title: Endogenous factors regulating poor-nutrition stress-induced flowering in pharbitis: The involvement of metabolic pathways regulated by aminooxyacetic acid.
abstract: The short-day plant pharbitis (also called Japanese morning glory), Ipomoea nil (formerly Pharbitis nil), was induced to flower by poor-nutrition stress. This stress-induced flowering was inhibited by aminooxyacetic acid (AOA), which is a known inhibitor of phenylalanine ammonia-lyase (PAL) and the synthesis of indole-3-acetic acid (IAA) and 1-aminocycropropane-1-carboxylic acid (ACC) and thus regulates endogenous levels of salicylic acid (SA), IAA and polyamine (PA). Stress treatment increased PAL activity in cotyledons, and AOA suppressed this increase. The observed PAL activity and flowering response correlate positively, indicating that AOA functions as a PAL inhibitor. The inhibition of stress-induced flowering by AOA was also overcome by IAA. An antiauxin, 4-chlorophenoxy isobutyric acid, inhibited stress-induced flowering. Both SA and IAA promoted flowering induced by stress. PA also promoted flowering, and the effective PA was found to be putrescine (Put). These results suggest that all of the pathways leading to the synthesis of SA, IAA and Put are responsive to the flowering inhibition by AOA and that these endogenous factors may be involved in the regulation of stress-induced flowering. However, as none of them induced flowering under non-stress conditions, they may function cooperatively to promote flowering.
authors.affiliation: Graduate School of Science and Technology, Niigata University, Ikarashi, Nishi-ku, Niigata, Niigata 950-2181, Japan.
authors.forename: Aya
authors.initials: A
authors.lastname: Koshio
authors.affiliation: Department of Biology, Faculty of Science, Niigata University, Ikarashi, Nishi-ku, Niigata, Niigata 950-2181, Japan.
authors.forename: Tomomi
authors.initials: T
authors.lastname: Hasegawa
authors.affiliation: Department of Biology, Faculty of Science, Niigata University, Ikarashi, Nishi-ku, Niigata, Niigata 950-2181, Japan.
authors.forename: Rieko
authors.initials: R
authors.lastname: Okada
authors.affiliation: Graduate School of Science and Technology, Niigata University, Ikarashi, Nishi-ku, Niigata, Niigata 950-2181, Japan; Department of Biology, Faculty of Science, Niigata University, Ikarashi, Nishi-ku, Niigata, Niigata 950-2181, Japan. Electronic address: wada-403@qj9.so-net.ne.jp.
authors.forename: Kiyotoshi
authors.initials: K
authors.lastname: Takeno
mesh_terms: D000598:Amino Acids, Cyclic / Q000378:metabolism; D000625:Aminooxyacetic Acid / Q000494:pharmacology*; D018548:Cotyledon / Q000187:drug effects / Q000201:enzymology / Q000502:physiology; D035264:Flowers / Q000187:drug effects / Q000201:enzymology / Q000502:physiology; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D007210:Indoleacetic Acids / Q000378:metabolism; D049915:Ipomoea nil / Q000187:drug effects / Q000201:enzymology / Q000502:physiology*; D053858:Metabolic Networks and Pathways / Q000187:drug effects; D010650:Phenylalanine Ammonia-Lyase / Q000037:antagonists & inhibitors* / Q000378:metabolism; D010937:Plant Growth Regulators / Q000378:metabolism*; D010940:Plant Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism; D011073:Polyamines / Q000378:metabolism; D011700:Putrescine / Q000378:metabolism; D020156:Salicylic Acid / Q000378:metabolism; D013312:Stress, Physiological
chemical_list: D000598:Amino Acids, Cyclic; D007210:Indoleacetic Acids; D010937:Plant Growth Regulators; D010940:Plant Proteins; D011073:Polyamines; D000625:Aminooxyacetic Acid; C023863:1-aminocyclopropane-1-carboxylic acid; C030737:indoleacetic acid; D010650:Phenylalanine Ammonia-Lyase; D020156:Salicylic Acid; D011700:Putrescine
keywords: Indole-3-acetic acid; Phenylalanine ammonia-lyase; Polyamine; Salicylic acid; Stress-induced flowering