USP18 recruits USP20 to promote innate antiviral response through deubiquitinating STING/MITA
Cell Res.
2016 Nov 1. doi: 10.1038/cr.2016.125. [Epub ahead of print]
USP18 recruits USP20 to promote innate antiviral response through deubiquitinating STING/MITA.
Zhang M
1,
Zhang MX
1,
Zhang Q
1,
Zhu GF
1,
Yuan L
1,
Zhang DE
2,
Zhu Q
3,
Yao J
1,
Shu HB
4,
Zhong B
1,4.
- 1State Key Laboratory of Virology, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, China.
- 2Department of Pathology and Division of Biological Sciences, Moores UCSD Cancer Center, University of California San Diego, La Jolla, California 92093, USA.
- 3State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, China.
- 4Medical Research Institute, School of Medicine, Wuhan University, Wuhan 430071, China.
Abstract
STING (also known as MITA) mediates the innate antiviral signaling and ubiquitination of STING is key to its function. However, the deubiquitination process of STING is unclear. Here we report that USP18 recruits USP20 to deconjugate K48-linked ubiquitination chains from STING and promotes the stability of STING and the expression of type I IFNs and proinflammatory cytokines after DNA virus infection. USP18 deficiency or knockdown of USP20 resulted in enhanced K48-linked ubiquitination and accelerated degradation of STING, and impaired activation of IRF3 and NF-κB as well as induction of downstream genes after infection with DNA virus HSV-1 or transfection of various DNA ligands. In addition, Usp18-/- mice were more susceptible to HSV-1 infection compared with the wild-type littermates. USP18 did not deubiquitinate STING in vitro but facilitated USP20 to catalyze deubiquitination of STING in a manner independent of the enzymatic activity of USP18. In addition, reconstitution of STING into Usp18-/- MEFs restored HSV-1-induced expression of downstream genes and cellular antiviral responses. Our findings thus uncover previously uncharacterized roles ofUSP18 and USP20 in mediating virus-triggered signaling and contribute to the understanding of the complicated regulatory system of the innate antiviral responses.Cell Research advance online publication 1 November 2016; doi:10.1038/cr.2016.125.
