Structural highlights
Function
R1A_CVHNL The papain-like proteinase 1 (PLP1) and papain-like proteinase 2 (PLP2) are responsible for the cleavages located at the N-terminus of the replicase polyprotein. In addition, PLP2 possesses a deubiquitinating/deISGylating activity and processes both 'Lys-48'- and 'Lys-63'-linked polyubiquitin chains from cellular substrates. PLP2 also antagonizes innate immune induction of type I interferon by blocking the nuclear translocation of host IRF-3. The main proteinase 3CL-PRO is responsible for the majority of cleavages as it cleaves the C-terminus of replicase polyprotein at 11 sites. Recognizes substrates containing the core sequence [ILMVF]-Q-|-[SGACN]. Inhibited by the substrate-analog Cbz-Val-Asn-Ser-Thr-Leu-Gln-CMK. Also contains an ADP-ribose-1-phosphate (ADRP)-binding function (By similarity). Nsp7-nsp8 hexadecamer may possibly confer processivity to the polymerase, maybe by binding to dsRNA or by producing primers utilized by the latter (By similarity). Nsp9 is a ssRNA-binding protein (By similarity).
Publication Abstract from PubMed
First identified in The Netherlands in 2004, human coronavirus NL63 (HCoV-NL63) was found to cause worldwide infections. Patients infected by HCoV-NL63 are typically young children with upper and lower respiratory tract infection, presenting with symptoms including croup, bronchiolitis, and pneumonia. Unfortunately, there are currently no effective antiviral therapy to contain HCoV-NL63 infection. CoV genomes encode an integral viral component, main protease (M(pro)), which is essential for viral replication through proteolytic processing of RNA replicase machinery. Due to the sequence and structural conservation among all CoVs, M(pro) has been recognized as an attractive molecular target for rational anti-CoV drug design. Here we present the crystal structure of HCoV-NL63 M(pro) in complex with a Michael acceptor inhibitor N3. Structural analysis, consistent with biochemical inhibition results, reveals the molecular mechanism of enzyme inhibition at the highly conservative substrate-recognition pocket. We show such molecular target remains unchanged across 30 clinical isolates of HCoV-NL63 strains. Through comparative study with M(pro)s from other human CoVs (including the deadly SARS-CoV and MERS-CoV) and their related zoonotic CoVs, our structure of HCoV-NL63 M(pro) provides critical insight into rational development of wide spectrum antiviral therapeutics to treat infections caused by human CoVs.
Structure of Main Protease from Human Coronavirus NL63: Insights for Wide Spectrum Anti-Coronavirus Drug Design.,Wang F, Chen C, Tan W, Yang K, Yang H Sci Rep. 2016 Mar 7;6:22677. doi: 10.1038/srep22677. PMID:26948040[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Wang F, Chen C, Tan W, Yang K, Yang H. Structure of Main Protease from Human Coronavirus NL63: Insights for Wide Spectrum Anti-Coronavirus Drug Design. Sci Rep. 2016 Mar 7;6:22677. doi: 10.1038/srep22677. PMID:26948040 doi:http://dx.doi.org/10.1038/srep22677
