基失活调节嗅觉受体基因表达的作用
1Department of Biochemistry and Molecular Biophysics, College of Physicians and Surgeons, Columbia University, New York, New York 10032.
Cell
|September 9, 1994
概括
一个新的模型解释了单个感觉神经元如何从一个大家族中仅表达一个气味受体基因. 这通过控制DNA水平的基因表达来确保精确的气味检测.
科学领域:
- 遗传学 是一个遗传学.
- 神经科学是一个神经科学.
- 分子生物学分子生物学
背景情况:
- 感觉神经元通过表达特定的气味受体 (OR) 蛋白来检测气味.
- 一个单个神经元通常只表达来自大量基因家族 (哺乳动物大约1000个) 的一种OR类型.
- 确保这种单基因表达的精确机制仍然不完全理解.
研究的目的:
- 提出并支持一个模型,解释单个嗅觉受体在感觉神经元中的基因表达的分子机制.
- 为了阐明神经元如何从一个庞大的目录中选择和表达单一的功能性OR基因.
主要方法:
- 该研究提出了一个基于现有的遗传和分子生物学原理的模型.
- 它整合了关于 cis 调节元件,随机基因表达,等位基因排除和异步DNA复制的观察.
- 该模型从观察到的基因表达和等位基因活性模式中推断出机制.
主要成果:
- 一个控制层次结构调节了气味受体基因的表达.
- 一个cis调节元件被提议用于从链接数组中指导单个基因的随机表达.
- 表达仅限于一个等位基,与与等位基失活相关的异步复制有关.
结论:
- 拟议的模型解释了个体感官神经元如何实现单元和单元特异性气味受体表达.
- 这种机制涉及对单个活性等位基数组的cis-regulatory控制和对另一个基因基数组的无活化.
- 这保证了个体神经元的可靠和特定的气味检测.
相关概念视频
01:08Allosteric Regulation
Allosteric regulation of enzymes occurs when the binding of an effector molecule to a site that is different from the active site causes a change in the enzymatic activity. This alternate site is called an allosteric site, and an enzyme can contain more than one of these sites. Allosteric regulation can either be positive or negative, resulting in an increase or decrease in enzyme activity. Most enzymes that display allosteric regulation are metabolic enzymes involved in the degradation or...
01:08Allosteric Regulation
Allosteric regulation of enzymes occurs when the binding of an effector molecule to a site that is different from the active site causes a change in the enzymatic activity. This alternate site is called an allosteric site, and an enzyme can contain more than one of these sites. Allosteric regulation can either be positive or negative, resulting in an increase or decrease in enzyme activity. Most enzymes that display allosteric regulation are metabolic enzymes involved in the degradation or...
02:04Co-activators and Co-repressors
Gene transcription is regulated by the synergistic action of several proteins that form a complex at a gene regulatory site. This is observed in eukaryotes, where the regulation of gene expression is a complex process. Regulatory proteins in eukaryotes can broadly be classified into two types – regulators that bind directly to specific DNA sequences and co-regulators that associate with regulatory proteins but cannot directly bind to the DNA. These co-regulators are further divided into...
01:52Eukaryotic Transcription Inhibitors
Certain biochemical processes, such as embryonic development and cell growth regulation, depend on the repression of specific genes. DNA binding proteins known as eukaryotic transcription inhibitors regulate the repression of gene expression in eukaryotes. The presence of these inhibitors at the required location and time in the cell is triggered by the presence of hormones and additional signals from other cells.
Eukaryotic transcription inhibitors usually contain two distinct domains, a DNA...
Eukaryotic transcription inhibitors usually contain two distinct domains, a DNA...
02:04Co-activators and Co-repressors
Gene transcription is regulated by the synergistic action of several proteins that form a complex at a gene regulatory site. This is observed in eukaryotes, where the regulation of gene expression is a complex process. Regulatory proteins in eukaryotes can broadly be classified into two types – regulators that bind directly to specific DNA sequences and co-regulators that associate with regulatory proteins but cannot directly bind to the DNA. These co-regulators are further divided into...
01:27Constitutive and Regulated Gene Expression
Gene expression in prokaryotes is governed by constitutive and regulated systems, allowing cells to balance the production of essential proteins with adaptive responses to environmental changes.Constitutive Gene ExpressionConstitutive, or housekeeping, genes are continuously expressed as they encode proteins vital for fundamental cellular processes. These include enzymes for glycolysis, ribosomal components for protein synthesis, and proteins involved in DNA replication. Their constant...