通过远距离的Reb1蛋白介导作用调节复制终止
Samarendra K Singh1, Sarah Sabatinos, Susan Forsburg
1Department of Molecular Biology and Biochemistry, Medical University of South Carolina, Charleston, SC 29425, USA.
Cell
|September 21, 2010
概括
蛋白质相互作用调节DNA复制的终止. Reb1蛋白调解终结 (Ter) 位点之间的相互作用,影响Schizosaccharomyces pombe的DNA分叉逮捕和基因表达.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 生物化学 生物化学
背景情况:
- 由蛋白质介导的长距离DNA相互作用影响基因表达.
- 特定位点的复制终止对于基因组的稳定性至关重要.
研究的目的:
- 为了研究终结 (Ter) 位点之间的蛋白质介导相互作用在调节Schizosaccharomyces pombe的DNA复制终结中的作用.
- 阐明Reb1蛋白通过跨和内染色体相互作用控制复制终止的机制.
主要方法:
- 在Schizosaccharomyces pombe.中进行特定地点的复制终止测试.
- 在体外DNA循环测试.
- 在体内进行分叉拦截分析.
- 对Ter位点和Reb1蛋白的突变分析.
主要成果:
- Reb1蛋白催化复制终止,并调解Ter位点之间的相互作用.
- 在cis作用的反平行Ter位点之间的Reb1依赖相互作用在体外诱导DNA循环,并在体内增强分叉停止.
- 观察到不同染色体上的Ter位之间相互作用 (染色体亲吻),染色体2上的Ter位与染色体1上的Ter位相互作用.
- 染色体1上一个关键的Ter位点的失活,减少了染色体2 Ter位点的分叉停止.
结论:
- 同一个染色体内和不同染色体之间的Ter位点之间的蛋白质介导相互作用在调节DNA复制终结方面发挥着重要作用.
- Reb1蛋白是这些相互作用的关键调解者,通过合作机制影响分叉捕获.
- 这些发现揭示了通过长距离染色体相互作用介导的对DNA复制终止的新型控制层.
相关概念视频
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03:01The Replisome
DNA replication is carried out by a large complex of proteins that act in a coordinated matter to achieve high-fidelity DNA replication. Together this complex is known as the DNA replication machinery or the replisome.
The synthesis of the leading and lagging strands is a highly coordinated process. To explain this, the “Trombone model” was proposed by Bruce Alberts in 1980. The DNA loop formation starts when a primer is synthesized on the parent lagging strand. The loop grows with the...
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