英国弗朗西斯·克里克研究所Caetano Reis e Sousa、Enzo Z. Poirier等研究人员合作发现，Dicer的一种亚型保护哺乳动物干细胞免受多种RNA病毒的侵害。相关论文于2021年7月9日发表在《科学》杂志上。

研究人员鉴定了一种Dicer异构体，称为抗病毒Dicer（aviD），它通过切割病毒双链RNA来协调抗病毒RNA干扰（RNAi），从而保护组织干细胞免受RNA病毒（包括寨卡病毒和严重急性呼吸系统综合症冠状病毒2，SARS-CoV-2）的侵害。这项工作阐明了哺乳动物先天免疫中抗病毒RNAi的分子调控，其可根据细胞的分化状态定制不同的细胞内在抗病毒途径。

据悉，在哺乳动物中，对病毒的早期抵抗依赖于干扰素，这可以保护分化细胞而不是干细胞免受病毒复制。许多其他生物依赖于由切割病毒双链RNA的特化Dicer蛋白介导的RNAi。RNAi是否也有助于哺乳动物抗病毒免疫仍然存在争议。

附：英文原文

Title: An isoform of Dicer protects mammalian stem cells against multiple RNA viruses

Author: Enzo Z. Poirier, Michael D. Buck, Probir Chakravarty, Joana Carvalho, Bruno Frederico, Ana Cardoso, Lyn Healy, Rachel Ulferts, Rupert Beale, Caetano Reis e Sousa

Issue&Volume: 2021/07/09

Abstract: In mammals, early resistance to viruses relies on interferons, which protect differentiated cells but not stem cells from viral replication. Many other organisms rely instead on RNA interference (RNAi) mediated by a specialized Dicer protein that cleaves viral double-stranded RNA. Whether RNAi also contributes to mammalian antiviral immunity remains controversial. We identified an isoform of Dicer, named antiviral Dicer (aviD), that protects tissue stem cells from RNA viruses—including Zika virus and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)—by dicing viral double-stranded RNA to orchestrate antiviral RNAi. Our work sheds light on the molecular regulation of antiviral RNAi in mammalian innate immunity, in which different cell-intrinsic antiviral pathways can be tailored to the differentiation status of cells.

DOI: 10.1126/science.abg2264

Source: https://science.sciencemag.org/content/373/6551/231