関連する実験動画
Updated: Jul 23, 2026

11:22
Measuring the Kinetics of mRNA Transcription in Single Living Cells
Published on: August 25, 2011
生きている細胞の核における単一のmRNPの動態
Yaron Shav-Tal1, Xavier Darzacq, Shailesh M Shenoy
1Departments of Anatomy and Structural Biology and Cell Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
まとめ
シングルメッセンジャーRNA-タンパク質複合体 (mRNP) は,哺乳類細胞の核内での単純な拡散によって移動する. 彼らの動きはクロマチンによって制約され,指向されず,核mRNPの密輸のための拡散モデルをサポートしています.
科学分野:
- 分子生物学は分子生物学である.
- 細胞生物学 細胞生物学
- 遺伝学 遺伝学とは
背景:
- 遺伝子発現を理解するには,個々のRNA分子を追跡する必要があります.
- 生体細胞におけるメッセンジャーRNA-タンパク質複合体 (mRNP) のリアルタイムモニタリングは極めて重要です.
- 過去の研究では,核 mRNP 輸送のメカニズムについて議論されてきた.
研究 の 目的:
- 生きている哺乳類の細胞の核内の単一のmRNPのリアルタイム移動を特徴付ける.
- mRNPのモビリティが誘導的かランダム (拡散的) かを判断する.
- mRNPの移動に対する原子力環境とエネルギー状態の影響を調査する.
主な方法:
- メッセンジャーRNA (mRNA) の発現をモニタリングするためのセルラーシステムを利用しました.
- 核内の単一のmRNPの動きをリアルタイムで追跡した.
- エネルギー不足の条件下および異なる核環境で観察されたmRNPの行動.
主要な成果:
- 核内のmRNPの移動性は,直接的な動きではなく,単純な拡散によって支配されていることが判明しました.
- mRNPは,特定の亜核領域に蓄積することなく,非均質な核環境で部分的な腐食を示した.
- エネルギー剥奪の後,mRNPはATPに依存する核の中でATPから独立して移動し,染色素に乏しい領域に限定され,染色素バリアによって排除されます.
結論:
- 核 mRNP の密輸は,拡散モデルと一致しています.
- mRNP運動のエネルギー要求は,受動的拡散と一致しています.
- クロマチン構造はバリアとして作用し,核内のmRNPの空間的分布に影響を与えます.
関連する概念動画
Regulated mRNA Transport
In eukaryotes, transcription and translation are compartmentalized; an mRNA is first synthesized in the nucleus and then selectively transported to the cytoplasm for protein synthesis. Before transport, a pre-mRNA undergoes several steps of post-transcriptional modifications including splicing, 5' capping, and the addition of a poly-adenine tail. Various proteins bind to the pre-mRNA during these modifications. The mRNA transport takes place with the help of multiple proteins playing specific...
Directionality of Nuclear Transport
Ras-related nuclear protein or Ran is a small G protein that cycles between its GTP and GDP bound states. Ran specific regulators, a Ran GTPase Activating Protein or RanGAP present in the cytosol and a Ran guanine nucleotide exchange factor or RanGEF present inside the nucleus regulate GTP/GDP exchange. A high concentration of GTP inside the cells, in addition to this asymmetric distribution of Ran-specific regulators, leads to a higher RanGTP concentration inside the nucleus. This...
Non-equilibrium in the Cell
An important concept in studying metabolism and energy is that of chemical equilibrium. Most chemical reactions are reversible. They can proceed in both directions, releasing energy into their environment in one direction, and absorbing it from the environment in the other direction. The same is true for the chemical reactions involved in cell metabolism, such as the breaking down and building up of proteins into and from individual amino acids, respectively. Reactants within a closed system...
Atomic Nuclei: Magnetic Resonance
The number of nuclear spins aligned in the lower energy state is slightly greater than those in the higher energy state. In the presence of an external magnetic field, as the spins precess at the Larmor frequency, the excess population results in a net magnetization oriented along the z axis. When a pulse or a short burst of radio waves at the Larmor frequency is applied along the x axis, the coupling of frequencies causes resonance and flips the nuclear spins of the excess population from the...
Protein Dynamics in Living Cells
Different fluorescence-based techniques are used to study the protein dynamics in living cells. These techniques include FRAP, FRET, and PET.
Fluorescent recovery after photobleaching (FRAP) is a fluorescent-protein-based detection technique used to quantify protein movement rates within the cell. This method exposes a small portion of the cell to an intense laser beam. The laser beam causes permanent photobleaching of the fluorophore-tagged proteins in the exposed region. As the bleached...
Fluorescent recovery after photobleaching (FRAP) is a fluorescent-protein-based detection technique used to quantify protein movement rates within the cell. This method exposes a small portion of the cell to an intense laser beam. The laser beam causes permanent photobleaching of the fluorophore-tagged proteins in the exposed region. As the bleached...
Atomic Nuclei: Types of Nuclear Relaxation
Nuclear relaxation restores the equilibrium population imbalance and can occur via spin–lattice or spin–spin mechanisms, which are first-order exponential decay processes.
In spin–lattice or longitudinal relaxation, the excited spins exchange energy with the surrounding lattice as they return to the lower energy level. Among several mechanisms that contribute to spin–lattice relaxation, magnetic dipolar interactions are significant. Here, the excited nucleus transfers energy to a nearby...
In spin–lattice or longitudinal relaxation, the excited spins exchange energy with the surrounding lattice as they return to the lower energy level. Among several mechanisms that contribute to spin–lattice relaxation, magnetic dipolar interactions are significant. Here, the excited nucleus transfers energy to a nearby...

