関連する実験動画
Updated: May 16, 2026

07:27
Direct Restart of a Replication Fork Stalled by a Head-On RNA Polymerase
Published on: April 29, 2010
再結合で再起動された複製は,逆転の繰り返しで逆転の染色体融合を起こします
Ken'Ichi Mizuno1, Izumi Miyabe, Stephanie A Schalbetter
1Genome Damage and Stability Centre, University of Sussex, Brighton, East Sussex BN1 9RQ, UK.
Nature
|November 27, 2012
まとめ
DNA損傷後の複製再起動は,染色体の再編成を引き起こす可能性があります. 再起動されたフォークは,反転した繰り返しでUターンし,癌やゲノム疾患に関与する総染色体再編成 (GCRs) とコピー数変異 (CNVs) を発生させます.
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
- がん研究 がん研究
背景:
- DNA複製の障害は,総染色体再配置 (GCRs) と複製数変異 (CNVs) を引き起こします.
- 環境要因と腫瘍遺伝子の誘発による増殖によって引き起こされる複製ストレスが,ガンにおけるGCRとCNVを促進する.
- GCRsとCNVsは,ヒトゲノム障害とがん発症に関連しており,治療抵抗性につながる可能性がある.
研究 の 目的:
- 複製の再始動が同種の再結合によってもたらす結果を調査する.
- 分裂酵母における染色体再構成の新たなメカニズムを特定する.
主な方法:
- 分裂酵母における複製再起動メカニズムを研究した.
- ホモログな再結合駆動再起動後の小さな反転の繰り返しでフォークの行動が観察されました.
主要な成果:
- リコンビネーションで再起動されたフォークが,小さな反転繰り返しでUターンする染色体再配置の新しいメカニズムを特定しました.
- このUターンイベントは,最大40分の1の複製イベントで観察されました.
結論:
- リコンビネーション駆動の複製再起動は,反転繰り返しのUターンイベントに高い傾向があります.
- この誤りやすい再起動メカニズムは,ガンにおけるGCRと遺伝子増幅に寄与する.
- また,ヒトゲノム疾患における非再発性CNVにも寄与する.
関連する概念動画
Conservative Site-specific Recombination and Phase Variation
Because the DNA segments are cut and reorganized in a direction-specific manner, site-specific recombination has emerged as an efficient genetic engineering technique. Flippase and Cyclization recombinases or Flp and Cre, respectively, are two members of the tyrosine recombinase family derived from bacteriophages, that are used to mediate site-specific DNA insertions, deletions, and targeted expression of proteins in mammalian cell lines.
The recognition sites for Cre recombinase called LoxP...
The recognition sites for Cre recombinase called LoxP...
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...
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...
Viral Recombination
Cells are sometimes infected by more than one virus at once. When two viruses disassemble to expose their genomes for replication in the same cell, similar regions of their genomes can pair together and exchange sequences in a process called recombination. Alternatively, viruses with segmented genomes can swap segments in a process called reassortment.
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...

