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bioRxiv · 10.1101/363432

A Virus-Packageable CRISPR Screen Identifies Host Factors Mediating Interferon Inhibition of HIV

Ohainle, M.·Pendergast, L.·Vermeire, J.·Roesch, F.·Humes, D.·Basom, R.·Delrow, J. J.·Overbaugh, J.·Emerman, M.
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Abstract

Interferon (IFN) inhibits HIV replication by inducing an array of antiviral effectors. Here we describe a novel CRISPR knockout screening approach to identify the ensemble of these HIV restriction factors. We assembled a CRISPR sgRNA library specific for Interferon Stimulated Genes (ISGs) into a modified lentiviral vector that allows for packaging of sgRNA-encoding genomes in trans into budding HIV-1 particles. We observed that knockout of Zinc Antiviral Protein (ZAP) improved the performance of the screen due to ZAP-mediated inhibition of the vector. We identify a small panel of IFN-induced HIV restriction factors, including MxB, IFITM1, Tetherin/BST2 and TRIM5 which together explain the inhibitory effects of IFN on the HIV-1 LAI strain in THP-1 cells. Further, we identify novel HIV dependency factors, including SEC62 and TLR2. The ability of IFN-induced restriction factors to inhibit an HIV strain to replicate in human cells suggests that these human restriction factors are incompletely antagonized.

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Ohainle, M., Pendergast, L., Vermeire, J., Roesch, F., Humes, D., Basom, R., Delrow, J. J., Overbaugh, J., Emerman, M.. 2018-07-20. A Virus-Packageable CRISPR Screen Identifies Host Factors Mediating Interferon Inhibition of HIV. https://doi.org/10.1101/363432

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