title: Phytohormone-regulated beta-amylase gene expression in rice.
abstract: The expression of beta-amylase genes in rice (Oryza sativa) and its regulation by phytohormones gibberellic acid (GA) and abscisic acid (ABA) were examined. Upon germination beta-amylase is synthesized de novo in aleurone cells and (GA) is not required. Exogenous addition of GA does not enhance the beta-amylase activity, while ABA inhibits the beta-amylase activity, mRNA accumulation, and the germination of rice seeds. GA can reverse ABA inhibition of beta-amylase expression, but not ABA inhibition of seed germination. Such regulation represents a new interaction of ABA and GA.
authors.affiliation: Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan.
authors.forename: S M
authors.initials: SM
authors.lastname: Wang
authors.forename: W L
authors.initials: WL
authors.lastname: Lue
authors.forename: K
authors.initials: K
authors.lastname: Eimert
authors.forename: J
authors.initials: J
authors.lastname: Chen
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology*; D002523:Edible Grain / Q000235:genetics; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D018525:Germination / Q000187:drug effects; D005875:Gibberellins / Q000494:pharmacology*; D012275:Oryza / Q000187:drug effects / Q000201:enzymology / Q000235:genetics*; D010937:Plant Growth Regulators / Q000494:pharmacology*; D012333:RNA, Messenger / Q000032:analysis; D001614:beta-Amylase / Q000096:biosynthesis* / Q000235:genetics
chemical_list: D005875:Gibberellins; D010937:Plant Growth Regulators; D012333:RNA, Messenger; D000040:Abscisic Acid; C007842:gibberellic acid; D001614:beta-Amylase