转子编码核酶使用导向RNA促进它们的自私传播
Chance Meers1, Hoang C Le2,1, Sanjana R Pesari1,3
1Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA.
Nature
|September 27, 2023
概括
插入序列使用RNA引导的DNA裂变通过TnpB和IscB蛋白质,以防止它们在转移过程中丢失. 这种古老的机制对于转体子传播至关重要,
科学领域:
- 微生物学
- 分子生物学
- 遗传学
背景情况:
- 插入序列 (IS) 是编码动员基因的细菌可转移元素.
- IS200/IS605家族使用TnpA转化酶进行"剥离和粘贴"转化.
- 与Cas12和Cas9相关的TnpB和IscB蛋白质具有RNA引导的DNA内核酶活性.
研究的目的:
- 研究TnpB和IscBRNA导向DNA内核酶在IS转移中的生物学作用.
- 确定TnpB和IscB是否可以防止TnpA引起的转子体损失.
- 在CRISPR-Cas系统中探索RNA引导DNA分裂的进化起源.
主要方法:
- 研究了Geobacillus stearothermophilus编码TnpB和IscB的插入序列.
- 评估了TnpA转体酶的活性,以调动转体子.
- 分析了TnpB和IscB核酶对捐赠关节的向.
- 与TnpA和TnpB的联合表达相比,转位子的保留率与单独的TnpA相比较.
主要成果:
- 一个单一的TnpA转移酶在相关的插入序列中表现出广泛的活性.
- 通过RNA引导的TnpB和IscB核酶有效地切割了重新结合的转子子供体关节.
- 与单独使用TnpA相比,TnpB和TnpA的同时表达显著增加了转子留.
- TnpA和TnpB一起增强了重组频率超过单独的TnpB.
结论:
- 通过TnpB和IscB进行RNA引导的DNA裂变对于防止TnpA介导转基因过程中的转基因丢失至关重要.
- 这种活动确保了可转移元素的自私继承和传播.
- 通过RNA引导的DNA分裂代表了原始的生化功能,后来被适应了CRISPR-Cas适应性免疫.
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