タンパク質Id:ヘリックス・ループ・ヘリックスDNA結合タンパク質の負の調節体
R Benezra1, R L Davis, D Lockshon
1Department of Genetics, Fred Hutchinson Cancer Research Center, Seattle, Washington 98104.
Cell
|April 6, 1990
まとめ
新しいヘリックス・ループ・ヘリックス (HLH) タンパク質,Idは,DNA結合領域を欠いている. Idは他のHLHタンパク質を阻害し,細胞の分化を調節する役割を示唆しています.
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:
- ヘリックス・ループ・ヘリックス (HLH) タンパク質は,遺伝子発現の重要な調節因子である.
- HLHドメインに隣接する基本領域は,MyoDのようなタンパク質におけるDNA結合に不可欠である.
研究 の 目的:
- 新しいHLHタンパク質を特徴付けるには,Id.
- DNA結合と遺伝子調節におけるIdの機能を調査する.
主な方法:
- cDNAクローンとインビトロトランスレーション.
- タンパク質アソシエーションアッセイ.
- 細胞系におけるRNA発現分析.
- 遺伝子トランス活性化に対するIDの影響を評価するためのトランスフェクション実験.
主要な成果:
- 新しいHLHタンパク質であるIdが分離され,DNA結合の基本領域が欠けています.
- Idタンパク質は,他のHLHタンパク質 (MyoD,E12,E47) と結合し,DNA結合能力を阻害する.
- Id発現は,特定の細胞系の末端分化時に減少する.
- Idの過剰発現は,筋肉のクレアチンキナーゼ増強剤のMyoD媒介のトランス活性化を阻害する.
結論:
- idは,他のHLHタンパク質の支配負調節剤として作用する.
- 基本領域が欠けているHLHタンパク質は,HLHタンパク質の機能を否定的に調節する可能性があります.
- Idは,細胞の分化プロセスを制御する上で重要な役割を果たす可能性があります.
関連する概念動画
01:23Negative Regulator Molecules
Positive regulators allow a cell to advance through cell cycle checkpoints. Negative regulators have an equally important role as they terminate a cell’s progression through the cell cycle—or pause it—until the cell meets specific criteria.
02:13Cooperative Binding of Transcription Regulators
Transcriptional regulators bind to specific cis-regulatory sequences in the DNA to regulate gene transcription. These cis-regulatory sequences are very short, usually less than ten nucleotide pairs in length. The short length means that there is a high probability of the exact same sequence randomly occurring throughout the genome. Since regulators can also bind to groups of similar sequences, this further increases the chances of random binding. Transcriptional regulators form dimers that...
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...
02:13Cooperative Binding of Transcription Regulators
Transcriptional regulators bind to specific cis-regulatory sequences in the DNA to regulate gene transcription. These cis-regulatory sequences are very short, usually less than ten nucleotide pairs in length. The short length means that there is a high probability of the exact same sequence randomly occurring throughout the genome. Since regulators can also bind to groups of similar sequences, this further increases the chances of random binding. Transcriptional regulators form dimers that...
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...