Ap1 luciferase construct

Cells were sub-cultured in 6-well plate at ~60% confluency and transfected with plasmid DNA (pcDNA3.1-SARS-CoV-2-Spike MC-0101087-5834, kindly provided from BEI Resources), pCMV3-SARS-CoV-2-Spike S1 region or pCMV3-SARS-CoV-2-Spike S2 region (Sino Biological), and empty vector construct (500 ng/plate) using Lipofectamine 3000 (Life Technologies) following the manufacturer’s instruction. Cell lysates were prepared after 48 h of transfection for analyses. AP1-luciferase construct was obtained from commercial source (Addgene) and used in luciferase assay.

Six-week-old ICR, Balb/c, and C57BL/6 male mice (see Table S2 for genetic background information) were purchased from Daehan Biolink (DBL, Chungbuk, Korea) and housed eight mice per group under a 12-h light/dark cycle (lights on at 6 a.m.). Water and a pellet diet (Samyang, Daejeon, Korea) were supplied ad libitum. Animal care followed guidelines issued by the National Institutes of Health for the Care and Use of Laboratory Animals (NIH Publication 80-23, revised in 1996) and the Institutional Animal Care and Use Committee at Sungkyunkwan University (Approval No.: SKKUIACUC-2016-01-0002-2). Phorbol-12-myristate, sodium carboxyl methylcellulose, 2,4-dinitrochlorobenzene (DNCB), dextran sodium sulphate (DSS), acetylsalicylic acid, D-GalN, LPS (E. coli 0111:B4), 100% EtOH, and HCl were purchased from Sigma Chemical Co. (St. Louis, MO, USA). MAPK inhibitors (SB203580, SP600125, and U0126) were purchased from Calbiochem (La Jolla, CA, USA). RAW264.7, HEK293, and MDA-MB-231 cells were purchased from the American Type Culture Collection (Manassas, VA, USA). Detailed information on antibodies used in this study is explained in Supplementary Materials. The AP-1 luciferase construct was purchased from Addgene (Cambridge, MA, USA).