Mcmタンパク質のDNA複製原点への負荷は,Cdc6pとCDKによって制御される
Cell
|August 22, 1997
まとめ
細胞のDNA複製の起源は,開始タンパク質によって調節されます. Cdc6pとMcm7pの結合源はG1で,Mcm7pの結合はCdc6pに依存しており,DNA複製の細胞サイクル制御を示唆しています.
科学分野:
- 細胞生物学 細胞生物学
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
背景:
- DNA複製の起源は,ユカリオットの細胞周期ごとに1回しか発火しない.
- Orc,Cdc6,Mcmsのようなイニシエーションタンパク質は,複製の起源発火の調節に関与しています.
- 細胞サイクル全体を通して原発発火を制御する正確なメカニズムは完全に理解されていません.
研究 の 目的:
- S. cerevisiaeの複製起源とイニシアーションタンパク質の細胞周期依存的関連性を調査する.
- DNA複製の起源活性を調節するCdc6pとMcm7pの役割を解明する.
- DNAの再複製を防ぐ規制メカニズムを特定する.
主な方法:
- フォーマルデヒドのクロスリンクは,タンパク質とDNAの相互作用を in vivo で研究するために使用されました.
- Cdc6pとMcm7pの複製起源との関連性は,異なる細胞サイクルフェーズ (G1,G2,S) で評価されました.
- 子宮外Cdc6p発現がMcm7p募集に及ぼす影響も調査した.
主要な成果:
- Cdc6pとMcm7pは,G1段階の複製起源と特異的に関連しています.
- Mcm7pの起源との関連性は,Cdc6pの存在に依存しています.
- エクトピックCdc6p発現はG2の間に起源関連を許容したが,Mcm7pを勧誘することはなかった.
結論:
- 複製起源の発火は,少なくとも2つの異なるメカニズムによって制御されます.
- 原点でのCdc6p占有は,MCMタンパク質ロードの前提条件である.
- S・M相サイクリン依存キナーゼ (CDK) の活性により,S,G2,M相におけるMcm負荷が防止され,細胞周期毎に一度のDNA複製が保証される.
関連する概念動画
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Two states at the origin of replication
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M cyclin...
Cyclin-dependent kinases, or Cdks, work in concert with cyclins to control cell cycle transitions. M-Cdk, a complex of Cdk1 bound to M cyclin, is a well-known example of this coordinated control that drives the transition from the G2 to the M phase.
M cyclin...
00:50Anaphase Promoting Complex
The stepwise destruction of specific proteins is necessary for the progression and completion of the cell cycle. Such proteins are ubiquitinated by ubiquitin ligases and then subsequently destroyed by the proteasome. The SCF (Skp1/Cullin/F-box) and the anaphase-promoting complex (APC) are two important ubiquitin ligases involved in cell cycle progression. While SCF is active throughout the cell cycle, APC gets activated during metaphase to anaphase transition. Cdc20 or Cdh1 binds to APC and...
02:38S-Cdk Initiates DNA Replication
The cell cycle is a series of events leading to DNA duplication followed by the division of cell content to form two daughter cells. The cell cycle progresses in four stages—the cell increases in size (gap 1 or G1-phase), duplicates its DNA (synthesis or S-phase), prepares to divide (gap 2 or G2-phase), and divides (mitosis or M-phase).
Two states at the origin of replication
In eukaryotes, the initiation of replication occurs at many sites on the chromosomes, called the origins of replication.
Two states at the origin of replication
In eukaryotes, the initiation of replication occurs at many sites on the chromosomes, called the origins of replication.
02:15M-Cdk Drives Transition Into Mitosis
Checkpoints throughout the cell cycle serve as safeguards and gatekeepers, allowing the cell cycle to progress in favorable conditions and slow or halt it in problematic ones. This regulation is known as the cell cycle control system.
Cyclin-dependent kinases, or Cdks, work in concert with cyclins to control cell cycle transitions. M-Cdk, a complex of Cdk1 bound to M cyclin, is a well-known example of this coordinated control that drives the transition from the G2 to the M phase.
M cyclin...
Cyclin-dependent kinases, or Cdks, work in concert with cyclins to control cell cycle transitions. M-Cdk, a complex of Cdk1 bound to M cyclin, is a well-known example of this coordinated control that drives the transition from the G2 to the M phase.
M cyclin...
00:50Anaphase Promoting Complex
The stepwise destruction of specific proteins is necessary for the progression and completion of the cell cycle. Such proteins are ubiquitinated by ubiquitin ligases and then subsequently destroyed by the proteasome. The SCF (Skp1/Cullin/F-box) and the anaphase-promoting complex (APC) are two important ubiquitin ligases involved in cell cycle progression. While SCF is active throughout the cell cycle, APC gets activated during metaphase to anaphase transition. Cdc20 or Cdh1 binds to APC and...