Pin1 sirna

VeroE6/TMPRSS2 cells (African green monkey kidney-derived cells expressing human TMPRSS2, purchased from the Japanese Collection of Research Bioresources (JCRB) Cell Bank, JCRB1819) were maintained in Dulbecco's Modi ed Eagle's Medium (DMEM) containing 10% fetal bovine serum (FBS) and 1 mg/mL G418 at 37°C in 5% CO 2 . For siRNA treatment, VeroE6/TMPRSS2 cells were transfected with either negative siRNA (QIAGEN) or Pin1 siRNA (Invitrogen) using RNAiMAX (Invitrogen) according to the manufacturer's protocol and subjected to SARS-CoV-2 infection 3 days later. Pin1 siRNA1: CCG UGU UCA CGG AUU CCG GCA UCC A. Pin1 siRNA2: GCC CUG GAG CUG AUC AAC GGC UAC A. Pin1 inhibitors Chemical structures of Pin1 inhibitors termed H-77, H-175, H-363, H-371 and H-593 are shown in Table 1. These Pin1 inhibitors inhibit isomerase activity by more than 80% at a concentration of 20 µM, based on an in vitro assay using recombinant Pin1 protein. However, it should be noted that the results of such an in vitro assay usually differ signi cantly from the results obtained by in vivo experiments. The compounds were solubilized in DMSO. Before the infection experiments, the culture medium of VeroE6/TMPRSS2 cells was changed to DMEM without FBS and G-418, and virus and/or Pin1 inhibitors were added at the indicated titer or concentrations.