RRC ID 68387
Author Sasaki M, Uemura K, Sato A, Toba S, Sanaki T, Maenaka K, Hall WW, Orba Y, Sawa H.
Title SARS-CoV-2 variants with mutations at the S1/S2 cleavage site are generated in vitro during propagation in TMPRSS2-deficient cells.
Journal PLoS Pathog
Abstract The spike (S) protein of Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) binds to a host cell receptor which facilitates viral entry. A polybasic motif detected at the cleavage site of the S protein has been shown to broaden the cell tropism and transmissibility of the virus. Here we examine the properties of SARS-CoV-2 variants with mutations at the S protein cleavage site that undergo inefficient proteolytic cleavage. Virus variants with S gene mutations generated smaller plaques and exhibited a more limited range of cell tropism compared to the wild-type strain. These alterations were shown to result from their inability to utilize the entry pathway involving direct fusion mediated by the host type II transmembrane serine protease, TMPRSS2. Notably, viruses with S gene mutations emerged rapidly and became the dominant SARS-CoV-2 variants in TMPRSS2-deficient cells including Vero cells. Our study demonstrated that the S protein polybasic cleavage motif is a critical factor underlying SARS-CoV-2 entry and cell tropism. As such, researchers should be alert to the possibility of de novo S gene mutations emerging in tissue-culture propagated virus strains.
Volume 17(1)
Pages e1009233
Published 2021-1-1
DOI 10.1371/journal.ppat.1009233
PMID 33476327
PMC PMC7853460
MeSH Amino Acid Sequence Animals Caco-2 Cells Cell Line Chlorocebus aethiops HEK293 Cells Humans Mutation SARS-CoV-2 / classification SARS-CoV-2 / genetics* SARS-CoV-2 / growth & development SARS-CoV-2 / physiology Sequence Alignment Serial Passage Serine Endopeptidases / deficiency* Spike Glycoprotein, Coronavirus / genetics* Vero Cells Viral Tropism
IF 6.218
DNA material CSII-CMV-MCS-IRES2-Bsd (RDB04385) CSII-CMV-TMPRSS2-IRES2-Bsd (RDB19558)
Human and Animal Cells CACO-2(RCB0988)