Flavivirus NS1 possesses NTPase and RNA helix unwinding activities

Ting Shu; Mengyu Hu; Yiyang Li; Mengge Han; Xingyue Wang; Qi Cheng; Xiqiu Xu; Yang Qiu; Xi Zhou

doi:10.1016/j.virs.2026.09.007

October 2026

. doi: 10.1016/j.virs.2026.09.007

Citation: Ting Shu, Mengyu Hu, Yiyang Li, Mengge Han, Xingyue Wang, Qi Cheng, Xiqiu Xu, Yang Qiu, Xi Zhou. Flavivirus NS1 possesses NTPase and RNA helix unwinding activities .VIROLOGICA SINICA, 2026, 41(5) : 1121-1131. http://dx.doi.org/10.1016/j.virs.2026.09.007

黄病毒NS1蛋白具有NTPase活性和RNA解旋活性

舒婷 ^a,b ,
胡梦雨 ^a ,
李依洋 ^a,b ,
韩梦歌 ^a,c ,
王星月 ^a,b ,
程琪 ^d ,
徐希秋 ^a ,
邱洋 ^a,b,, ,
周溪 ^a,b,,

a. 病毒学与生物安全国家重点实验室, 中国科学院武汉病毒研究所, 武汉 430071, 中国;
b. 中国科学院大学, 北京 100049, 中国;
c. 中国科学技术大学, 合肥 230026, 中国;
d. 武汉市金银潭医院, 武汉 430023, 中国

通讯作者： 邱洋, yangqiu@wh.iov.cn; 周溪, zhouxi@wh.iov.cn
收稿日期： 2026-06-18
录用日期： 2026-09-11

摘要

黄病毒是一类节肢动物传播的正链RNA病毒，包括寨卡病毒（ZIKV）、登革病毒2型（DENV2）和流行性乙型脑炎病毒（JEV）等。对于RNA病毒而言，RNA解旋酶通过重塑病毒RNA结构，解开病毒生命周期中产生的双链RNA中间体，在病毒复制中发挥关键作用。本研究发现，来自ZIKV、DENV2和JEV的NS1蛋白均具有NTPase活性和RNA螺旋解旋活性。ZIKV NS1以NTP依赖性方式解旋双链RNA，具有5'→3'方向性，且其解旋活性具有广谱性，能作用于dsRNA、dsDNA和RNA/DNA杂合链。此外，DENV2和JEV的NS1同样具有NTPase和解旋酶活性，但它们在底物偏好性和方向性上存在差异：JEV NS1与ZIKV NS1类似，沿5'→3'方向解旋；而DENV2 NS1仅能解旋较短的双链体，且呈现3'→5'方向性。诱变实验发现，第211位碱性残基（ZIKV中为精氨酸，DENV2/JEV中为赖氨酸）对ZIKV和JEV NS1的解旋活性至关重要，但对DENV2 NS1则非必需。这些发现表明，黄病毒NS1代表了一种此前未被认识的非经典RNA解旋酶，提示NS1可能具备参与RNA重塑过程的能力。
- 黄病毒NS1蛋白
- , NTP酶
- , 解旋酶

Flavivirus NS1 possesses NTPase and RNA helix unwinding activities

Ting Shu ^a,b ,
Mengyu Hu ^a ,
Yiyang Li ^a,b ,
Mengge Han ^a,c ,
Xingyue Wang ^a,b ,
Qi Cheng ^d ,
Xiqiu Xu ^a ,
Yang Qiu ^a,b,, ,
Xi Zhou ^a,b,,

a. State Key Laboratory of Virology and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China;
b. University of Chinese Academy of Sciences, Beijing 100049, China;
c. University of Science and Technology of China, Hefei 230026, China;
d. Wuhan Jinyintan Hospital, Wuhan 430023, China

Corresponding author: Yang Qiu, yangqiu@wh.iov.cn Xi Zhou, zhouxi@wh.iov.cn
Received Date: 18 June 2026
Accepted Date: 11 September 2026

Abstract

Flaviviruses are a group of arthropod-borne positive-sense RNA viruses, including Zika virus (ZIKV), dengue virus 2 (DENV2) and Japanese encephalitis virus (JEV). For RNA viruses, RNA helicases play critical roles in viral replication by unwinding double-stranded RNA intermediates generated in viral life cycles by remodeling viral RNA structures. Here, we report that NS1 proteins from ZIKV, DENV2 and JEV, possesse NTPase and RNA helix unwinding activities. ZIKV NS1 unwinds dsRNA in an NTP-dependent manner with 5′→ 3′ directionality, and its unwinding activity is broad-spectrum, targeting dsRNA, dsDNA and RNA/DNA hybrids. Moreover, both DENV2 and JEV NS1 also display NTPase and helicase activities, but they differ in substrate preference and directionality: JEV NS1 unwinds in the 5′ → 3′ direction like ZIKV NS1, whereas DENV2 NS1 unwinds only shorter duplexes and shows 3′ → 5′ directionality. Mutagenesis identified the basic residue at position 211 (arginine in ZIKV, lysine in DENV2/JEV) as critical for the unwinding activity of ZIKV and JEV NS1, but dispensable for DENV2 NS1. These findings indicate that flavivirus NS1 represents a previously unrecognized non-canonical RNA helicase, suggesting that NS1 may have the capacity to participate in RNA remodeling processes.
- Flavivirus NS1
- , NTPase
- , Helicase

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Electronic Supplementary Material

10.1016j.virs.2026.09.007-ESM.docx