Involved in the oxidative degradation of abscisic acid, but not in the isomerization of the produced 8'-hydroxyabscisic acid (8'-OH-ABA) to (-)-phaseic acid (PA). Involved in the control of seed dormancy and germination. 2-cis-(+)-abscisate + O2 + reduced [NADPH--hemoprotein reductase] = (+)-8'-hydroxyabscisate + H(+) + H2O + oxidized [NADPH--hemoprotein reductase] Plant hormone degradation; abscisic acid degradation. Mainly expressed in dry seeds. Lower expression in rosette leaves, flowers, siliques and stems. Not expressed in roots. Expressed in both endosperm and vascular tissues of embryo during the seed development and in cortex and endodermis in germinating embryo. Up-regulated from late-maturation to mature dry seed. Up-regulated immediately after seed imbibition, reaching a maximum at 6 hours and decreasing therafter. By abscisic acid, dehydration and rehydration. Expression regulated by phytochrome B. Plants show a hyperdormancy phenotype. Belongs to the cytochrome P450 family.