生きている細胞の遺伝子発現を,一度に1つのタンパク質分子を検知する
1Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA.
Science (New York, N.Y.)
|March 18, 2006
まとめ
科学者は,Escherichia coli.で単一のタンパク質の生成を直接観察しました. タンパク質分子は,単一のメッセンジャーRNA分子の爆発で作られ,遺伝子発現の洞察を明らかにします.
科学分野:
- 分子生物学は分子生物学である.
- 微生物学 微生物学とは
- バイオフィジックス 生物物理学
背景:
- 遺伝子発現は基本的な生物学的プロセスです.
- 単一分子レベルでタンパク質の生産を理解することは,細胞メカニズムを解読する上で極めて重要です.
- 以前の研究では,個々の細胞の低レベルのタンパク質合成をリアルタイムで観察する解像度が不足していました.
研究 の 目的:
- 個々のEscherichia coli細胞の単一のタンパク質の生産をリアルタイムで直接視覚化し,定量化します.
- 突発生成と複製数分布を含むタンパク質合成のダイナミクスを調査する.
- 遺伝子発現を研究するために単一分子検出の有用性を実証する.
主な方法:
- 融合タンパク質を構成した: 膜を標的とするペプチドを備えた,迅速に成熟する黄色い光タンパク質 (YFP).
- 抑制された条件下でEscherichia coliの融合タンパク質を表現した.
- タンパク質生産をリアルタイムで観察するために,膜局所化されたYFPの単分子感受性検出を使用しました.
主要な成果:
- 個々のEscherichia coli.で単一のタンパク質分子の生産をリアルタイムで直接観察した.
- タンパク質分子が爆発的に生成されることを発見しました.
- それぞれの爆発は,単一の,ストキャスティックに転写されたメッセンジャーRNA分子から発生します.
- バスト内のタンパク質コピー数は,幾何学的な分布に従います.
結論:
- 単一分子実験は,基本的な生物学的プロセスに対する強力な定量的な洞察を提供します.
- タンパク質の生産は,単一のmRNA分子のストキャスティックトランスクリプションによって駆動され,爆発的に発生します.
- この研究は,単一分子アプローチが,生きている細胞における低レベルの遺伝子発現のメカニズムを明らかにする可能性を強調しています.
関連する概念動画
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...
02:11Reporter Genes
Reporter genes are a type of protein-coding gene that are often tagged to a gene of interest. Once inside a target cell, reporter genes usually produce visually identifiable characteristics like fluorescence and luminescence when expressed along with the gene of interest. Thus, reporter genes “report” the presence or absence of genes of interest in an organism, determine the gene expression pattern, or track the physical location of a DNA segment or protein in the cell.
Commonly used reporter...
Commonly used reporter...
01:19Protein 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...
02:34DNA Microarrays
Microarrays are high-throughput and relatively inexpensive assays that can be automated to analyze large quantities of data at a time. They are used in genome-wide studies to compare gene or protein expression under two varied conditions, such as healthy and diseased states. Microarrays consist of glass or silica slides on which probe molecules are covalently attached through surface functionalization. Most commonly, the slides are prepared through the chemisorption of silanes to silica...
01:42What is Gene Expression?
Overview
Gene expression is the process in which DNA directs the synthesis of functional products, that is, proteins. Cells can regulate gene expression at various stages. It allows organisms to generate different cell types and enables cells to adapt to internal and external factors.
Genetic Information Flows from DNA to RNA to Protein
A gene is a stretch of DNA that serves as the blueprint for functional RNAs and proteins. Since DNA is made up of nucleotides and proteins consist of amino...
Gene expression is the process in which DNA directs the synthesis of functional products, that is, proteins. Cells can regulate gene expression at various stages. It allows organisms to generate different cell types and enables cells to adapt to internal and external factors.
Genetic Information Flows from DNA to RNA to Protein
A gene is a stretch of DNA that serves as the blueprint for functional RNAs and proteins. Since DNA is made up of nucleotides and proteins consist of amino...
01:36What is Gene Expression?
A gene is a stretch of DNA that serves as the blueprint for functional RNAs and proteins. Since DNA is comprised of nucleotides and proteins are comprised of amino acids, a mediator is required to convert the information encoded in DNA into proteins. This mediator is the messenger RNA (mRNA). mRNA copies the blueprint from DNA by a process called transcription. In eukaryotes, transcription occurs in the nucleus by complementary base-pairing with the DNA template. The mRNA is then processed and...