A speed–fidelity trade-off determines the mutation rate and virulence of an RNA virus
Fitness values (≥3 replicate competition assays for each data point) were determined for populations from every fifth passage (panel A) or every fourth passage (panel B), and the adaptability in the top panels was expressed as the slope of the regression for log10 fitness over time for each of 5 independent lineages of WT (filled circles) and 3DG64S (open circles, blue) for each cell line. The bottom panels show all the data from the 5 lineages together with the regression of log10 fitness over time. Exact p-values for the difference between the slopes for WT and 3DG64S on HeLa (0.0129) and PVR-3T3 (0.0013) were derived from a mixed linear effects model (see Methods). All plotted data can be found in SI, S1 Data. HeLa, human epithelial cells; PVR, poliovirus receptor; WT, wild-type.