Orthogonal genome-wide screenings in bat cells identify MTHFD1 as a target of broad antiviral therapy

Danielle E Anderson; Jin Cui; Qian Ye; Baoying Huang; Wenhong Zu; Jing Gong; Weiqiang Liu; So Young Kim; Biao Guo Yan; Kristmundur Sigmundsson; Xiao Fang Lim; Fei Ye; Peihua Niu; Xuming Zhou; Wenjie Tan; Lin-Fa Wang; Xu Tan

We performed a CRISPR screen with influenza A virus in PaKi cells to identify viral host factors 14 ( Fig. 1a) . PaKi cells stably expressing SgCas9 and sgRNA library were infected with the H1N1 15 PR8 strain of influenza A virus, in duplicate. We used a high multiplicity-of-infection (MOI) so 16 that naïve PaKi cells all died before the 9th day post infection. We then collected the surviving 17 cells and compared sgRNA abundance with mock-infected cells. The two replicates demonstrated 18 a high correlation, indicating high reproducibility (Supplementary Fig. 2) . We calculated the 19 results using the RIGER algorithm and identified 21 host factors required for the viral infection or 20 pathogenesis 20 (Fig. 1b) . Three of the top four hits belong to the V-type proton ATPase subunits 21 (ATP6V1B2, ATP6V1F and ATP6V0D1), which are involved in the acidification of endosome 22