PDF(Pubmed)
Abstract：
RNA base editors should ideally be free of immunogenicity, compact, efficient, and specific, which has not been achieved for C > U editing. Here we first describe a compact C > U editor entirely of human origin, created by fusing the human C > U editing enzyme RESCUE-S to Cas inspired RNA targeting system (CIRTS), a tiny, human-originated programmable RNA-binding domain. This editor, CIRTS-RESCUEv1 (V1), was inefficient. Remarkably, a short histidine-rich domain (HRD), which is derived from the internal disordered region (IDR) in the human CYCT1, a protein capable of liquid-liquid phase separation (LLPS), enhanced V1 editing at on-targets as well as off-targets, the latter effect being minor. The V1-HRD fusion protein formed puncta characteristic of LLPS, and various other IDRs (but not an LLPS-impaired mutant) could replace HRD to effectively induce puncta and potentiate V1, suggesting that the diverse domains acted via a common, LLPS-based mechanism. Importantly, the HRD fusion strategy was applicable to various other types of C > U RNA editors. Our study expands the RNA editing toolbox and showcases a general method for stimulating C > U RNA base editors.
摘要：
理想情况下，RNA碱基编辑器应该没有免疫原性，紧凑型,高效,具体,这在C>U编辑中还没有实现。在这里，我们首先描述一个完全来自人类的紧凑型C>U编辑器，通过将人类C>U编辑酶RESCUE-S与Cas启发的RNA靶向系统（CIRTS）融合而创建，一个微小的，人类起源的可编程RNA结合域。这个编辑,CIRTS-RESCUEv1(V1),效率低下。值得注意的是,短的富含组氨酸的结构域（HRD），它来自人类CYCT1的内部无序区（IDR），一种能够进行液-液相分离（LLPS）的蛋白质，增强了在目标和非目标的V1编辑，后一种影响很小。V1-HRD融合蛋白形成LLPS特征的斑点，和各种其他IDR（但不是LLPS受损的突变体）可以替代HRD以有效诱导puncta并增强V1，这表明不同的结构域通过一个共同的，基于LLPS的机制。重要的是,HRD融合策略适用于各种其他类型的C>URNA编辑。我们的研究扩展了RNA编辑工具箱，并展示了刺激C>URNA碱基编辑器的一般方法。
