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Osmium Tag for Post-transcriptionally Modified RNA
Turja Kanti Debnath1, Akimitsu Okamoto1,2
1Department of Advanced Interdisciplinary Studies, Graduate School of Engineering, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo, 153-8904, Japan.
Abstract:
5-Methylcytidine (m5 C) and 5-methyluridine (m5 U) are highly abundant post-transcriptionally modified nucleotides that are observed in various natural RNAs. Such nucleotides were labeled through a chemical approach, as both underwent oxidation at the C5=C6 double bond, leading to the formation of osmium-bipyridine complexes, which could be identified by mass spectrometry. This osmium tag made it possible to distinguished m5 C and m5 U from their isomers, 2'-O-methylcytidine and 2'-O-methyluridine, respectively. Queuosine and 2-methylthio-N6 -isopentenyladenosine in tRNA were also tagged through complex formation.
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01:10Transcription
Transcription is the process of synthesizing RNA from a DNA sequence by RNA polymerase. It is the first step in producing a protein from a gene sequence. Additionally, many other proteins and regulatory sequences are involved in the proper synthesis of messenger RNA (mRNA). Regulation of transcription is responsible for the differentiation of all the different types of cells and often for the proper cellular response to environmental signals.
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02:36Transfer RNA Synthesis
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The transcription elongation is regulated via pausing of RNA polymerase on several occasions during transcription. In bacteria, these halts are necessary because the transcription of DNA into mRNA is coupled to the translation of that mRNA...
02:42Eukaryotic Transcription Activators
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