Table 1.

GTP-dependent adenylyl cyclase activity in control (cn, ry) flies and flies expressing the activated G_s α subunit

	Gsα* pmol/mg	Control prot/min
Background	90 ± 4	100 ± 9
GTP	720 ± 38**	88 ± 8
AlF4	1530 ± 67	1600 ± 72
GTP-γS	1030 ± 43	1250 ± 52

Cyclase activity was assayed in the absence (background) or presence of 50 μm GTP, 1mm AlF₄, or 10 μm GTP-γS. The data are the mean ± SD of three determinations. The data are from a typical experiment that was repeated three times with essentially the same results. Note the greatly increased GTP-dependent activity in G_sα* flies (**p <0.001). Background activity and maximal activity (in the presence of AlF₄ or GTP-γS) were unaffected.