小柯机器人

北京大学生命科学学院Chengqi Yi团队近期取得重要工作进展，他们研究提出，近同源tRNA能提高假尿苷介导的过早终止密码子的读取效率和精度。相关研究成果2024年3月6日在线发表于《自然—生物技术》杂志上。

据介绍，可编程RNA假尿苷化已成为一种新型的RNA碱基编辑器，用于抑制可导致截短和无功能蛋白质的过早终止密码子（PTC）。然而，目前校正疾病相关PTC的方法效率低且精度有限。

研究人员开发了RESTART v3工具，它使用近同源tRNA来提高假尿苷修饰的PTC的通读效率。在培养细胞中显示出比RESTART v2平均高约5倍（范围：2.1至9.5倍）的编辑效率，并在囊性纤维化和Hurler综合征的疾病细胞模型中实现了功能性PTC读取。

此外，RESTART v3能够在不影响正常终止密码子的情况下，考虑到有义到无义密码子的自然发生频率，准确掺入近一半PTC位点的原始氨基酸。尽管检测到了脱靶位点，但研究人员没有观察到编码信息或转录物表达水平的变化，总体天然tRNA丰度保持不变。

附：英文原文

Title: Near-cognate tRNAs increase the efficiency and precision of pseudouridine-mediated readthrough of premature termination codons

Author: Luo, Nan, Huang, Qiang, Dong, Liting, Liu, Wenqing, Song, Jinghui, Sun, Hanxiao, Wu, Hao, Gao, Yuan, Yi, Chengqi

Issue&Volume: 2024-03-06

Abstract: Programmable RNA pseudouridylation has emerged as a new type of RNA base editor to suppress premature termination codons (PTCs) that can lead to truncated and nonfunctional proteins. However, current methods to correct disease-associated PTCs suffer from low efficiency and limited precision. Here we develop RESTART v3, which uses near-cognate tRNAs to improve the readthrough efficiency of pseudouridine-modified PTCs. We show an average of ~5-fold (range: 2.1- to 9.5-fold) higher editing efficiency than RESTART v2 in cultured cells and achieve functional PTC readthrough in disease cell models of cystic fibrosis and Hurler syndrome. Furthermore, RESTART v3 enables accurate incorporation of the original amino acid for nearly half of the PTC sites, considering the naturally occurring frequencies of sense-to-nonsense codons, without affecting normal termination codons. Although off-target sites were detected, we did not observe changes to the coding information or the expression level of transcripts, and the overall natural tRNA abundance remained constant.

DOI: 10.1038/s41587-024-02165-8

Source: https://www.nature.com/articles/s41587-024-02165-8

Nature Biotechnology：《自然—生物技术》，创刊于1996年。隶属于施普林格·自然出版集团，最新IF：68.164
官方网址：https://www.nature.com/nbt/
投稿链接：https://mts-nbt.nature.com/cgi-bin/main.plex