DNA修復複合体のダイナミックアーキテクチャとメオティック再結合の場所におけるシナプトネマ複合体
Alexander Woglar1, Anne M Villeneuve1
1Departments of Developmental Biology and Genetics, Stanford University School of Medicine, Stanford, CA, USA.
Cell
|May 15, 2018
まとめ
ミオティック・ダブル・ストランド・ブレイク (DSB) の修復は,ゲノムの完全性にとって極めて重要です. シナプトネマル複合体 (SC) は,非CO修復を保証しながら,クロスオーバー (CO) を促進して,DSB修復結果を調節する可能性があります.
科学分野:
- 遺伝学
- 細胞生物学
- 分子生物学
背景:
- MEIOTIC リコンビネーションは,二重鎖断裂 (DSB) の正確な修復に依存しています.
- クロスオーバー (CO) 形成を保証し,同時に非CO修復を通じてゲノムの完全性を維持することが不可欠です.
- シナプトネマル複合体 (SC) はメオシスに作用するが,DSB修復におけるその正確な機能は完全に理解されていない.
研究 の 目的:
- 微分化中のDSB修復複合体の動的構造を調査する.
- DSBの修復中間物質とシナプトネマル複合体 (SC) の関係を理解する.
- クロスオーバー (CO) サイトと非COサイトで異なる修復結果を制御するメカニズムを明らかにする.
主な方法:
- 構造照明顕微鏡を用いて,DSBの修復複合体を視覚化しました.
- 再結合部位におけるタンパク質局所化 (BLMヘリケーズ,RPA,MutSγ) の動的変化が追跡された.
- 修復中介物質とSCの空間的および時間的関係を分析した.
主要な成果:
- 切断されたDSBは,異なるタンパク質集団 (BLM,RPA,MutSγ) のインターホモログ修復中間物質を形成する.
- これらの中間物質はCOと非CO部位で異なるタンパク質ダイナミクスを持つ,遅いパキテンまで蓄積する.
- CO部位はSCタンパク質に包まれ,第2のMutSγ集団を獲得し,RPAを失い,COの成熟にSCの関与を示唆する.
結論:
- SCは,CO中間物質を早期解体から保護する支架として機能する.
- SCは,クロスオーバー成熟を促進する一時的な,CO特異の区画を生成する可能性があります.
- このメカニズムは,COと非COの場所での修復のタイミングと結果の違いを可能にする可能性があり,精密なメオティック染色体分離を保証します.
関連する概念動画
Recombinant DNA
103.5K
Overview
103.5K
Overview of DNA Repair
33.9K
In order to be passed through generations, genomic DNA must be undamaged and error-free. However, every day, DNA in a cell undergoes several thousand to a million damaging events by natural causes and external factors. Ionizing radiation such as UV rays, free radicals produced during cellular respiration, and hydrolytic damage from metabolic reactions can alter the structure of DNA. Damages caused include single-base alteration, base dimerization, chain breaks, and cross-linkage.
Chemically...
Chemically...
33.9K
Protein Complex Assembly
16.8K
Proteins can form homomeric complexes with another unit of the same protein or heteromeric complexes with different types. Most protein complexes self-assemble spontaneously via ordered pathways, while some proteins need assembly factors that guide their proper assembly. Despite the crowded intracellular environment, proteins usually interact with their correct partners and form functional complexes.
Many viruses self-assemble into a fully functional unit using the infected host cell to...
Many viruses self-assemble into a fully functional unit using the infected host cell to...
16.8K
Protein Complexes with Interchangeable Parts
2.9K
Groups of proteins may form a complex where each protein in this complex has a different role in the overall execution of the complex’s function. Often some of the proteins in the complex can be replaced by a closely related variant to give a complex that contains many of the same components yet is functionally distinct.
The SCF ubiquitin ligase is a protein complex of five individual proteins. This complex attaches ubiquitin to other target proteins to mark them for degradation. In order...
The SCF ubiquitin ligase is a protein complex of five individual proteins. This complex attaches ubiquitin to other target proteins to mark them for degradation. In order...
2.9K
Complex Numbers
322
The real number system cannot represent the square root of a negative number, which restricts solutions for certain equations, such as quadratics with negative discriminants. To address this, the complex number system was developed, introducing the imaginary unit i, where i = √(-1). This extension allows for the representation of all roots, including those involving negative radicands.A complex number is written in the form x + yi, where x and y are real numbers. Here, x represents the...
322
Formation of Complex Ions
26.2K
A type of Lewis acid-base chemistry involves the formation of a complex ion (or a coordination complex) comprising a central atom, typically a transition metal cation, surrounded by ions or molecules called ligands. These ligands can be neutral molecules like H2O or NH3, or ions such as CN− or OH−. Often, the ligands act as Lewis bases, donating a pair of electrons to the central atom. These types of Lewis acid-base reactions are examples of a broad subdiscipline called coordination...
26.2K


