tetano
Editor, Senior Moderator
J Virol
. 2022 Apr 7;e0003722.
doi: 10.1128/jvi.00037-22. Online ahead of print.
SARS-CoV-2 nsp5 Exhibits Stronger Catalytic Activity and Interferon Antagonism than Its SARS-CoV Ortholog
Jiyao Chen[SUP] 1 2 [/SUP], Zhuang Li[SUP] 1 2 [/SUP], Jiahui Guo[SUP] 1 2 [/SUP], Shangen Xu[SUP] 1 2 [/SUP], Junwei Zhou[SUP] 1 2 [/SUP], Qian Chen[SUP] 1 2 [/SUP], Xue Tong[SUP] 1 2 [/SUP], Dang Wang[SUP] 1 2 [/SUP], Guiqing Peng[SUP] 1 2 [/SUP], Liurong Fang[SUP] 1 2 [/SUP], Shaobo Xiao[SUP] 1 2 [/SUP]
Affiliations
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to pose an enormous threat to economic activity and public health worldwide. Previous studies have shown that the nonstructural protein 5 (nsp5, also called 3C-like protease) of alpha- and deltacoronaviruses cleaves Q231 of the NF-κB essential modulator (NEMO), a key kinase in the RIG-I-like receptor pathway, to inhibit type I interferon (IFN) production. In this study, we found that both SARS-CoV-2 nsp5 and SARS-CoV nsp5 cleaved NEMO at multiple sites (E152, Q205, and Q231). Notably, SARS-CoV-2 nsp5 exhibited a stronger ability to cleave NEMO than SARS-CoV nsp5. Sequence and structural alignments suggested that an S/A polymorphism at position 46 of nsp5 in SARS-CoV versus SARS-CoV-2 may be responsible for this difference. Mutagenesis experiments showed that SARS-CoV-2 nsp5 (S46A) exhibited poorer cleavage of NEMO than SARS-CoV-2 nsp5 wild type (WT), while SARS-CoV nsp5 (A46S) showed enhanced NEMO cleavage compared with the WT protein. Purified recombinant SARS-CoV-2 nsp5 WT and SARS-CoV nsp5 (A46S) proteins exhibited higher hydrolysis efficiencies than SARS-CoV-2 nsp5 (S46A) and SARS-CoV nsp5 WT proteins in vitro. Furthermore, SARS-CoV-2 nsp5 exhibited stronger inhibition of Sendai virus (SEV)-induced interferon beta (IFN-β) production than SARS-CoV-2 nsp5 (S46A), while introduction of the A46S substitution in SARS-CoV nsp5 enhanced suppression of SEV-induced IFN-β production. Taken together, these data show that S46 is associated with the catalytic activity and IFN antagonism by SARS-CoV-2 nsp5. IMPORTANCE The nsp5-encoded 3C-like protease is the main coronavirus protease, playing a vital role in viral replication and immune evasion by cleaving viral polyproteins and host immune-related molecules. We showed that both SARS-CoV-2 nsp5 and SARS-CoV nsp5 cleave the NEMO at multiple sites (E152, Q205, and Q231). This specificity differs from NEMO cleavage by alpha- and deltacoronaviruses, demonstrating the distinct substrate recognition of SARS-CoV-2 and SARS-CoV nsp5. Compared with SARS-CoV nsp5, SARS-CoV-2 nsp5 encodes S instead of A at position 46. This substitution is associated with stronger catalytic activity, enhanced cleavage of NEMO, and increased interferon antagonism of SARS-CoV-2 nsp5. These data provide new insights into the pathogenesis and transmission of SARS-CoV-2.
Keywords: 3C-like protease; NF-κB essential modulator (NEMO); catalytic activity; interferon; nonstructural protein 5 (nsp5); severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).
. 2022 Apr 7;e0003722.
doi: 10.1128/jvi.00037-22. Online ahead of print.
SARS-CoV-2 nsp5 Exhibits Stronger Catalytic Activity and Interferon Antagonism than Its SARS-CoV Ortholog
Jiyao Chen[SUP] 1 2 [/SUP], Zhuang Li[SUP] 1 2 [/SUP], Jiahui Guo[SUP] 1 2 [/SUP], Shangen Xu[SUP] 1 2 [/SUP], Junwei Zhou[SUP] 1 2 [/SUP], Qian Chen[SUP] 1 2 [/SUP], Xue Tong[SUP] 1 2 [/SUP], Dang Wang[SUP] 1 2 [/SUP], Guiqing Peng[SUP] 1 2 [/SUP], Liurong Fang[SUP] 1 2 [/SUP], Shaobo Xiao[SUP] 1 2 [/SUP]
Affiliations
- PMID: 35389264
- DOI: 10.1128/jvi.00037-22
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to pose an enormous threat to economic activity and public health worldwide. Previous studies have shown that the nonstructural protein 5 (nsp5, also called 3C-like protease) of alpha- and deltacoronaviruses cleaves Q231 of the NF-κB essential modulator (NEMO), a key kinase in the RIG-I-like receptor pathway, to inhibit type I interferon (IFN) production. In this study, we found that both SARS-CoV-2 nsp5 and SARS-CoV nsp5 cleaved NEMO at multiple sites (E152, Q205, and Q231). Notably, SARS-CoV-2 nsp5 exhibited a stronger ability to cleave NEMO than SARS-CoV nsp5. Sequence and structural alignments suggested that an S/A polymorphism at position 46 of nsp5 in SARS-CoV versus SARS-CoV-2 may be responsible for this difference. Mutagenesis experiments showed that SARS-CoV-2 nsp5 (S46A) exhibited poorer cleavage of NEMO than SARS-CoV-2 nsp5 wild type (WT), while SARS-CoV nsp5 (A46S) showed enhanced NEMO cleavage compared with the WT protein. Purified recombinant SARS-CoV-2 nsp5 WT and SARS-CoV nsp5 (A46S) proteins exhibited higher hydrolysis efficiencies than SARS-CoV-2 nsp5 (S46A) and SARS-CoV nsp5 WT proteins in vitro. Furthermore, SARS-CoV-2 nsp5 exhibited stronger inhibition of Sendai virus (SEV)-induced interferon beta (IFN-β) production than SARS-CoV-2 nsp5 (S46A), while introduction of the A46S substitution in SARS-CoV nsp5 enhanced suppression of SEV-induced IFN-β production. Taken together, these data show that S46 is associated with the catalytic activity and IFN antagonism by SARS-CoV-2 nsp5. IMPORTANCE The nsp5-encoded 3C-like protease is the main coronavirus protease, playing a vital role in viral replication and immune evasion by cleaving viral polyproteins and host immune-related molecules. We showed that both SARS-CoV-2 nsp5 and SARS-CoV nsp5 cleave the NEMO at multiple sites (E152, Q205, and Q231). This specificity differs from NEMO cleavage by alpha- and deltacoronaviruses, demonstrating the distinct substrate recognition of SARS-CoV-2 and SARS-CoV nsp5. Compared with SARS-CoV nsp5, SARS-CoV-2 nsp5 encodes S instead of A at position 46. This substitution is associated with stronger catalytic activity, enhanced cleavage of NEMO, and increased interferon antagonism of SARS-CoV-2 nsp5. These data provide new insights into the pathogenesis and transmission of SARS-CoV-2.
Keywords: 3C-like protease; NF-κB essential modulator (NEMO); catalytic activity; interferon; nonstructural protein 5 (nsp5); severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).