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bioRxiv · 10.1101/2021.06.28.450244

Systematic genome-scale identification of host factors for SARS-CoV-2 infection across models yields a core single gene dependency; ACE2

Abstract

SARS-CoV-2, depends on host cell components for replication, therefore the identification of virus-host dependencies offers an effective way to elucidate mechanisms involved in viral infection. Such host factors may be necessary for infection and replication of SARS-CoV-2 and, if druggable, presents an attractive strategy for anti-viral therapy. We performed genome wide CRISPR knockout screens in Vero E6 cells and 4 human cell lines including Calu-3, Caco-2, Hek293 and Huh7 to identify genetic regulators of SARS-CoV-2 infection. Our findings identified only ACE2, the cognate SARS-CoV-2 entry receptor, as a common host dependency factor across all cell lines, while all other host genes identified were cell line specific including known factors TMPRSS2 and CTSL. Several of the discovered host-dependency factors converged on pathways involved in cell signalling, lipid metabolism, immune pathways and chromatin modulation. Notably, chromatin modulator genes KMT2C and KDM6A in Calu-3 cells had the strongest impact in preventing SARS-CoV-2 infection when perturbed. Overall, the network of host factors that have been identified will be broadly applicable to understanding the impact of SARS-CoV-2 on human cells and facilitate the development of host-directed therapies. IN BRIEFSARS-CoV-2, depends on host cell components for infection and replication. Genome-wide CRISPR screens were performed in multiple human cell lines to elucidate common host dependencies required for SARS-CoV-2 infection. Only ACE2, the cognate SARS-CoV-2 entry receptor, was common amongst cell lines, while all other host genes identified were cell line specific, several of which converged on pathways involved in cell signalling, lipid metabolism, immune pathways, and chromatin modulation. Overall, a network of host factors was identified that will be broadly applicable to understanding the impact of SARS-CoV-2 on human cells and facilitate productive targeting of host genes and pathways. HIGHLIGHTS- Genome-wide CRISPR screens for SARS-CoV-2 in multiple human cell lines - Identification of wide-ranging cell-type dependent genetic dependencies for SARS-CoV-2 infection - ACE2 is the only common host factor identified across different cell types

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BibTeXRIS

Chan, K., Farias, A. G., Lee, H., Guvenc, F., Mero, P., Aulakh, K., Brown, K. R., Haider, S., Marcon, E., Braunschweig, U., Tong, A. H. Y., Pu, S., Habsid, A., Christie-Holmes, N., Budylowski, P., Astori, A., Ghalami, A., Mubareka, S., Banerjee, A., Mossman, K. L., Greenblatt, J., Gray-Owen, S. D., Raught, B., Blencowe, B., Taiplale, M., Moffat, J.. 2021-06-29. Systematic genome-scale identification of host factors for SARS-CoV-2 infection across models yields a core single gene dependency; ACE2. https://doi.org/10.1101/2021.06.28.450244

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