Different residues in the SARS-CoV spike protein determine cleavage and activation by the host cell protease TMPRSS2.

Different residues in the SARS-CoV spike protein determine cleavage and activation by the host cell protease TMPRSS2.

Lennart Michel Reinke, Martin Spiegel, Teresa Plegge, Anika Hartleib, Inga Nehlmeier, Stefanie Gierer, Markus Hoffmann, Heike Hofmann-Winkler, Michael Winkler, Stefan Pöhlmann

The spike (S) protein of severe acute respiratory syndrome coronavirus (SARS-CoV) mediates viral entry into target cells. Cleavage and activation of SARS S by a host cell protease is essential for infectious viral entry and the responsible enzymes are potential targets for antiviral intervention. The type II transmembrane serine protease TMPRSS2 cleaves and activates SARS S in cell culture and potentially also in the infected host. Here, we investigated which determinants in SARS S control cleavage and activation by TMPRSS2. We found that SARS S residue R667, a previously identified trypsin cleavage site, is also required for S protein cleavage by TMPRSS2. The cleavage fragments produced by trypsin and TMPRSS2 differed in their decoration with N-glycans, suggesting that these proteases cleave different SARS S glycoforms. Although R667 was required for SARS S cleavage by TMPRSS2, this residue was dispensable for TMPRSS2-mediated S protein activation. Conversely, residue R797, previously reported to be required for SARS S activation by trypsin, was dispensable for S protein cleavage but required for S protein activation by TMPRSS2. Collectively, these results show that different residues in SARS S control cleavage and activation by TMPRSS2, suggesting that these processes are more complex than initially appreciated.

2017

DOI: 10.1371/journal.pone.0179177

PLoS ONE

Public Library of Science (PLoS)

Science, Medicine

EN