As shown in Figure 1, compared to levels in control hippocampal neuronal cells, increased RhoA-guanosine triphosphate (GTP) levels were found in scrapie-infected mouse hippocampal neuronal cells (Figure 1A), which were used as an in vitro model of prion replication after infection with either of two mouse-derived scrapie strains (22L or 139A) [33,36]. Here, RHOA is linked to infection.