High glucose

Human embryonic kidney 293T (HEK293T) cells were purchased from the American Type Culture Collection (ATCC, USA) and maintained in Dulbecco's Modified Eagle's Medium DMEM (High-glucose, Welgene, Korea) supplemented with 10% fetal bovine serum (FBS, Welgene) and 1% penicillin/streptomycin (Thermo Fisher Sicentific, USA) [51, 52] . Cells were incubated at 37°C in a humidifying 5% CO 2 incubator [35, 53, 54] . Restriction enzymes for cloning were purchased from either Enzynomics (Korea) or New England Biolabs (NEB, USA). Firefly luciferase and Beta-Glo Assay System for luciferase assay [34] were procured from Promega (USA). Anti-FLAG antibody (M2) was purchased from Millipore Sigma (USA) and used at 1:5000 dilution. The following antibodies were obtained from Cell Signaling (USA): HA tag-specific mouse monoclonal antibody (6E2, 1/1000), horseradish peroxidase (HRP)-conjugated rabbit monoclonal anti-GAPDH antibody (14C10, 1/2000), HRP-conjugated anti-mouse IgG antibody (1/2000) .