Identification of Required Host Factors for SARS-CoV-2 Infection in Human Cells

To better understand host-virus genetic dependencies and find potential therapeutic targets for COVID-19, we performed a genome-scale CRISPR loss-of-function screen to identify host factors required for SARS-CoV-2 viral infection of human alveolar epithelial cells. Top-ranked genes cluster into distinct pathways, including the vacuolar ATPase proton pump, Retromer, and Commander complexes. We validate these gene targets using several orthogonal methods such as CRISPR knockout, RNA interference knockdown, and small-molecule inhibitors. Using single-cell RNA-sequencing, we identify shared transcriptional changes in cholesterol biosynthesis upon loss of top-ranked genes. In addition, given the key role of the ACE2 receptor in the early stages of viral entry, we show that loss of RAB7A reduces viral entry by sequestering the ACE2 receptor inside cells. Overall, this work provides a genome-scale, quantitative resource of the impact of the loss of each host gene on fitness/response to viral infection.

Automated summary

Researchers conducted a genome-scale CRISPR screen to identify host factors crucial for SARS-CoV-2 infection, highlighting genes related to ATPase proton pump, Retromer, and Commander complexes. Validating these gene targets through multiple methods, they found shared transcriptional changes in cholesterol biosynthesis when top-ranked genes were lost. Loss of RAB7A was shown to reduce viral entry by sequestering the ACE2 receptor inside cells, underscoring its importance early in the viral infection process.