) dependent tsRNA formation. More specifically, m5U54 hypomodification is followed by ANG overexpression and tRNA cleavage near the anticodon, resulting in accumulation of 5’tRNA-derived stress-induced RNAs (5’tiRNAs), in particular 5’tiRNA-GlyGCC and 5’tiRNA-GluCTC. Additionally, transcriptomic analysis confirms that down-regulation of TRMT2A and consequently m5U54 hypomodification impacts the cellular stress response and RNA stability, which is often correlated with tsRNA generation. Accordingly, exposure to oxidative stress conditions induces TRMT2A down-regulation and tsRNA formation in mammalian cells. These results establish a link between tRNA demethylation and tsRNAs formation and unravel m5U54 as a tRNA cleavage protective mark.
2021-04-20 | GSE164168 | GEO
Project description:Transfer RNA (tRNA) molecules contain a variety of post-transcriptional modifications which are crucial for tRNA stability, translation efficiency, and fidelity. Besides their canonical roles in translation, tRNAs also originate tRNA-derived small RNAs (tsRNAs), a class of small non-coding RNAs with regulatory functions ranging from translation regulation, to gene expression control and cellular stress response. Recent evidence show that tsRNAs are also modified, however the impact of tRNA epitranscriptome deregulation on tsRNAs generation is only now beginning to be uncovered. The 5-methyluridine (m5U) modification at position 54 of cytosolic tRNAs is one of the most common and conserved tRNA modifications among species. This modification is catalyzed by the tRNA methyltransferase TRMT2A, but its biological role remains largely unexplored. Here, we show that TRMT2A knockdown in human cells induces m5U54 tRNA hypomodification, resulting in angiogenin (ANG) dependent tsRNA formation. More specifically, m5U54 hypomodification is followed by ANG overexpression and tRNA cleavage near the anticodon, resulting in accumulation of 5’tRNA-derived stress-induced RNAs (5’tiRNAs), in particular 5’tiRNA-GlyGCC and 5’tiRNA-GluCTC. Additionally, transcriptomic analysis confirms that down-regulation of TRMT2A and consequently m5U54 hypomodification impacts the cellular stress response and RNA stability, which is often correlated with tsRNA generation. Accordingly, exposure to oxidative stress conditions induces TRMT2A down-regulation and tsRNA formation in mammalian cells. These results establish a link between tRNA demethylation and tsRNAs formation and unravel m5U54 as a tRNA cleavage protective mark.
2021-04-20 | GSE164405 | GEO
Project description:Dynamic changes in tRNA modifications and abundance during T-cell activation [ncRNA-seq]
| PRJNA684568 | ENA
Project description:N7-methylguanosine (m7G) modification is one of the most prevalent tRNA modifications in human. The precise function and molecular mechanism of m7G tRNA modification in regulation of cancer remain poorly understood. Here we showed that m7G tRNA modification, METTL1 and WDR4 are elevated in hepatocellular carcinoma (HCC) tissues and associated with HCC patient prognosis. Functionally, silencing METTL1 or WDR4 inhibits HCC cell proliferation, migration and invasion, while forced expression of wild type METTL1 but not its catalytic dead mutant promotes HCC progression. Knockdown of METTL1 reduces m7G tRNA modification and decreases m7G modified tRNA expression. Mechanistically, METTL1 depletion selectively decreases the mRNA translation of a subset of oncogenic genes, especially cell cycle and EGFR pathway genes, in m7G-related codon dependent manner. Moreover, in vivo studies using Mettl1 knock-in and knockout mice reveal a critical function of Mettl1 mediated m7G tRNA modifications in promoting hepatocarcinogenesis in the hydrodynamics transfection HCC model. Our work uncovers the critical functions of tRNA m7G modification in regulating cancer mRNA translation and promoting hepatocarcinogenesis, thus provides new insights into role of the mis-regulated tRNA modifications in cancers.
2021-06-26 | GSE174492 | GEO
Project description:Profiling tRNA modifications in Mycobacterium tuberculosis
| PRJNA1002795 | ENA
Project description:Abstract: tRNAs are highly modified in the elbow region and harbor 5-methyluridine at position 54 and pseudouridine at position 55 in the T arm, which are generated by the enzymes TrmA and TruB, respectively. Although all elongator tRNAs contain these modifications across all domains of life, the cellular relevance of these modifications and their corresponding modifying enzymes remains elusive. In addition to modifying every tRNA, Escherichia coli TrmA and TruB have both been shown to fold tRNA independently of its modification activity acting as tRNA chaperones, and strains lacking trmA or truB are outcompeted by wildtype. To identify how TrmA and TruB contribute to cellular fitness, we have systematically assessed the effects of deleting trmA and/or trmB in E. coli. Since tRNA folding is a pre-requisite for tRNA aminoacylation, we determined cellular aminoacylation levels revealing a global decrease in aminoacylation for all tRNAs in ΔtrmA and ΔtruB. Moreover, the absence of 5-methyluridine 54 or pseudouridine 55 alters tRNA modification at other positions: whereas acp3U47 is decreased, thiouridine levels are increased. Understanding the importance of TrmA and TruB for tRNA aminoacylation and modification, we then analyzed how these global tRNA changes in ΔtrmA and ΔtruB strains affect translation. Whereas global protein synthesis is not significantly changed in ΔtrmA and ΔtruB, the abundances of many specific proteins are altered, and transcriptomics experiments suggest that the dysregulation of many proteins is controlled at the translational level. In conclusion, we demonstrate that universally conserved modifications of the tRNA elbow are critical for global tRNA function by enhancing other tRNA modifications, tRNA folding, tRNA aminoacylation and translation of specific genes thereby contributing to cellular fitness.
2023-05-31 | GSE233667 | GEO
Project description:Transfer RNAs (tRNA) are quintessential in deciphering the genetic code; disseminating nucleic acid triplets into correct amino acid identity. While this decoding function is clear, an emerging theme is that tRNA abundance and functionality can powerfully impact protein production rate, folding, activity, and messenger RNA stability. Importantly, however, the expression pattern of tRNAs (in even simple systems) is obliquely known. Limited analysis suggests tRNA levels change during proliferation, differentiation, cancer, and neurodegeneration; possibly mediating changes in translation efficiency and mRNA stability. A major limitation for the field has been the ability to subject tRNA pools to high-throughput analysis as they are highly structured, modified, and of high sequence similarity. Here we present Quantitative Mature tRNA sequencing (QuantM-tRNA seq), an easily implemented high-throughput technique to monitor tRNA abundance and sequence variants (possibly due to RNA modifications). With QuantM-tRNA seq we provide a comprehensive analysis of the tRNA transcriptome from distinct mammalian tissues. We observe dramatic distinctions in isodecoder expression and likely RNA modifications between unique tissues with a particularly strong signature within the central nervous system. Remarkably, despite dramatic changes in tRNA isodecoder gene expression, the overall anticodon pool of each tRNA family is similar. These findings suggest that anticodon pools are buffered via an unknown mechanism to achieve uniform decoding throughout the body.
2020-08-04 | GSE141436 | GEO