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Emergence of SARS-CoV-2 through recombination and strong purifying selection.

ABSTRACT: COVID-19 has become a global pandemic caused by the novel coronavirus SARS-CoV-2. Understanding the origins of SARS-CoV-2 is critical for deterring future zoonosis, discovering new drugs, and developing a vaccine. We show evidence of strong purifying selection around the receptor binding motif (RBM) in the spike and other genes among bat, pangolin, and human coronaviruses, suggesting similar evolutionary constraints in different host species. We also demonstrate that SARS-CoV-2's entire RBM was introduced through recombination with coronaviruses from pangolins, possibly a critical step in the evolution of SARS-CoV-2's ability to infect humans. Similar purifying selection in different host species, together with frequent recombination among coronaviruses, suggests a common evolutionary mechanism that could lead to new emerging human coronaviruses.

SUBMITTER: Li X

PROVIDER: S-EPMC7458444 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Emergence of SARS-CoV-2 through recombination and strong purifying selection.

Li Xiaojun X Giorgi Elena E EE Marichannegowda Manukumar Honnayakanahalli MH Foley Brian B Xiao Chuan C Kong Xiang-Peng XP Chen Yue Y Gnanakaran S S Korber Bette B Gao Feng F

Science advances 20200701 27

COVID-19 has become a global pandemic caused by the novel coronavirus SARS-CoV-2. Understanding the origins of SARS-CoV-2 is critical for deterring future zoonosis, discovering new drugs, and developing a vaccine. We show evidence of strong purifying selection around the receptor binding motif (RBM) in the spike and other genes among bat, pangolin, and human coronaviruses, suggesting similar evolutionary constraints in different host species. We also demonstrate that SARS-CoV-2's entire RBM was ...[more]

PMID: 32937441

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Multiple Recombination Events and Strong Purifying Selection at the Origin of SARS-CoV-2 Spike Glycoprotein Increased Correlated Dynamic Movements.

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