claim: furin cleavage of sars-cov-2 spike promotes but is still essential for infection and cell-cell fusion
evidence_1: here we show that crispr- cas9 knockout of furin reduces, but does not prevent, the production of infectious sars-cov-2 virus.", "comparing s processing in furin knockout cells to multibasic site mutants reveals that while loss of furin substantially reduces s1-s2 cleavage it does not prevent it.", "our results show that while furin promotes both sars-cov-2 infectivity and cell-cell spread it is not essential, suggesting furin inhibitors will not prevent viral spread.", "we show that loss of furin in either donor or acceptor cells reduces, but does not prevent, tmprss2-dependent cell-cell fusion, unlike mutation of the multibasic site that completely prevents syncytia formation."
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
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