関連する実験動画
Updated: Jun 3, 2026

09:12
DNAzyme-dependent Analysis of rRNA 2’-O-Methylation
Published on: September 16, 2019
RNAポリメラーゼIIのC端末ドメインは,サイト固有のメチル化によって変化する
Robert J Sims1, Luis Alejandro Rojas1, David B Beck1
1Howard Hughes Medical Institute (HHMI), Department of Biochemistry, New York University School of Medicine, 522 First Avenue, Smilow 211, New York, NY 10016, USA.
まとめ
RNAポリメラーゼII (RNAPII) のCTDメチル化は,R1810でのCARM1により,転写開始前に行われます. このメチル化は,特定の小さなRNAの発現に不可欠であり,遺伝子調節に影響を与えます.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝子発現の表現について
- 翻訳後の修正 翻訳後の修正
背景:
- RNAポリメラーゼII (RNAPII) のカルボキシ末端ドメイン (CTD) は,翻訳後に大きく変化している.
- これらの修正は,転写の開始と延長の調節に極めて重要です.
研究 の 目的:
- RNAPII CTD改変におけるアルギニンメチル化の役割を調査する.
- CTDメチル化に起因する特定の酵素とその機能的影響を特定する.
主な方法:
- RNAPII CTD.に対するCARM1の活性を決定するためのインビトロ酵素分析.
- RNAPIIにおけるR1810のサイト指向型変異.
- 野生型および変異細胞/線維芽細胞における小RNA発現の分析.
主要な成果:
- コアクティベーター関連アルギニンメチルトランスファーゼ1 (CARM1) は,アルギニン1810 (R1810) でRNAPII CTDをメチラする.
- メチル化は,ハイパーフォスホル化RNAPIIにインビョで発生するが,セル2/セル5のリン酸化によってインビョで抑制され,開始前のタイミングを示唆する.
- R1810変異またはCARM1欠乏は,小核RNAおよび小核RNAの誤発現につながる.
結論:
- R1810のCARM1によるCTDメチル化は,RNAPIIの新しい翻訳後の改変である.
- このメチル化イベントは,選択された小さなRNAの適切な発現に不可欠です.
- CTDメチル化は,異なる遺伝子型に対する特定の転写機構の採用に役割を果たす可能性があります.
関連する概念動画
Eukaryotic RNA Polymerases
RNA Polymerase (RNAP) is conserved in all animals, with bacterial, archaeal, and eukaryotic RNAPs sharing significant sequence, structural, and functional similarities. Among the three eukaryotic RNAPs, RNA Polymerase II is most similar to bacterial RNAP in terms of both structural organization and folding topologies of the enzyme subunits. However, these similarities are not reflected in their mechanism of action.
All three eukaryotic RNAPs require specific transcription factors, of which the...
All three eukaryotic RNAPs require specific transcription factors, of which the...
Eukaryotic RNA Polymerases
RNA Polymerase (RNAP) is conserved in all animals, with bacterial, archaeal, and eukaryotic RNAPs sharing significant sequence, structural, and functional similarities. Among the three eukaryotic RNAPs, RNA Polymerase II is most similar to bacterial RNAP in terms of both structural organization and folding topologies of the enzyme subunits. However, these similarities are not reflected in their mechanism of action.
All three eukaryotic RNAPs require specific transcription factors, of which the...
All three eukaryotic RNAPs require specific transcription factors, of which the...
Transcription Initiation
Initiation is the first step of transcription in eukaryotes. Prokaryotic RNA Polymerase (RNAP) can bind to the template DNA and start transcribing. On the other hand, transcription in eukaryotes requires additional proteins, called transcription factors, to first bind to the promoter region in the DNA template. This binding helps recruit the specific RNAP that can assemble on the DNA and start transcription.
The promoters and enhancers and their accessory proteins allow tight regulation of...
The promoters and enhancers and their accessory proteins allow tight regulation of...
RNA Polymerase II Accessory Proteins
Proteins that regulate transcription can do so either via direct contact with RNA Polymerase or through indirect interactions facilitated by adaptors, mediators, histone-modifying proteins, and nucleosome remodelers. Direct interactions to activate transcription is seen in bacteria as well as in some eukaryotic genes. In these cases, upstream activation sequences are adjacent to the promoters, and the activator proteins interact directly with the transcriptional machinery. For example, in...
RNA Polymerase II Accessory Proteins
Proteins that regulate transcription can do so either via direct contact with RNA Polymerase or through indirect interactions facilitated by adaptors, mediators, histone-modifying proteins, and nucleosome remodelers. Direct interactions to activate transcription is seen in bacteria as well as in some eukaryotic genes. In these cases, upstream activation sequences are adjacent to the promoters, and the activator proteins interact directly with the transcriptional machinery. For example, in...
Transfer RNA Synthesis
One of the unique features of tRNA is the presence of modified bases. In some tRNAs, modified bases account for nearly 20% of the total bases in the molecule. Altogether, these unusual bases protect the tRNA from enzymatic degradation by RNases.
Each of these chemical modifications is carried by a specific enzyme, post-transcription. All of these enzymes have unique base and site-specificity. Methylation, the most common chemical modification, is carried by at least nine different enzymes, with...
Each of these chemical modifications is carried by a specific enzyme, post-transcription. All of these enzymes have unique base and site-specificity. Methylation, the most common chemical modification, is carried by at least nine different enzymes, with...

