STING single amino acid polymorphisms modulate iridovirus immune evasion and pathogenicity spectrum

X Xiaowei Qin (State Key Laboratory for Biocontrol & Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Guangdong Province Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-sen University) M Mincong Liang (School of Life Sciences, China-Association of Southeast Asian Nations (ASEAN) Belt and Road Joint Laboratory on Mariculture Technology and State Key Laboratory for Biocontrol, Guangdong Province Key Laboratory for Aquatic Economic Animals, Sun Yat-sen University) W Weiqiang Pan (School of Life Sciences, China-Association of Southeast Asian Nations (ASEAN) Belt and Road Joint Laboratory on Mariculture Technology and State Key Laboratory for Biocontrol, Guangdong Province Key Laboratory for Aquatic Economic Animals, Sun Yat-sen University) Z Zhipeng Zhan (School of Life Sciences, China-Association of Southeast Asian Nations (ASEAN) Belt and Road Joint Laboratory on Mariculture Technology and State Key Laboratory for Biocontrol, Guangdong Province Key Laboratory for Aquatic Economic Animals, Sun Yat-sen University) C Chuanrui Li (State Key Laboratory for Biocontrol & Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Guangdong Province Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-sen University) Y Yanlin You (State Key Laboratory for Biocontrol & Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Guangdong Province Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-sen University) S Shaoping Weng (School of Life Sciences, China-Association of Southeast Asian Nations (ASEAN) Belt and Road Joint Laboratory on Mariculture Technology and State Key Laboratory for Biocontrol, Guangdong Province Key Laboratory for Aquatic Economic Animals, Sun Yat-sen University) J Jianguo He (School of Life Sciences, China-Association of Southeast Asian Nations (ASEAN) Belt and Road Joint Laboratory on Mariculture Technology and State Key Laboratory for Biocontrol, Guangdong Province Key Laboratory for Aquatic Economic Animals, Sun Yat-sen University) C Changjun Guo (School of Life Sciences, China-Association of Southeast Asian Nations (ASEAN) Belt and Road Joint Laboratory on Mariculture Technology and State Key Laboratory for Biocontrol, Guangdong Province Key Laboratory for Aquatic Economic Animals, Sun Yat-sen University)

Abstract

The evolutionary arms race between viruses and hosts shapes host antiviral defenses and viral immune evasion, yet the mechanisms driving divergence in viral cross-species pathogenicity remain unclear. Here, we investigated the role of single amino acid polymorphisms (SAPs) in stimulator of interferon genes (STING) in modulating immune evasion and pathogenicity spectrum of infectious spleen and kidney necrosis virus (ISKNV). The ISKNV-encoded protein VP012R targets mandarin fish STING ( sc STING) for ubiquitination at residues C196 and K315, promoting its degradation to suppress interferon responses. Importantly, the K315/R315 polymorphism acts as a molecular switch: Susceptible species with the K315 residue exhibit STING degradation and viral immune evasion, whereas resistant species with the R315 residue maintain STING stability and antiviral defenses. Phylogenetic analysis linked K315 to high-mortality hosts (≥50% lethality) vs. R315 in resistant species (≤25% lethality). These findings suggest that the molecular mechanisms underlying the viral pathogenicity spectrum may be modulated by host protein SAPs, thereby enhancing our understanding of host–virus coevolution in terms of biological diversity.

Article Details

Volume / Issue Vol. 123, Issue 4
Published January 27, 2026
ISSN 0027-8424
Publisher National Academy of Sciences

Authors (9)

X

Xiaowei Qin

State Key Laboratory for Biocontrol & Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Guangdong Province Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-sen University

M

Mincong Liang

School of Life Sciences, China-Association of Southeast Asian Nations (ASEAN) Belt and Road Joint Laboratory on Mariculture Technology and State Key Laboratory for Biocontrol, Guangdong Province Key Laboratory for Aquatic Economic Animals, Sun Yat-sen University

W

Weiqiang Pan

School of Life Sciences, China-Association of Southeast Asian Nations (ASEAN) Belt and Road Joint Laboratory on Mariculture Technology and State Key Laboratory for Biocontrol, Guangdong Province Key Laboratory for Aquatic Economic Animals, Sun Yat-sen University

Z

Zhipeng Zhan

School of Life Sciences, China-Association of Southeast Asian Nations (ASEAN) Belt and Road Joint Laboratory on Mariculture Technology and State Key Laboratory for Biocontrol, Guangdong Province Key Laboratory for Aquatic Economic Animals, Sun Yat-sen University

C

Chuanrui Li

State Key Laboratory for Biocontrol & Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Guangdong Province Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-sen University

Y

Yanlin You

State Key Laboratory for Biocontrol & Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Guangdong Province Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-sen University

S

Shaoping Weng

School of Life Sciences, China-Association of Southeast Asian Nations (ASEAN) Belt and Road Joint Laboratory on Mariculture Technology and State Key Laboratory for Biocontrol, Guangdong Province Key Laboratory for Aquatic Economic Animals, Sun Yat-sen University

J

Jianguo He

School of Life Sciences, China-Association of Southeast Asian Nations (ASEAN) Belt and Road Joint Laboratory on Mariculture Technology and State Key Laboratory for Biocontrol, Guangdong Province Key Laboratory for Aquatic Economic Animals, Sun Yat-sen University

C

Changjun Guo

School of Life Sciences, China-Association of Southeast Asian Nations (ASEAN) Belt and Road Joint Laboratory on Mariculture Technology and State Key Laboratory for Biocontrol, Guangdong Province Key Laboratory for Aquatic Economic Animals, Sun Yat-sen University