Figure 5
From: Functional characterisation of a novel class of in-frame insertion variants of KRAS and HRAS
VMOS RAS variants displayed reduced GTPase activity. (A,B) The GTP fraction p(GTP) of the total nucleotide load of wild type and mutated HRAS (A) and KRAS (B) was followed over time. The time dependent decay of p(GTP) was fitted as single exponential decay (solid line) to determine the rate of intrinsic GTP hydrolysis kintrinsic. (C) Intrinsic GTP hydrolysis rates kintrinsic as determined in (A,B). (D,E) RasGAP catalysed GTPase activity of wild type and variant HRAS (D) and KRAS (E). p(GTP) was determined at time zero and after τ = 70 minutes of incubation in the presence of various concentration of RasGAP. Wild type RAS was in addition analysed after τ = 20 minutes. Solid lines connect the data points belonging to the series of a RAS variant. (F,G) Time dependent GTP hydrolysis of KRAS wt (F) and KRAS (G) in the presence of various RasGAP concentration. The dependent decay of p(GTP) was fitted as single exponential decay (solid line) to obtain kobs. Note: Different scales are used in (F,G). (H) kobs as obtained in (F,G) were plotted against the concentration of RasGAP. Solid lines connect the data point belonging to one series.
