Gene-silencing activity of small RNAs controlled by TRMT6/61A-dependent base methylation
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE171040 | GEO | 2022/02/09
REPOSITORIES: GEO
Similar Datasets
Project description:Gene expression can be post-transcriptionally regulated via dynamic and reversible RNA modifications. N1-methyladenosine (m1A) is a recently identified mRNA modification; however, little is known about its precise location, regulation and function. Here, we develop a single-nucleotide resolution m1A profiling method, based on m1A-induced misincorporation during reverse transcription, and report distinct classes of m1A methylome in the human transcriptome. m1A in the 5’-untranslated region, particularly those located exactly at the first nucleotide of mRNA transcripts, associates with increased translation efficiency. A different subset of m1A sites exhibit a GUUCRA tRNA-like motif, are evenly distributed in the transcriptome and are dependent on the methyltransferase complex TRMT6/61A. Additionally, we show for the first time that m1A is prevalent in the mitochondrial-encoded transcripts. Manipulation of m1A level via TRMT61B, a mitochondria-localizing m1A methyltransferase, demonstrates that m1A in mitochondrial mRNA interferes with translation. Collectively, our approaches reveal distinct classes of m1A methylome and provide a resource for functional studies of m1A-mediated epitranscriptomic regulation.
2017-10-18 | GSE102040 | GEO
Project description:Increased protein translation plays a critical role in cancer development and treatment1,2. However, the molecular mechanism that is involved in this process remains poorly understood. N1-methyladenosine (m1A) methylation in RNA accounts for regulating mRNA translation in a post-transcriptional manner3,4. Here we show that m1A methylation levels are remarkably elevated in hepatocellular carcinoma (HCC) patient tumor tissues, especially in patients with microscopic vascular invasion (MVI). Moreover, m1A methylation signals are increased in liver cancer stem cells (CSCs) and are negatively correlated with HCC patient survival. Consistently, TRMT6 and TRMT61A, forming m1A methyltransferase complex, are highly expressed in advanced HCC tumors and are negatively correlated with HCC survival. TRMT6/TRMT61A-mediated m1A methylations are required for self-renewal of liver CSCs and tumorigenesis. Mechanistically, TRMT6/TRMT61A-dependent m1A in tRNA boost PPARδ expression, which triggers cholesterol synthesis to activate Hedgehog signaling, driving self-renewal of liver CSCs and tumorigenesis. For potential therapeutic benefit, we further identify a specific inhibitor against TRMT6/TRMT61A complex that exerts effective therapeutic effect on liver cancer with high m1A methylations. Our findings provide novel insights into the function and molecular mechanism of m1A modifications underlying liver tumorigenesis and drug target, which will serve as a new biomarker for HCC and pave a new way to develop more effective therapeutic strategies for HCC patients.
2021-03-01 | GSE147840 | GEO
Project description:N1-methyladenosine (m1A) is an abundant post-transcriptional RNA modification, yet little is known about its prevalence, topology and dynamics in mRNA. Here, we show that m1A is abundant in human mRNA, with an m1A/A ratio of ~0.02%. We develop m1A-ID-Seq, based on m1A immunoprecipitation and the inherent property of m1A to stall reverse transcription, for the transcriptome-wide m1A analysis. m1A-ID-Seq identifies 901 m1A peaks (from 583 genes) in mRNA and ncRNA, and reveals a prominent feature of enrichment in the 5â-untranslated region of mRNA transcripts, distinct from that of N6-methyladenosine, the most abundant internal mammalian mRNA modification. m1A in mRNA is also reversible by ALKBH3, a known DNA/RNA demethylase. Lastly, m1A responds dynamically to stimuli and hundreds of stress-induced m1A sites are identified. Collectively, our approaches allow comprehensive analysis of m1A methylation and provide an important tool for functional studies of potential epigenetic regulation via the reversible and dynamic m1A methylation. Identification of m1A sites in human embryonic kidney cells. Comparisons of m1A profiles of wild type HEK293T with ALKBH3 knock out cell line reveals the ALKBH3 specific sites. Stress inducible m1A sites are also identified by comparing the profiles of untreated cells with stress treated cells.
2016-02-05 | E-GEOD-73941 | biostudies-arrayexpress
Project description:N1-methyl adenosine (m1A) is a wide-spread RNA modification present in tRNA, rRNA and mRNA. m1A modification sites in tRNAs are evolutionary conserved and its formation on tRNA is catalyzed by methyltransferase TRMT61A and TRMT6 complex. m1A promotes translation initiation and elongation. Due to its positive charge under physiological conditions, m1A can notably modulate RNA structure. It also blocks Watson-Crick base pairing and causes mutation and truncation during reverse transcription. Several misincorporation-based high throughput sequencing methods have been developed to sequence m1A. In this study, we introduce a reduction-based m1A sequencing (red-m1A-seq). We report that NaBH4 reduction of m1A can improve the mutation and readthrough rates using commercially available RT enzymes to give better positive signature, while alkaline-catalyzed Dimroth rearrangement can efficiently convert m1A to m6A to provide good controls, allowing the detection of m1A with higher sensitivity and accuracy. We applied red‑m1A-seq to sequence human small RNA and we not only detected all the previously reported tRNA m1A sites, but also new m1A sites in mt-tRNAAsn-ATT and 5.8S rRNA.
2024-04-24 | GSE253657 | GEO
Project description:N1-methyladenosine (m1A) is one of messenger RNA modification in eukaryotes, but the potential roles of m1A methylated mRNA in trophoblast upon hypoxia remain elusive.
2020-03-24 | GSE135403 | GEO
Project description:To investigate the function of N1-methyladenosine methylome (m1A) in ocular melanoma, we analyzed m1A enrichment level in ocular melanoma and melanocyte cell lines and established ALKBH3 knock down cell lines in 92.1.
2022-09-22 | GSE213748 | GEO
Project description:N1-Methyladenosine (m1A) is a prevalent post-transcriptional RNA modification, yet little is known about its abundance, topol- ogy and dynamics in mRNA. Here, we show that m1A is prevalent in Homo sapiens mRNA, which shows an m1A/A ratio of ~0.02%. We develop the m1A-ID-seq technique, based on m1A immunoprecipitation and the inherent ability of m1A to stall reverse tran- scription, as a means for transcriptome-wide m1A profiling. m1A-ID-seq identifies 901 m1A peaks (from 600 genes) in mRNA and noncoding RNA and reveals a prominent feature, enrichment in the 5' untranslated region of mRNA transcripts, that is dis- tinct from the pattern for N6-methyladenosine, the most abundant internal mammalian mRNA modification. Moreover, m1A in mRNA is reversible by ALKBH3, a known DNA/RNA demethylase. Lastly, we show that m1A methylation responds dynamically to stimuli, and we identify hundreds of stress-induced m1A sites. Collectively, our approaches allow comprehensive analysis of m1A modification and provide tools for functional studies of potential epigenetic regulation via the reversible and dynamic m1A methylation.
2016-02-05 | GSE73941 | GEO
Project description:N1-methyladenosine (m1A) was recently identified as a new mRNA modification based on its mapping to the 5’UTRs of thousands of mRNAs with an m1A-binding antibody. More recent studies have questioned the prevalence of m1A. To address this discrepancy, we mapped m1A using ultra-deep RNA-Seq datasets based on m1A-induced misincorporations during reverse transcription. Using this approach, we find m1A only in the mitochondrial MT-ND5 transcript. In contrast, m1A mapping using an m1A-binding antibody showed binding to transcription start nucleotides in mRNA 5’UTRs. Biochemical measurements indicate that m1A is not present at these sites. Instead, we find that the m1A antibody exhibits m1A-independent binding to mRNA cap structures. Our data demonstrate that high-stoichiometry m1A sites are rare in the transcriptome and that previous mapping of m1A to mRNA 5’UTRs reflect an unintended binding to mRNA caps.
2019-06-23 | GSE97909 | GEO
Project description:Dinoflagellates, a class of unicellular eukaryotic phytoplankton, exhibit minimal transcriptional regulation, representing a unique model for exploring gene expression. The biosynthesis, distribution, regulation, and function of mRNA N1-methyladenosine (m1A) remain controversial due to its limited presence in typical eukaryotic mRNA. This study found that m1A, rather than N6-methyladenosine (m6A), is the most prevalent internal mRNA modification in various dinoflagellate species, with an asymmetrically distribution along mature transcripts. In Amphidinium carterae, we identified 6549 m1A sites characterized by a non-tRNA T-loop-like sequence motif within the transcripts of 3196 genes, many involved in regulating carbon and nitrogen metabolism. With enrichment within 3'UTR, dinoflagellate mRNA m1A exhibits negative correlation with translation efficiency. Notably, nitrogen depletion led to a significant decrease in mRNA m1A. Furthermore, our analysis revealed that distinctive patterns of m1A modification influence the expression of metabolism-related genes through translation control. Thus, this study provides a comprehensive map of m1A in dinoflagellate mRNA, highlighting its crucial role as a post-transcriptional regulatory layer and enhancing the understanding of mRNA m1A modification.
2024-07-30 | GSE271240 | GEO
Project description:Dinoflagellates, a class of unicellular eukaryotic phytoplankton, exhibit minimal transcriptional regulation, representing a unique model for exploring gene expression. The biosynthesis, distribution, regulation, and function of mRNA N1-methyladenosine (m1A) remain controversial due to its limited presence in typical eukaryotic mRNA. This study found that m1A, rather than N6-methyladenosine (m6A), is the most prevalent internal mRNA modification in various dinoflagellate species, with an asymmetrically distribution along mature transcripts. In Amphidinium carterae, we identified 6549 m1A sites characterized by a non-tRNA T-loop-like sequence motif within the transcripts of 3196 genes, many involved in regulating carbon and nitrogen metabolism. With enrichment within 3'UTR, dinoflagellate mRNA m1A exhibits negative correlation with translation efficiency. Notably, nitrogen depletion led to a significant decrease in mRNA m1A. Furthermore, our analysis revealed that distinctive patterns of m1A modification influence the expression of metabolism-related genes through translation control. Thus, this study provides a comprehensive map of m1A in dinoflagellate mRNA, highlighting its crucial role as a post-transcriptional regulatory layer and enhancing the understanding of mRNA m1A modification.
2024-07-30 | GSE246921 | GEO