Targeting a key disulfide linkage to regulate RIG-I condensation and cytosolic RNA-sensing PMID: 40229436

ADC Targets in Oncology

2026-04-10

Targeting a key disulfide linkage to regulate RIG-I condensation and cytosolic RNA-sensing

Nat Cell Biol. 2025 May;27(5):817-834. doi: 10.1038/s41556-025-01646-5.

Bin Wang ^# ¹ ² , Yongqiang Wang ^# ³ , Ting Pan ^# ⁴ , Lili Zhou ³ , Yu Ran ¹ ³ , Jing Zou ¹ , Xiaohua Yan ² , Zhenke Wen ³ , Shixian Lin ¹ , Aiming Ren ¹ , Fangwei Wang ¹ , Zhuang Liu ⁵ , Ting Liu ⁶ , Huasong Lu ¹ , Bing Yang ⁷ , Fangfang Zhou ⁸ , Long Zhang ⁹ ¹⁰ ¹¹

Affiliations

1. Department of Radiation Oncology and the State Key Laboratory of Transvascular Implantation Devices, The Second Affiliated Hospital of Zhejiang University School of Medicine, Life Sciences Institute, Zhejiang University, Hangzhou, China.
2. The MOE Basic Research and Innovation Center for the Targeted Therapeutics of Solid Tumors, The First Affiliated Hospital, Jiangxi Medical College Nanchang University, Nanchang, China.
3. Institutes of Biology and Medical Sciences, The First Affiliated Hospital, Suzhou Medical College, Soochow University, Suzhou, China.
4. Shenzhen Key Laboratory of Systems Medicine for Inflammatory Diseases, School of Medicine, Sun Yat-sen University, Shenzhen, China.
5. Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Institute of Functional Nano and Soft Materials (FUNSOM), Soochow University, Suzhou, China.
6. Departments of Cell Biology and General Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Zhejiang University, Hangzhou, China.
7. Department of Radiation Oncology and the State Key Laboratory of Transvascular Implantation Devices, The Second Affiliated Hospital of Zhejiang University School of Medicine, Life Sciences Institute, Zhejiang University, Hangzhou, China. [email protected].
8. Institutes of Biology and Medical Sciences, The First Affiliated Hospital, Suzhou Medical College, Soochow University, Suzhou, China. [email protected].
9. Department of Radiation Oncology and the State Key Laboratory of Transvascular Implantation Devices, The Second Affiliated Hospital of Zhejiang University School of Medicine, Life Sciences Institute, Zhejiang University, Hangzhou, China. [email protected].
10. The MOE Basic Research and Innovation Center for the Targeted Therapeutics of Solid Tumors, The First Affiliated Hospital, Jiangxi Medical College Nanchang University, Nanchang, China. [email protected].
11. Frontiers Medical Center, Tianfu Jincheng Laboratory, Chengdu, China. [email protected].
# Contributed equally.

Abstract

Maintaining innate immune homeostasis is critical for preventing infections and autoimmune diseases but effective interventions are lacking. Here we identified C864-C869-mediated intermolecular disulfide-linkage formation as a critical step for human RIG-I activation that can be bidirectionally regulated to control innate immune homeostasis. The viral-stimulated C864-C869 disulfide linkage mediates conjugation of an SDS-resistant RIG-I oligomer, which prevents RIG-I degradation by E3 ubiquitin-ligase MIB2 and is necessary for RIG-I to perform liquid-liquid phase separation to compartmentalize downstream signalsome, thereby stimulating type I interferon signalling. The corresponding C865S 'knock-in' caused an oligomerization defect and liquid-liquid phase separation in mouse RIG-I, which inhibited innate immunity, resulting in increased viral load and mortality in mice. Using unnatural Amino acids to generate covalent C864-C869 linkage and the development of an interfering peptide to block C864-C869 residues, we bidirectionally regulated RIG-I activities in human diseases. These findings provide in-depth insights on mechanism of RIG-I activation, allowing for the development of methodologies that hold promising implications in clinics.