Chapter 8 - Abscisic acid metabolism and its regulation

摘要: Abscisic acid (ABA) was originally isolated by Addicott and associates, at the University of California, Davis, from young cotton fruits that abscised prematurely. It is now recognized ABA has little, if any, role in processes abscission bud dormancy. Like other plant hormones, multiple functions growth development. Studies with ABA-deficient mutants have indicated plays a water relations as an endogenous antitranspirant, embryo seed Consequently, readily wilt their immature embryos germinate prematurely (vivipary). also response to environmental stresses, such drought, cold, heat, salinity, through its ability induce expression specific genes. Recent evidence established that, higher plants, apocarotenoid formed oxidative cleavage C 40 , precursor form XAN, which converted via ABA-ald ABA. Nevertheless, many details pathway remain be worked out, isomenzation all-trans- 9-cis-xanthophylls, vivo substrate reaction, well cellular location. The epoxy-carotenoids XAN first committed step biosynthesis presumably key regulatory step. Knowledge biosynthetic may lead modification ABA-mediated altering levels plants.