在将基因整合到Aspergillus niger的基因组中,NHEJ和HDR可以同时发生
Susanne Fritsche1,2, Aline Reinfurt1,2, Felix Fronek1,2
1Austrian Centre of Industrial Biotechnology, Muthgasse 18, Vienna, Austria.
Fungal biology and biotechnology
|August 5, 2024
概括
丝状真菌利用非同源端连接 (NHEJ) 和同源导向修复 (HDR) 来进行DNA修复. 这项研究突出了Aspergillus niger中一种新的混合型修复机制,影响了基因工程策略.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 菌类学 菌类学是指菌类学.
背景情况:
- 丝状真菌使用非同源端连接 (NHEJ) 和同源导向修复 (HDR) 来修复DNA双链断裂.
- NHEJ快速修复断裂,但可能导致插入/删除,而HDR使用同类模板提供精确修复.
- 在真菌基因工程中,NHEJ和HDR都是针对性修改的关键工具.
研究的目的:
- 评估基于同质导向修复 (HDR) 的基因整合系统在Aspergillus niger的pyrG位点中的有效性.
- 研究在线状真菌中的基因整合过程中发生的新型DNA修复机制.
主要方法:
- 使用CRISPR-Cas9技术诱导Aspergillus niger pyrG位点中的双链断裂.
- 采用基于同质导向修复 (HDR) 的基因整合系统.
- 通过测序分析变态,以确定DNA修复结果并描述新的修复机制.
主要成果:
- 使用HDR系统实现了91.4%的高基因整合率.
- 发现了一种混合型修复 (MTR) 机制,其中双链断裂同时由NHEJ和HDR修复.
- 在20.3%的转化剂中观察到MTR,在3'端通过NHEJ和5'端通过HDR集成的供体DNA.
结论:
- 评估的基因组整合系统是有效的,用于Aspergillus niger.
- 确定了一种新的混合类型修复 (MTR) 机制,扩大了对线状真菌中DNA修复多样性的理解.
- 这些发现对提高真菌遗传修饰的精度和多样性有重大影响.
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