A novel cell culture system modeling the SARS-CoV-2 life cycle

• DOI: 10.1371/journal.ppat.1009439
• Publication Date: 2021-03-12T18:38:40Z
• Authors: Xiaohui Ju; Yunkai Zhu; Yuyan Wang; Jingrui Li; Jiaxing Zhang; Mingli Gong; Wenlin Ren; Sai Li; Jin Zhong; Linqi Zhang; Qiangfeng Cliff Z...; Rong Zhang; Qiang Ding
• Keywords: Viral life cycle; Biosafety; Coronavirus

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes the global pandemic of COVID-19. SARS-CoV-2 is classified as a biosafety level-3 (BSL-3) agent, impeding basic research into its biology and development effective antivirals. Here, we developed level-2 (BSL-2) cell culture system for production transcription replication-competent virus-like-particles (trVLP). This trVLP expresses reporter gene (GFP) replacing viral nucleocapsid (N), which required genome packaging virion assembly (SARS-CoV-2 GFP/ΔN trVLP). The complete life cycle can be achieved exclusively confined in cells ectopically expressing SARS-CoV or N proteins, but not MERS-CoV N. Genetic recombination supplied trans was detected, evidenced by sequence analysis after one-month serial passages N-expressing cells. Moreover, intein-mediated protein trans-splicing approach utilized to split two independent vectors, ligated could function recapitulate entire cycle, further securing this model. Based on BSL-2 model, 96-well format high throughput screening antivirals discovery. We identified salinomycin, tubeimoside I, monensin sodium, lycorine chloride nigericin sodium potent against infection. Collectively, convenient efficient reverse genetics tool dissect virus under condition. powerful should accelerate our understanding antiviral development.