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一种具有对小非编码RNA的内核酶活性的非自然酶
Noreen Ahmed1, Nadine Ahmed1, Didier A Bilodeau1
1Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Ontario, K1N 6N5, Canada.
Nature communications
|June 24, 2023
概括
研究人员使用遗传密码扩展设计了一种非自然的内核酶酶. 这种新型酶专门分裂短干扰RNAs (siRNA) 和microRNAs (miRNAs),显示了针对肝炎C病毒 (HCV) 等疾病的治疗应用的潜力.
科学领域:
- 生物化学 生化学
- 分子生物学分子生物学
- 合成生物学 合成生物学
背景情况:
- 内核酶是DNA/RNA处理的重要酶.
- 现有的内核酶不会向像siRNA和miRNA这样的非编码RNA.
- 遗传密码扩展为设计非自然酶功能提供了一条新的途径.
研究的目的:
- 创建一种新的非自然内核酶,能够分裂非编码RNA.
- 研究工程酶的催化活性和特异性.
- 在疾病模型中评估非自然内核酶的治疗潜力.
主要方法:
- 基因代码扩展被用来将一种金属化非自然氨基酸 (BpyAla) 引入蛋白质支架 (p19).
- 工程蛋白 (p19-T111BpyAla) 被铜激活,形成一种非自然的内核酶.
- 通过光测定,人类细胞的全球miRNA分析和评估与C型肝炎病毒 (HCV) 相关的miRNA水平,证实了酶活性.
主要成果:
- 经过工程设计的p19-T111BpyAla证明了短干扰RNA (siRNA) 和人类微RNA (miRNA) 的催化位点特异性分裂.
- 全球miRNA分析证实了该酶在人类细胞系内分裂内源性miRNA的能力.
- 针对miR-122,这是肝炎C病毒 (HCV) 复制的关键因素,显示miR-122水平的耗尽,反映了现有的对抗药物的治疗效果.
结论:
- 遗传密码的扩展成功地产生了一种功能性的非自然内核酶,向非编码RNA.
- 工程酶对siRNA和miRNA具有特异性,具有治疗干预的潜力.
- 这项工作为设计RNA向酶建立了一个新的平台,在治疗像HCV这样的病毒感染方面具有潜在的应用.
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