Figure 2.

Parasite growth depends on Gat1. Parasites were plated at clonal density on two-dimensional monolayers of HFFs and allowed to invade, proliferate, lyse out, and reinfect neighboring fibroblasts. After 5.5 days, cultures were fixed, stained, and analyzed for the areas occupied by lysed fibroblasts (plaques). Data from each of three independent trials, which were each normalized to the parental strain, were merged for presentation. A, comparison of the type 1 RH strain before and after gat1 replacement using CRISPR/Cas9 and complementation with gat1 under control of its own promoter cassette in the uprt locus. B, comparison of RHΔΔ, gat1-2Δ/RHΔΔ, and the latter complemented with gat1 under control of a tubulin promoter in the uprt locus. C, comparison of gat1-1Δ/RHΔΔ, prepared by homologous recombination. Significance of differences in plaque areas between parasite strains was assessed by Student's t test. CI, confidence interval.