関連する実験動画
Updated: Jun 13, 2026

07:27
Direct Restart of a Replication Fork Stalled by a Head-On RNA Polymerase
Published on: April 29, 2010
転写因子DksAは,DNA複製と転写機構の間の衝突を防止する
Ashley K Tehranchi1, Matthew D Blankschien, Yan Zhang
1Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA.
Cell
|May 19, 2010
まとめ
栄養素反応性トランスクリプション因子DksAは,トランスクリプションの障害を取り除き,飢餓中のDNA複製の障害を防ぐ. これにより,複製フォークの進行とDNAの完全性が,その開始活動とは独立して確保されます.
科学分野:
- 分子生物学は分子生物学である.
- 微生物学 微生物学とは
- 遺伝学 遺伝学とは
背景:
- 細胞のDNA複製は,栄養素の可用性の変動にもかかわらず,正確であり続けなければなりません.
- 栄養ストレス下での複製障害を防ぐ要因は,完全に理解されていません.
研究 の 目的:
- 栄養素の不足中にDNA複製の忠実さを維持するDksAの役割を調査する.
- DksAが複製停止を防ぐメカニズムを解明する.
主な方法:
- DksAがないEscherichia coliの変異体を使用した.
- アミノ酸飢餓条件下で複製停止を研究した.
- 転写とRNAポリメラーゼの活性が複製に与える影響を分析した.
主要な成果:
- DksAの欠如は,アミノ酸の飢餓中に急速な複製停止を引き起こし,アクティブな転写を必要とします.
- 複製停止はRNAポリメラーゼ変異体によって緩和され,外因的なDNA損傷とは独立しています.
- DksAの役割は,開始ではなく,転写の延長活動を含み,GreA/B因子によってサポートされています.
結論:
- DksAを含む転写延長因子は,複製と転写の間の衝突を解決するために不可欠です.
- これらの要因は,複製フォークの進行を保護し,栄養ストレス下でのDNAの完全性を維持します.
関連する概念動画
S-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.
S-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.
Restarting Stalled Replication Forks
DNA replication is initiated at sites containing predefined DNA sequences known as origins of replication. DNA is unwound at these sites by the minichromosome maintenance (MCM) helicase and other factors such as Cdc45 and the associated GINS complex.The unwound single strands are protected by replication protein A (RPA) until DNA polymerase starts synthesizing DNA at the 5’ end of the strand in the same direction as the replication fork. To prevent the replication fork from falling apart, a...
Restarting Stalled Replication Forks
DNA replication is initiated at sites containing predefined DNA sequences known as origins of replication. DNA is unwound at these sites by the minichromosome maintenance (MCM) helicase and other factors such as Cdc45 and the associated GINS complex.The unwound single strands are protected by replication protein A (RPA) until DNA polymerase starts synthesizing DNA at the 5’ end of the strand in the same direction as the replication fork. To prevent the replication fork from falling apart, a...
DNA Damage can Stall the Cell Cycle
In response to DNA damage, cells can pause the cell cycle to assess and repair the breaks. However, the cell must check the DNA at certain critical stages during the cell cycle. If the cell cycle pauses before DNA replication, the cells will contain twice the amount of DNA. On the other hand, if cells arrest after DNA replication but before mitosis, they will contain four times the normal amount of DNA. With a host of specialized proteins at their disposal,cells must use the right protein at...
DNA Damage Can Stall the Cell Cycle
In response to DNA damage, cells can pause the cell cycle to assess and repair the breaks. However, the cell must check the DNA at certain critical stages during the cell cycle. If the cell cycle pauses before DNA replication, the cells will contain twice the amount of DNA. On the other hand, if cells arrest after DNA replication but before mitosis, they will contain four times the normal amount of DNA. With a host of specialized proteins at their disposal,cells must use the right protein at...
