Figure 3.

IMPDH2 neurodevelopmental variants disrupt GTP inhibition. GTP inhibition of WT IMPDH2 and IMPDH2 neurodevelopmental variants. Each data point represents the average initial rate of three reactions. Error bars represent standard deviation for n = 3 technical replicates. Velocities were calculated from the change in absorbance at 340 nm. Reactions were initiated with 300 μM NAD+ and contained 1 μM enzyme, 1 mM ATP, 1 mM IMP, 1 mM MgCl_2, and varying concentrations of GTP. IMP, inosine 5′ monophosphate; IMPDH, inosine 5′ monophosphate dehydrogenase.