tetano
Editor, Senior Moderator
Cell
. 2020 May 22;S0092-8674(20)30629-2.
doi: 10.1016/j.cell.2020.05.034. Online ahead of print.
Structural Basis for RNA Replication by the SARS-CoV-2 Polymerase
Quan Wang[SUP] 1 [/SUP], Jiqin Wu[SUP] 2 [/SUP], Haofeng Wang[SUP] 3 [/SUP], Yan Gao[SUP] 4 [/SUP], Qiaojie Liu[SUP] 2 [/SUP], An Mu[SUP] 5 [/SUP], Wenxin Ji[SUP] 5 [/SUP], Liming Yan[SUP] 4 [/SUP], Yan Zhu[SUP] 6 [/SUP], Chen Zhu[SUP] 6 [/SUP], Xiang Fang[SUP] 7 [/SUP], Xiaobao Yang[SUP] 6 [/SUP], Yucen Huang[SUP] 4 [/SUP], Hailong Gao[SUP] 5 [/SUP], Fengjiang Liu[SUP] 6 [/SUP], Ji Ge[SUP] 4 [/SUP], Qianqian Sun[SUP] 6 [/SUP], Xiuna Yang[SUP] 6 [/SUP], Wenqing Xu[SUP] 6 [/SUP], Zhijie Liu[SUP] 6 [/SUP], Haitao Yang[SUP] 6 [/SUP], Zhiyong Lou[SUP] 4 [/SUP], Biao Jiang[SUP] 6 [/SUP], Luke W Guddat[SUP] 8 [/SUP], Peng Gong[SUP] 9 [/SUP], Zihe Rao[SUP] 10 [/SUP]
Affiliations
Abstract
Nucleotide analog inhibitors, including broad-spectrum remdesivir and favipiravir, have shown promise in in vitro assays and some clinical studies for COVID-19 treatment, this despite an incomplete mechanistic understanding of the viral RNA-dependent RNA polymerase nsp12 drug interactions. Here, we examine the molecular basis of SARS-CoV-2 RNA replication by determining the cryo-EM structures of the stalled pre- and post- translocated polymerase complexes. Compared with the apo complex, the structures show notable structural rearrangements happening to nsp12 and its co-factors nsp7 and nsp8 to accommodate the nucleic acid, whereas there are highly conserved residues in nsp12, positioning the template and primer for an in-line attack on the incoming nucleotide. Furthermore, we investigate the inhibition mechanism of the triphosphate metabolite of remdesivir through structural and kinetic analyses. A transition model from the nsp7-nsp8 hexadecameric primase complex to the nsp12-nsp7-nsp8 polymerase complex is also proposed to provide clues for the understanding of the coronavirus transcription and replication machinery.
Keywords: 2019-nCoV; COVID-19; RdRP; SARS-CoV-2; favipiravir; nsp12; nsp8; polymerase; remdesivir; virus.
. 2020 May 22;S0092-8674(20)30629-2.
doi: 10.1016/j.cell.2020.05.034. Online ahead of print.
Structural Basis for RNA Replication by the SARS-CoV-2 Polymerase
Quan Wang[SUP] 1 [/SUP], Jiqin Wu[SUP] 2 [/SUP], Haofeng Wang[SUP] 3 [/SUP], Yan Gao[SUP] 4 [/SUP], Qiaojie Liu[SUP] 2 [/SUP], An Mu[SUP] 5 [/SUP], Wenxin Ji[SUP] 5 [/SUP], Liming Yan[SUP] 4 [/SUP], Yan Zhu[SUP] 6 [/SUP], Chen Zhu[SUP] 6 [/SUP], Xiang Fang[SUP] 7 [/SUP], Xiaobao Yang[SUP] 6 [/SUP], Yucen Huang[SUP] 4 [/SUP], Hailong Gao[SUP] 5 [/SUP], Fengjiang Liu[SUP] 6 [/SUP], Ji Ge[SUP] 4 [/SUP], Qianqian Sun[SUP] 6 [/SUP], Xiuna Yang[SUP] 6 [/SUP], Wenqing Xu[SUP] 6 [/SUP], Zhijie Liu[SUP] 6 [/SUP], Haitao Yang[SUP] 6 [/SUP], Zhiyong Lou[SUP] 4 [/SUP], Biao Jiang[SUP] 6 [/SUP], Luke W Guddat[SUP] 8 [/SUP], Peng Gong[SUP] 9 [/SUP], Zihe Rao[SUP] 10 [/SUP]
Affiliations
- PMID: 32526208
- DOI: 10.1016/j.cell.2020.05.034
Abstract
Nucleotide analog inhibitors, including broad-spectrum remdesivir and favipiravir, have shown promise in in vitro assays and some clinical studies for COVID-19 treatment, this despite an incomplete mechanistic understanding of the viral RNA-dependent RNA polymerase nsp12 drug interactions. Here, we examine the molecular basis of SARS-CoV-2 RNA replication by determining the cryo-EM structures of the stalled pre- and post- translocated polymerase complexes. Compared with the apo complex, the structures show notable structural rearrangements happening to nsp12 and its co-factors nsp7 and nsp8 to accommodate the nucleic acid, whereas there are highly conserved residues in nsp12, positioning the template and primer for an in-line attack on the incoming nucleotide. Furthermore, we investigate the inhibition mechanism of the triphosphate metabolite of remdesivir through structural and kinetic analyses. A transition model from the nsp7-nsp8 hexadecameric primase complex to the nsp12-nsp7-nsp8 polymerase complex is also proposed to provide clues for the understanding of the coronavirus transcription and replication machinery.
Keywords: 2019-nCoV; COVID-19; RdRP; SARS-CoV-2; favipiravir; nsp12; nsp8; polymerase; remdesivir; virus.