Opteka stabilizing handle
Previously, ABA-GE was considered a permanently inactivated form, but recent studies indicate that it is a storage or transport form of ABA. Compounds with a nitrogen-containing heterocycle, such as triazoles and imidazoles, are known to act as inhibitors of various P-450 enzyme-mediated hydroxylation events. Among them, S -uniconazole (UNI; Fig.
1 ), a plant growth retardant developed in the 1980s 18, inhibits CYP707A 19 and ent -kaurene oxidase (CYP701A), which catalyses the three-step oxidation of ent -kaurene to ent -kaurenoic acid (KA) 20, a biosynthetic precursor of the plant hormone gibberellin (GA). Hence, treatment with UNI reduces water loss and enhances drought tolerance 19; however, its low specific inhibition of P-450 enzymes limits its potential use as a chemical probe and in practical applications.