USP14 negatively regulates IFN signaling by dampening K63-linked ubiquitination of TBK1 in black carp

Can Yang; Juanjuan Shu; Xiao Yang; Yujia Miao; Ji Liu; Jun Li; Jun Xiao; Weiguang Kong; Zhen Xu; Hao Feng

doi:10.1016/j.fsi.2024.109559

USP14 negatively regulates IFN signaling by dampening K63-linked ubiquitination of TBK1 in black carp

Fish Shellfish Immunol. 2024 Apr 16:149:109559. doi: 10.1016/j.fsi.2024.109559. Online ahead of print.

Authors

Can Yang¹, Juanjuan Shu¹, Xiao Yang¹, Yujia Miao¹, Ji Liu¹, Jun Li², Jun Xiao¹, Weiguang Kong³, Zhen Xu³, Hao Feng⁴

Affiliations

¹ State Key Laboratory of Developmental Biology of Freshwater Fish, College of Life Science, Hunan Normal University, Changsha, 410081, China.
² Key Laboratory of Hunan Province for Study and Utilization of Ethnic Medicinal Plant Resources, College of Biological and Food Engineering, Huaihua University, Huaihua, 418008, China.
³ State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China.
⁴ State Key Laboratory of Developmental Biology of Freshwater Fish, College of Life Science, Hunan Normal University, Changsha, 410081, China. Electronic address: fenghao@hunnu.edu.cn.

PMID: 38636737
DOI: 10.1016/j.fsi.2024.109559

Abstract

USP14 regulates the immune related pathways by deubiquitinating the signaling molecules in mammals. In teleost, USP14 is also reported to inhibit the antiviral immune response through TBK1, but its regulatory mechanism remains obscure. To elucidate the role of USP14 in the RLR/IFN antiviral pathway in teleost, the homolog USP14 (bcUSP14) of black carp (Mylopharyngodon piceus) has been cloned and characterize in this paper. bcUSP14 contains 490 amino acids (aa), and the sequence is well conserved among in vertebrates. Over-expression of bcUSP14 in EPC cells attenuated SVCV-induced transcription activity of IFN promoters and enhanced SVCV replication. Knockdown of bcUSP14 in MPK cells led to the increased transcription of IFNs and decreased SVCV replication, suggesting the improved antiviral activity of the host cells. The interaction between bcUSP14 and bcTBK1 was identified by both co-immunoprecipitation and immunofluorescent staining. Co-expressed bcUSP14 obviously inhibited bcTBK1-induced IFN production and antiviral activity in EPC cells. K63-linked polyubiquitination of bcTBK1 was dampened by co-expressed bcUSP14, and bcTBK1-mediated phosphorylation and nuclear translocation of IRF3 were also inhibited by this deubiquitinase. Thus, all the data demonstrated that USP14 interacts with and inhibits TBK1 through deubiquitinating TBK1 in black carp.

Keywords: Black carp; Interferon; TBK1; USP14.