African green monkey kidney Vero E6 cells (ATCC; CRL-1586) and human hepatocarcinoma Huh-7 cells (JCRB, 0403) were cultured in Dulbecco’s modified Eagle medium (DMEM; Sigma-Aldrich; D5796) containing 10% fetal bovine serum (FBS; Invitrogen; 10270), 50 U ml−1 of penicillin, and 50 μg ml−1 of streptomycin. The Atg5−/− Vero E6 cell line was purchased from Ubigene Biosciences (Guangzhou, China) and maintained in the same growth medium as described above.
The SARS-CoV-2 strain BetaCoV/Beijing/IME-BJ01/2020 was originally isolated by C. F. Qin’s laboratory (Beijing, China) as described previously (24 (link)). Virus stocks were propagated and titers were determined on Vero E6 cells. All experiments with infectious SARS-CoV-2 virus were conducted in a biosafety level 3 laboratory in the Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences.
3-MA (HY-19312), rapamycin (HY-10219), E64D (HY-100229), pepstatin A (HY-P0018), SAR405 (HY-12481), and VPS34-IN-2 (HY-12473) were purchased from MedChemExpress (Monmouth Junction, NJ). VPS34-IN-1 (A15874) was purchased from Adooq Bioscience (Irvine, CA). CQ (C6628) was purchased from Sigma-Aldrich (St. Louis, MO).