Human coronavirus 3CL protease manipulates host protein STIM1 to facilitate immune evasion

Y Yoon Young Lee (Department of Biological Sciences, College of Information and Biotechnology, Ulsan National Institute of Science and Technology) A Ah Reum Lee (Department of Biomedical Engineering, College of Information and Biotechnology, Ulsan National Institute of Science and Technology) S Seongkyung Seo (Department of Biomedical Engineering, College of Information and Biotechnology, Ulsan National Institute of Science and Technology) U Uni Park (Department of Microbiology and Immunology, College of Medicine, Seoul National University) T Taehun Kim (Department of Microbiology and Immunology, College of Medicine, Seoul National University) S Sang Kwon Lee (Department of Biological Sciences, College of Information and Biotechnology, Ulsan National Institute of Science and Technology) H Hyeongsun Jeong (Department of Biomedical Engineering, College of Information and Biotechnology, Ulsan National Institute of Science and Technology) S Su Ji Jeong (Department of Biomedical Engineering, College of Information and Biotechnology, Ulsan National Institute of Science and Technology) Y Yeong Cheon Kweon (Department of Biomedical Engineering, College of Information and Biotechnology, Ulsan National Institute of Science and Technology) G Go Eun Park (Department of Biological Sciences, College of Information and Biotechnology, Ulsan National Institute of Science and Technology) M Min Ji Kim B Byung-Gyu Kim (Center for Genomic Integrity, Institute for Basic Science, Ulsan National Institute of Science and Technology) T Taejoon Kwon (Department of Biomedical Engineering, College of Information and Biotechnology, Ulsan National Institute of Science and Technology) N Nam-Hyuk Cho (Department of Microbiology and Immunology, College of Medicine, Seoul National University) H Hyug Moo Kwon (Department of Biological Sciences, College of Information and Biotechnology, Ulsan National Institute of Science and Technology) K Kyungjae Myung (Department of Biomedical Engineering, College of Information and Biotechnology, Ulsan National Institute of Science and Technology) S Sang Min Lee (Department of Biological Sciences, College of Information and Biotechnology, Ulsan National Institute of Science and Technology) C Chan Young Park (Department of Biomedical Engineering, College of Information and Biotechnology, Ulsan National Institute of Science and Technology)

Abstract

Coronaviruses rely on intricate interactions with host proteins to create an environment conducive to their replication and survival. The 3CL protease of coronavirus acts as a key mediator, serving a dual role in cleaving viral polyproteins to produce essential components for replication and targeting host proteins to disrupt regulatory pathways and suppress immune defenses. However, the mechanisms by which 3CL protease manipulates host proteins remain poorly understood. Here, we identify STIM1, a substrate of the 3CL protease, as a dual immune suppressor. Cleavage at the Q496 residue generates two stable products, N-terminal (NT) and C-terminal (CT) fragments, which acquire de novo immunomodulatory functions. NT suppresses MAVS aggregation and MAVS-TRAF2-TBK1 signalosome formation, while CT attenuates IKKα-induced p65 phosphorylation and nuclear translocation by interacting with HSP70. Collectively, these dual modules simultaneously lead to the suppression of IFN-β production and the weakening of antiviral defenses. These findings reveal a distinct function of STIM1 and delineate a strategy employed by coronaviruses to modulate host immunity, offering insights into viral pathogenesis and potential avenues for therapeutic intervention.

Article Details

Volume / Issue Vol. 122, Issue 48
Published December 02, 2025
ISSN 0027-8424
Publisher National Academy of Sciences

Authors (18)

Y

Yoon Young Lee

Department of Biological Sciences, College of Information and Biotechnology, Ulsan National Institute of Science and Technology

A

Ah Reum Lee

Department of Biomedical Engineering, College of Information and Biotechnology, Ulsan National Institute of Science and Technology

S

Seongkyung Seo

Department of Biomedical Engineering, College of Information and Biotechnology, Ulsan National Institute of Science and Technology

U

Uni Park

Department of Microbiology and Immunology, College of Medicine, Seoul National University

T

Taehun Kim

Department of Microbiology and Immunology, College of Medicine, Seoul National University

S

Sang Kwon Lee

Department of Biological Sciences, College of Information and Biotechnology, Ulsan National Institute of Science and Technology

H

Hyeongsun Jeong

Department of Biomedical Engineering, College of Information and Biotechnology, Ulsan National Institute of Science and Technology

S

Su Ji Jeong

Department of Biomedical Engineering, College of Information and Biotechnology, Ulsan National Institute of Science and Technology

Y

Yeong Cheon Kweon

Department of Biomedical Engineering, College of Information and Biotechnology, Ulsan National Institute of Science and Technology

G

Go Eun Park

Department of Biological Sciences, College of Information and Biotechnology, Ulsan National Institute of Science and Technology

M

Min Ji Kim

B

Byung-Gyu Kim

Center for Genomic Integrity, Institute for Basic Science, Ulsan National Institute of Science and Technology

T

Taejoon Kwon

Department of Biomedical Engineering, College of Information and Biotechnology, Ulsan National Institute of Science and Technology

N

Nam-Hyuk Cho

Department of Microbiology and Immunology, College of Medicine, Seoul National University

H

Hyug Moo Kwon

Department of Biological Sciences, College of Information and Biotechnology, Ulsan National Institute of Science and Technology

K

Kyungjae Myung

Department of Biomedical Engineering, College of Information and Biotechnology, Ulsan National Institute of Science and Technology

S

Sang Min Lee

Department of Biological Sciences, College of Information and Biotechnology, Ulsan National Institute of Science and Technology

C

Chan Young Park

Department of Biomedical Engineering, College of Information and Biotechnology, Ulsan National Institute of Science and Technology