Cells were lysed in ice-cold whole-cell extract buffer as described previously.53 Antibodies used are LC3 (L7543, Sigma), ATG16L1 (ab106354, Abcam, Cambridge, UK), BECN1 (#3738, Cell Signaling Technology, Danvers, CA, USA), SQSTM1/p62 (610832, BD Biosciences, Franklin Lakes, NJ, USA), OPTN (A301-831A-T, Bethyl Laboratories, Montgomery, TX, USA), γH2AX (05-636, Millipore, Billerica, MA, USA), GAPDH (Proteintech, Wuhan, China), ACTB (SAB1403520, Sigma), HRP-conjugated secondary antibodies (KPL, Milford, MA, USA). Protein bands were visualized by chemiluminescence (Thermo Scientific, Rockford, IL, USA).