在单个细胞中,在单个分子水平上进行静态蛋白质表达
Long Cai1, Nir Friedman, X Sunney Xie
1Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, USA.
Nature
|March 17, 2006
概括
这项研究引入了一种微流体测试,用于实时,单分子观察活细胞中的基因表达. 检测显示,蛋白质的产生发生在爆发,使得低复制数蛋白质的特征.
科学领域:
- 细胞和分子生物学 细胞和分子生物学
- 生物物理学的生物物理.
- 系统生物学 系统生物学
背景情况:
- 由于分子数量低,活细胞中的基因表达本质上是随机的.
- 在非同步的细胞群体中,观察单个蛋白质生产事件是具有挑战性的.
- 现有的单细胞测量方法缺乏灵敏度来解决离散的蛋白质生产事件.
研究的目的:
- 开发一种用于实时,单分子观察单个细胞基因表达的敏感试验.
- 研究蛋白质生产的动态,特别关注类似爆发的事件.
- 为了证明该试验在不同细胞类型中的适用性,以研究低丰度蛋白质.
主要方法:
- 开发一种基于微流体的测定方法,使实时监测成为可能.
- 单分子灵敏度,用于观察大肠杆菌中的β-银酸酶表达.
- 测试对发芽酵母和小鼠胚胎干细胞的应用.
主要成果:
- 证明了基因表达的实时单分子观测.
- 观察到蛋白质的生产发生在随机爆发.
- 描述了爆发大小和频率,显示了爆发大小的指数分布.
- 展示了测试在原生细胞和真核细胞的普遍性.
结论:
- 微流体检测提供了前所未有的实时,单分子解析基因表达动态.
- 蛋白质生产的特点是爆发,具有可量化的参数,如爆发大小和频率.
- 这种技术对于研究目前的基因组和蛋白质组方法无法访问的低拷贝数蛋白质至关重要.
- 该试验的广泛适用性有助于在各种生物系统中对基因表达的全系统表征.
相关概念视频
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...
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...
02:24Ribosome Profiling
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Applications of ribosome profiling
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The technique helps...
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...
01:19Protein Dynamics in Living Cells
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01:23Regulation of Expression at Multiple Steps
The gene expression in cells is regulated at different stages: (i) transcription, (ii) RNA processing, (iii) RNA localization, and (iv) translation. Transcriptional regulation is mediated by regulatory proteins such as transcription factors, activators, or repressors—these control gene expression by initiating or inhibiting the transcription of genes. Once a precursor or pre-mRNA is produced, it undergoes post-transcriptional modification, including 5' capping, splicing, and the addition of a...