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Updated: May 12, 2026

11:42
Iterative Optimization of DNA Duplexes for Crystallization of SeqA-DNA Complexes
Published on: November 1, 2012
ラムダ抑制器のC端末ドメインの結晶構造は,協力的なオペレーター結合のモデルを提供します
C E Bell1, P Frescura, A Hochschild
1The Johnson Foundation and Department of Biochemistry and Biophysics, University of Pennsylvania School of Medicine, Philadelphia 19104, USA.
Cell
|July 13, 2000
まとめ
この研究は,ラムダ・レプレッサーによる協力的なDNA結合の構造的基礎を明らかにしています. 結晶構造は,2つの抑制ダイマーが相互作用して隣接するオペレータサイトを結合し,遺伝子調節を説明する方法を示しています.
科学分野:
- 分子生物学は分子生物学である.
- 構造生物学 構造生物学とは
- 遺伝学 遺伝学とは
背景:
- 転写因子による協力的なDNA結合は,遺伝子調節に極めて重要です.
- この協力関係を説明する詳細な構造モデルは,しばしば欠けています.
- ラムダ抑制器 (c1) は,協同結合を研究するためのモデルシステムです.
研究 の 目的:
- ラムダ抑制器のC端領域のX線結晶構造を決定する.
- 協力的なDNA結合を媒介する分子相互作用を解明する.
- 2つのラムダ圧縮器ディマーを隣接するオペレーターサイトに結合するための構造モデルを開発する.
主な方法:
- X線結晶グラフィーです.
- 多波長異常 difraktion (MAD) とは,多波長異常 difraktion (MAD) と呼ばれるものです.
- 構造的,遺伝的,生化学的なデータの統合.
主要な成果:
- ラムダ・リプレッサーC端末ドメインの結晶構造が決定されました.
- この構造は,協働性に関与する2次元の相互作用を捉えた.
- 2つの抑制ダイマーが,対称性の2倍軸の周りに結合することが観察されました.
結論:
- この構造は,ラムダ抑制器結合における協同性を理解するための分子基礎を提供する.
- この研究は,転写因子の協力性の一般的なメカニズムについての洞察を提供します.
- 隣接するオペレーター・サイトに2つのラムダ・リプレッサー・ディマーを協力的に結合させるモデルが提案されています.
関連する概念動画
Operons
Prokaryotes can control gene expression through operons—DNA sequences consisting of regulatory elements and clustered, functionally related protein-coding genes. Operons use a single promoter sequence to initiate transcription of a gene cluster (i.e., a group of structural genes) into a single mRNA molecule. The terminator sequence ends transcription. An operator sequence, located between the promoter and structural genes, prohibits the operon’s transcriptional activity if bound by a repressor...
Cooperative 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...
Co-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...
Cooperative 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...
Co-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...
Operon Model
The operon model represents a fundamental mechanism of gene regulation in prokaryotes, enabling coordinated expression of genes involved in related metabolic or functional pathways. Operons consist of structural genes, a promoter, and an operator, with transcription regulated by repressors, activators, and small effector molecules.Structure and Function of OperonsAn operon is a cluster of structural genes transcribed together under the control of a single promoter. The promoter region...

