Fig. 4

Effects of teriflunomide on minigenome replication and transcription. a De novo pyrimidine synthesis pathway. The production of uridine monophosphate from hydrogencarbonate, ammonia, and ATP by carbamoyl-phosphate synthetase 2, aspartate transcarbamylase, and dihydroorotase (CAD), dihydroorotate dehydrogenase (DHODH), and uridine monophosphate synthetase (UMPS) is shown, and the reaction blocked by teriflunomide is indicated. b Influence of knockdown of enzymes in the de novo pyrimidine synthesis pathway on minigenome activity in the primary siRNA screen. A subset of the data from Fig. 2a), comprising data for siRNAs against CAD, DHODH, and UMPS, is shown. c Effect of teriflunomide on ebolavirus minigenome replication and transcription. An ebolavirus minigenome assay was performed in the presence of various concentrations of teriflunomide, as indicated, using Renilla luciferase (hrLuc) as a readout for minigenome replication and transcription, and firefly (FF) luciferase expression as a readout for plasmid-driven gene expression. As a negative control, the viral polymerase was omitted (−L). Means and standard deviations from 3 independent experiments are shown. d Substrate rescue experiment with orotic acid. Minigenome assays were performed as indicated in panel c in the presence of 3.13 μM teriflunomide (TF), with increasing amounts of orotic acid (OA) added, as indicated. Means and standard deviations from 5 independent experiments are shown. p values from paired two-tailed t-tests are indicated