Project description:The field of epitranscriptomics is growing in importance, with chemical modification of RNA being associated with a wide variety of biological phenomena. Mass spectrometry (MS) enables the identification of modified RNA residues within their sequence contexts, by using analogous approaches to shotgun proteomics. We have developed a free and open-source database search engine for RNA MS data, called NucleicAcidSearchEngine (NASE), as part of the OpenMS software framework. NASE allows the reliable identification of (modified) RNA sequences from LC-MS/MS data in a high-throughput fashion. For this validation dataset, we generated samples of human total tRNA from a cellular extract - a complex mixture of highly modified RNAs. The samples were RNase-treated prior to nanoflow LC-MS/MS analysis.
Project description:The field of epitranscriptomics is growing in importance, with chemical modification of RNA being associated with a wide variety of biological phenomena. Mass spectrometry (MS) enables the identification of modified RNA residues within their sequence contexts, by using analogous approaches to shotgun proteomics. We have developed a free and open-source database search engine for RNA MS data, called NucleicAcidSearchEngine (NASE), as part of the OpenMS software framework. NASE allows the reliable identification of (modified) RNA sequences from LC-MS/MS data in a high-throughput fashion. For this validation dataset, we generated a sample of human total tRNA from a cellular extract - a complex mixture of highly modified RNAs. This sample was RNase-treated prior to nanoflow LC-MS/MS analysis.
Project description:The field of epitranscriptomics is growing in importance, with chemical modification of RNA being associated with a wide variety of biological phenomena. Mass spectrometry (MS) enables the identification of modified RNA residues within their sequence contexts, by using analogous approaches to shotgun proteomics. We have developed a free and open-source database search engine for RNA MS data, called NucleicAcidSearchEngine (NASE), as part of the OpenMS software framework. NASE allows the reliable identification of (modified) RNA sequences from LC-MS/MS data in a high-throughput fashion. For this validation dataset, oligonucleotides with the sequence of mature Drosophila let-7 microRNA, 21 nt in length, were produced synthetically in unmodified and modified (2’-O-methylated at the 3’ uridine) forms. We characterised a 1:1 mixture of both forms of this RNA.
Project description:The field of epitranscriptomics is growing in importance, with chemical modification of RNA being associated with a wide variety of biological phenomena. Mass spectrometry (MS) enables the identification of modified RNA residues within their sequence contexts, by using analogous approaches to shotgun proteomics. We have developed a free and open-source database search engine for RNA MS data, called NucleicAcidSearchEngine (NASE), as part of the OpenMS software framework. NASE allows the reliable identification of (modified) RNA sequences from LC-MS/MS data in a high-throughput fashion. For this validation dataset, we generated samples of human long ribosomal RNA from a cellular extract. The samples were RNase-treated prior to nanoflow LC-MS/MS analysis.
Project description:The field of epitranscriptomics is growing in importance, with chemical modification of RNA being associated with a wide variety of biological phenomena. Mass spectrometry (MS) enables the identification of modified RNA residues within their sequence contexts, by using analogous approaches to shotgun proteomics. We have developed a free and open-source database search engine for RNA MS data, called NucleicAcidSearchEngine (NASE), as part of the OpenMS software framework. NASE allows the reliable identification of (modified) RNA sequences from LC-MS/MS data in a high-throughput fashion. For this validation dataset, we prepared two samples of an in vitro-transcribed yeast lncRNA (NME1, 340 nt long), one of which was treated with an RNA methyltransferase (NCL1) catalyzing the 5-methylcytidine (m5C) modification. These samples were subsequently digested with an RNA endonuclease (RNase) to generate oligonucleotide sequences of a length amenable to mass spectrometry.
Project description:The field of epitranscriptomics is growing in importance, with chemical modification of RNA being associated with a wide variety of biological phenomena. Mass spectrometry (MS) enables the identification of modified RNA residues within their sequence contexts, by using analogous approaches to shotgun proteomics. We have developed a free and open-source database search engine for RNA MS data, called NucleicAcidSearchEngine (NASE), as part of the OpenMS software framework. NASE allows the reliable identification of (modified) RNA sequences from LC-MS/MS data in a high-throughput fashion. For this validation dataset, we prepared two samples of an in vitro-transcribed yeast lncRNA (NME1, 340 nt long), one of which was treated with an RNA methyltransferase (NCL1) catalyzing the 5-methylcytidine (m5C) modification. These samples were subsequently digested with an RNA endonuclease (RNase) to generate oligonucleotide sequences of a length amenable to mass spectrometry.
Project description:With the rapid growth of synthetic messenger RNA (mRNA)-based therapeutics and vaccines, the development of analytical tools for characterization of long, complex RNAs has become essential. Tandem liquid chromatography-mass spectrometry (LC-MS/MS) permits direct assessment of the mRNA primary sequence and modifications thereof without conversion to cDNA or amplification. It relies upon digestion of mRNA with site-specific endoribonucleases to generate pools of short oligonucleotides that are then amenable to MS-based sequence analysis. Here, we showed that the uridine-specific human endoribonuclease hRNase 4 improves mRNA sequence coverage, in comparison with the benchmark enzyme RNase T1, by producing a large population of uniquely mappable cleavage products. Furthermore, we deployed hRNase 4 to characterize mRNAs fully substituted with 1-methylpseudouridine (m1Ψ) or 5-methoxyuridine (mo5U), as well as mRNAs selectively depleted of uridine–two key strategies to reduce synthetic mRNA immunogenicity. Lastly, we demonstrated that hRNase 4 enables direct assessment of the 5′ cap incorporation in in vitro synthesized mRNA. Collectively, this study highlights the power of hRNase 4 to interrogate mRNA sequence, identity, and modifications by LC-MS/MS.
2022-07-26 | PXD033334 | Pride
Project description:Thiouridine profiling of E. coli tRNA
Project description:The RNA-Seq was used to analyze the expression profiling of genes in different ablescent stages of 'Anji Baicha' Examination of three tea leaf samples in yellow stage, white stage and green stage
Project description:Accurate translation of mRNAs into functional proteins is a fundamental process in all living organisms. In bacteria, in the early stage of translation elongation, peptidyl-tRNAs (pep-tRNAs) with short nascent chains frequently dissociate from the ribosome (pep-tRNA drop-off). The dissociated pep-tRNAs are deacylated and recycled by peptidyl-tRNA hydrolase (PTH), which is an essential enzyme in bacteria. Here, we establish a highly sensitive method for direct profiling of pep-tRNAs using RNA isolation method and mass spectrometry. We isolated each tRNA species with peptide from Escherichia coli pthts cells using reciprocal circulating chromatography and precisely analyzed their nascent peptides. As a result, we successfully detected 703 peptides consisted of 402 cognate peptides and 301 non-cognate peptides with single amino-acid substitution. Detailed analysis of individual pep-tRNAs revealed that most of the substitutions in the miscoded peptides take place at the C-terminal drop-off site. We further examined this observation using a reporter construct and found that the non-cognate pep-tRNAs produced by mistranslation rarely participate in the next round of elongation but dissociate from the ribosome, suggesting that pep-tRNA drop-off is an active mechanism by which the ribosome rejects miscoded pep-tRNAs in the early elongation, thereby contributing to quality control of protein synthesis after peptide bond formation.