13SコンデンシンによるDNAのATP依存の陽性スーパーコイル化:染色体凝縮の生化学的含意
Cell
|August 22, 1997
まとめ
13Sコンデンシン (染色体凝縮に不可欠なタンパク質複合体) は,DNA刺激によるATPase活性を示しています. ATPの水解を用いてDNAを包み込み,ミトーシス中のクロマチンの凝縮を潜在的に説明する.
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
- バイオケミストリー バイオケミストリー
背景:
- ミトスの染色体凝縮は,正確な細胞分裂に不可欠です.
- SMCタンパク質を含む13Sコンデンシン複合体は,このプロセスに関与しています.
- コンデンシンメカニズムを理解することは,細胞サイクル調節の鍵です.
研究 の 目的:
- 13Sコンデンシンの生化学的活性を調べるために.
- コンデンシン機能におけるATP水解の役割を明らかにする.
- コンデンシンとDNA構造の相互作用を調査する.
主な方法:
- ATPaseの活性を測定する生化学的測定法.
- 構造化DNAを用いたDNA結合研究.
- 閉じた円形のDNAとトポイソメラーゼIを用いたスーパーコーリングアッセイ.
主要な成果:
- 13SコンデンシンにはDNA刺激によるATPase活性がある.
- 複合体は,十字架形DNAのような構造化DNAに優先的に結合する.
- コンデンシンは,ATPに依存した方法でDNAに陽性スーパーコイルを導入します.
結論:
- 13SコンデンシンはATPの水解によりDNAを包み込む.
- このDNAの包装メカニズムは,ミトーシス中のクロマチンの凝縮に寄与する可能性がある.
- この発見は,染色体凝縮の分子基礎についての洞察を提供します.
関連する概念動画
02:21Chromatin Packaging
Each human somatic cell contains 6 billion base-pairs of DNA. Each base-pair is 0.34 nm long, which means that each diploid cell contains a staggering 2 meters of DNA. How is such a long DNA strand packed inside a nucleus measuring only 10 - 20 microns in diameter?
The chromatin
In combination with specialized DNA binding protein called Histones, the DNA double helix forms a compact DNA: protein complex called chromatin. The chromatin itself is further compacted into higher-order structures.
The chromatin
In combination with specialized DNA binding protein called Histones, the DNA double helix forms a compact DNA: protein complex called chromatin. The chromatin itself is further compacted into higher-order structures.
02:02DNA Topoisomerases
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Types and Mechanism of action
Topoisomerases are divided into two main types. Type I...
Types and Mechanism of action
Topoisomerases are divided into two main types. Type I...
02:15Condensins
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The plant and animal cells contain two types of condensin complexes—condensin I and condensin II. Both complexes have five subunits: two SMC (Structural Maintenance of Chromosomes) subunits, a kleisin subunit, and two HEAT-repeat...
The plant and animal cells contain two types of condensin complexes—condensin I and condensin II. Both complexes have five subunits: two SMC (Structural Maintenance of Chromosomes) subunits, a kleisin subunit, and two HEAT-repeat...
02:11Forces Acting on Chromosomes
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Microtubules and motor proteins exert two types of forces on...
Microtubules and motor proteins exert two types of forces on...
02:15Condensins
Condensins are large protein complexes that use ATP to fuel the assembly of chromosomes during mitosis. They transform the tangled, shapeless mass of post-interphase DNA into individualized chromosomes by compacting, organizing, and segregating chromosomal DNA.
The plant and animal cells contain two types of condensin complexes—condensin I and condensin II. Both complexes have five subunits: two SMC (Structural Maintenance of Chromosomes) subunits, a kleisin subunit, and two HEAT-repeat...
The plant and animal cells contain two types of condensin complexes—condensin I and condensin II. Both complexes have five subunits: two SMC (Structural Maintenance of Chromosomes) subunits, a kleisin subunit, and two HEAT-repeat...
01:32Chromatin Packaging
Each human somatic cell contains 6 billion base pairs of DNA. Each base pair is 0.34 nm long, meaning each diploid cell contains a staggering 2 meters of DNA. This long DNA strand is packed inside a nucleus measuring only 10-20 microns in diameter with the help of specialized DNA-binding proteins called histones. Together they form a compact DNA-protein complex called chromatin. The chromatin is further compacted into higher-order structures. The highest level of compaction is achieved during...