在兰巴结合性重组过程中,附着部位的突触包括通过蛋白质-DNA复合体捕获裸体DNA
E Richet1, P Abcarian, H A Nash
1Laboratory of Molecular Biology National Institute of Mental Health Bethesda, Maryland 20892.
Cell
|January 15, 1988
概括
细菌附着部位 (attB) 通过与病毒内体的碰撞获得Int复合酶,而不是直接结合. 在兰巴达集成过程中这种DNA捕获是蛋白质驱动的,而不是取决于同质性.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 病毒学 病毒学
背景情况:
- 菌体的lambda集成需要Int重组酶来结合和分裂病毒 (attP) 和宿主 (attB) DNA附着部位.
- 通过attB DNA获得Int重组酶进行整合的确切机制尚不清楚.
研究的目的:
- 阐明在兰巴集成过程中attB位点对Int重组酶的获取机制.
- 研究DNA同质性和蛋白质-DNA相互作用在attB-attP突触中的作用.
主要方法:
- 用DNA足迹测试来评估Int-DNA结合.
- 一种新型的DNA裂变试验,用于监测重组动态.
- 在有竞争DNA的情况下分析attB-attP相互作用.
主要成果:
- 细菌的attB部位在有竞争DNA的情况下无法稳定地结合Int复合酶.
- attB通过与intasome的碰撞获得Int重组酶,intasome是在attP位点上形成的复合体.
- 通过attP intasome捕获attB独立于DNA同质性,由蛋白质相互作用驱动.
结论:
- 兰巴达集成涉及一种新的机制,即attB通过蛋白质介导相互作用被attP intasome捕获.
- attB和attP之间的突触是由蛋白质-DNA和蛋白质-蛋白质相互作用控制的,而不是DNA序列同质.
- 这一发现澄清了特定地点重组和核蛋白组合形成的动态.
相关概念视频
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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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