Figure 3.

Effects of additives and detergents on PDE6_t and PDE6 activity. A. Effects of reagents on PDE6_t and PDE6 activity. Activities of purified PDE6_t (upper panel) and PDE6 (lower panel) were measured in the absence (solid lines) or in the presence (dashed lines) of designated reagents. Urea (1 M, –▲–), Arginine (3 mM, –◆–), CaCl₂ (0.1M, –X–) and EDTA (5 mM, –◇–). The percentage of maximum PDE6_t activity vs. time is shown. B. Effects of selected detergents on PDE6 activity. The activities of PDE6_t (upper panel) were measured in the absence (solid line) or in the presence of specified detergents (dashed lines). C₈E₄ (10 mM, –○–), Anapoe X–100 (0.8 mM, –◇–), CHAPS (25 mM, –Δ–), n–octyl–β–D–glucopyranoside (20 mM, –◆–), n–dodecyl–N,N–dimethylamine–N-oxide (1 mM, – –) and dimethyldecylphosphine oxide (5 mM, –×–). Those detergents that did not alter PDE6_t activity were then tested for their ability to suppress PDE6 activity (lower panel). PDE6 without detergent (solid line), with detergents (dashed lines). N–undecyl–β–D–maltopyranoside (1 mM, –Δ–), C₈E₄ (10 mM, –○–), Anapoe X–100 (0.8 mM, –◇–). The percentage of cGMP hydrolyzed is plotted vs. time.