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bioRxiv · 10.1101/2020.08.25.266775

The S1/S2 boundary of SARS-CoV-2 spike protein modulates cell entry pathways and transmission

Zhu, Y.·Feng, F.·Hu, G.·Wang, Y.·Yu, Y.·Xu, W.·Cai, X.·Sun, Z.·Han, W.·Ye, R.·Chen, H.·Ding, Q.·Cai, Q.·Qu, D.·Xie, Y.·Yuan, Z.·Zhang, R.
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Abstract

The global spread of SARS-CoV-2 is posing major public health challenges. One unique feature of SARS-CoV-2 spike protein is the insertion of multi-basic residues at the S1/S2 subunit cleavage site, the function of which remains uncertain. We found that the virus with intact spike (Sfull) preferentially enters cells via fusion at the plasma membrane, whereas a clone (Sdel) with deletion disrupting the multi-basic S1/S2 site instead utilizes a less efficient endosomal entry pathway. This idea was supported by the identification of a suite of endosomal entry factors specific to Sdel virus by a genome-wide CRISPR-Cas9 screen. A panel of host factors regulating the surface expression of ACE2 was identified for both viruses. Using a hamster model, animal-to-animal transmission with the Sdel virus was almost completely abrogated, unlike with Sfull. These findings highlight the critical role of the S1/S2 boundary of the SARS-CoV-2 spike protein in modulating virus entry and transmission.

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Zhu, Y., Feng, F., Hu, G., Wang, Y., Yu, Y., Xu, W., Cai, X., Sun, Z., Han, W., Ye, R., Chen, H., Ding, Q., Cai, Q., Qu, D., Xie, Y., Yuan, Z., Zhang, R.. 2020-08-25. The S1/S2 boundary of SARS-CoV-2 spike protein modulates cell entry pathways and transmission. https://doi.org/10.1101/2020.08.25.266775

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