固有の酵母遺伝子の転写開始と延長をリアルタイムで観察する
Daniel R Larson1, Daniel Zenklusen, Bin Wu
1Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
Science (New York, N.Y.)
|April 23, 2011
まとめ
研究者は,酵母遺伝子の単一RNAポリメラーゼ活性を観察するための新しい方法を開発しました. 彼らは,遺伝子転写の開始には記憶がなく,延長速度が変化し,因子検索時間が遺伝子発射率を制御することを発見しました.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
- バイオフィジックス 生物物理学
背景:
- 細胞のメッセンジャーRNA (mRNA) レベルは,複合的な転写調節の結果である.
- 小分子経路におけるストキャスティックな変動は,遺伝子発現のダイナミクスの理解を複雑にする.
- 固有遺伝子の単一ポリメラーゼ活性 in vivo の観察は,実験的に困難でした.
研究 の 目的:
- 活性酵母ロカスにおける新生RNAの動態を観察する方法を開発し,適用する.
- 転写の開始,延長,終了のインビボメカニズムを解明する.
- 転写因子ダイナミクスと遺伝子発現率との関係を調査する.
主な方法:
- 光で標識されたRNAの変動分析.
- 固有の酵母遺伝子の新生RNAダイナミクスのリアルタイム観察.
- 上流の転写因子の豊富さと核内移動性の測定.
主要な成果:
- この研究では,新生RNAの開始,延長,終了のダイナミクスを測定することに成功しました.
- 個々の遺伝子イニシエーションイベントの間に転写記憶は観察されなかった.
- 伸長速度は,細胞サイクル全体で3倍の変動を示した.
- 遺伝子発射速度は,トランス活性化因子検索時間と直接相関することが判明しました.
結論:
- 開発された方法は,内生的な遺伝子における単一ポリメラーゼの活性をリアルタイムで観察することを可能にします.
- イーストの遺伝子転写の開始は,記憶のない独立したイベントです.
- 転写因子検索ダイナミクスは,遺伝子発現レベルを決定する重要な要因です.
関連する概念動画
01:47Transcription 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...
02:11Reporter Genes
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Commonly used reporter...
Commonly used reporter...
02:35Transcription Elongation Factors
Transcription elongation is a dynamic process that alters depending upon the sequence heterogeneity of the DNA being transcribed. Hence, it is not surprising that the elongation complex's composition also varies along the way while transcribing a gene.
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 into a...
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 into a...
02:35Transcription Elongation Factors
Transcription elongation is a dynamic process that alters depending upon the sequence heterogeneity of the DNA being transcribed. Hence, it is not surprising that the elongation complex's composition also varies along the way while transcribing a gene.
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 into a...
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 into a...
01:28Yeast Signaling
Yeasts are single-celled organisms, but unlike bacteria, they are eukaryotes (cells with a nucleus). Cell signaling in yeast is similar to signaling in other eukaryotic cells. A ligand, such as a protein or a small molecule released from a yeast cell, attaches to a receptor on the cell surface. The binding stimulates second-messenger kinases to activate or inactivate transcription factors that further regulate gene expression. Many of the yeast intracellular signaling cascades have similar...
02:24Ribosome Profiling
Ribosome profiling or ribo-sequencing is a deep sequencing technique that produces a snapshot of active translation in a cell. It selectively sequences the mRNAs protected by ribosomes to get an insight into a cell’s translation landscape at any given point in time.
Applications of ribosome profiling
Ribosome profiling has many applications, including in vivo monitoring of translation inside a particular organ or tissue type and quantifying new protein synthesis levels.
The technique helps...
Applications of ribosome profiling
Ribosome profiling has many applications, including in vivo monitoring of translation inside a particular organ or tissue type and quantifying new protein synthesis levels.
The technique helps...