Table 1.

Quantification of Gα_o binding affinity of RGS18 mutants^a

	KD (nM)b
RGS18	>3000c
RGS18a	>3000c
RGS18b	240±70
RGS18c	215±45
RGS18d	230±80
RGS18e	69±6

^aGα_o is bound to the transition state analog GDP–aluminum fluoride.

^bK_D values were calculated as weighed averages ± s.e.m. from 2–3 independent experiments (see Methods for details)

^cThese K_D values are underestimations because dose response saturation was not reached.