Figure 2.

Growth in cultured cells of RVFVs rA2 and rB3 carrying substitutions G924S & A1303T in the RdRp. Viral yield at 24, 48 and 72 hpi after infection at a MOI of 0.01 in (A) Vero and (B) HEK293T cells. Although coming from an independent experiment, a shade has been depicted to allow for a comparison with results shown in Figure 1 . In HEK293T infections, rZH548-P82L virus 2B7 was included for a comparison. Experiments were performed in duplicate. (C) Titer of supernatants collected at 72 hpi in serial passages (1 to 5) on Vero cells at a MOI of 0.01. Viral yields were determined by a plaque assay on Vero cell monolayers. (D) Sequence analysis of the RT-PCR product of viral RNAs recovered after 5 passages on Vero cells. The three nucleotide positions under study, 2788, 3166 and 3925, are shown. In the upper line, the wt sequence (rZH548) on the codons corresponding to residues 924, 1050 and 1303 is highlighted.