通过PAM灵活的基因组编辑,使用工程化Cas9进行编辑
Lin Zhao1, Sabrina R T Koseki1, Rachel A Silverstein2,3,4
1Department of Biomedical Engineering, Duke University, Durham, NC, USA.
Nature communications
|October 4, 2023
概括
研究人员通过结合SpRY和Sc+Cas9变体,设计出一种新的CRISPR酶Spryc. 这种嵌合体酶表现出高度灵活的原空间体相邻动机 (PAM) 识别,使得精确的基因组编辑跨多种序列的潜在治疗用途.
科学领域:
- 生物化学 生化学
- 分子生物学分子生物学
- 基因编辑技术的技术
背景情况:
- 克里斯普尔酶需要一个特定的原空间器相邻动机 (PAM) 来识别目标部位.
- 这一PAM要求限制了基因组编辑应用程序对某些DNA序列的可访问性.
- 现有的Cas9变种在PAM灵活性,效率或准确性方面存在局限性.
研究的目的:
- 为了设计一种具有增强和灵活的原空间器相邻动机 (PAM) 识别的仿真CRISPR酶.
- 克服传统CRISPR-Cas9系统对序列可访问性的限制.
- 开发一种多功能基因组编辑工具,用于各种治疗应用.
主要方法:
- 重组SpRY的PAM交互域 (NRN>NYN PAM偏好) 与Sc++的N端 (NNG编辑功能).
- 产生一种被指定为SpRYc的仿真酶,整合了两种母Cas9变体的特性.
- 展示了SpRYc编辑多种PAM和与疾病相关的遗传位点的能力.
主要成果:
- 仿真SpRYc酶表现出高度灵活和广泛的PAM识别能力.
- SpRYc成功地和具体地编辑了各种原始空间器相邻图案 (PAM).
- 该酶表明编辑与疾病相关的位置,表明潜在的治疗相关性.
结论:
- 整合性蛋白质设计是设计先进的Cas9变体的强大策略.
- 在PAM识别方面,SpRYc提供了强大的灵活性,扩大了CRISPR基因组编辑的范围.
- 开发的酶激励下游应用程序,需要精确的基因组定位和编辑以前无法访问的网站.
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