関連する実験動画
Updated: May 11, 2026

07:27
Direct Restart of a Replication Fork Stalled by a Head-On RNA Polymerase
Published on: April 30, 2010
まとめ
R6Kプラズミドの複製終端は,in vivoプロセスと同様に,DNA複製フォークをin vitroで停止します. この終結は,膜結合やプラズミドでコードされた因子を必要とせず,宿主染色体の関与を示唆します.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
- 微生物学 微生物学とは
背景:
- R6K薬剤耐性因子の複製末端は,DNA複製末端において重要な役割を果たしています.
- 複製終了メカニズムを理解することは,ゲノム安定性と耐薬性を理解するために不可欠です.
- pBR313 と pBR322 のようなプラズミドベクトルは,細菌のDNA要素のクローン化と研究に一般的に使用されます.
研究 の 目的:
- R6K複製末端のインビトロ活性を調査する.
- 端末に特定の細胞構成要素または機能の条件が必要かどうかを判断する.
- R6K端末によって媒介される複製フォークアストのメカニズムを解明する.
主な方法:
- R6K複製端末をpBR313とpBR322のプラズミッドベクトルにクローンする.
- Escherichia coliの細胞抽出物を用いてin vitro DNA複製アッセイを行う.
- 端末配列に対する複製フォークアストの位置を分析する.
主要な成果:
- クローンされたR6K複製末端は,単向複製フォークをin vitroで成功裏に停止しました.
- 端末の位置が原点に対して変化したとき,捕獲部位は相応に移動した.
- 複製の終結は,E. coliの抽出物には,定住の終端を含むプラズミドが含まれているかどうかにかかわらず,in vitroで発生しました.
結論:
- In vitro複製の終了は,in vivoプロセスに密接に模倣しています.
- R6K複製末端の活性には,膜結合は必須ではない.
- 端末配列自体はトランザクションファクターをコードしませんが,そのようなファクターは宿主染色体によってコードされる可能性があります.
関連する概念動画
Replication in Prokaryotes
Overview
Replication in Prokaryotes
Overview
The DNA Replication Fork
An organism’s genome needs to be duplicated in an efficient and error-free manner for its growth and survival. The replication fork is a Y-shaped active region where two strands of DNA are separated and replicated continuously. The coupling of DNA unzipping and complementary strand synthesis is a characteristic feature of a replication fork. Organisms with small circular DNA, such as E. coli, often have a single origin of replication; therefore, they have only two replication forks, one in...
Homologous Recombination
The basic reaction of homologous recombination (HR) involves two chromatids that contain DNA sequences sharing a significant stretch of identity. One of these sequences uses a strand from another as a template to synthesize DNA in an enzyme-catalyzed reaction. The final product is a novel amalgamation of the two substrates. To ensure an accurate recombination of sequences, HR is restricted to the S and G2 phases of the cell cycle. At these stages, the DNA has been replicated already and the...
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...
Replication in Prokaryotes
DNA replication has three main steps: initiation, elongation, and termination. Replication in prokaryotes begins when initiator proteins bind to the single origin of replication (ori) on the cell's circular chromosome. Replication then proceeds around the entire circle of the chromosome in each direction from the two replication forks, resulting in two DNA molecules.
Many Proteins Work Together to Replicate the Chromosome
Replication is coordinated and carried out by a host of specialized...
Many Proteins Work Together to Replicate the Chromosome
Replication is coordinated and carried out by a host of specialized...

