Evidence for a universal pathway of abscisic acid biosynthesis in higher plants from sup 18 O incorporation patterns

Journal Article · Fri Dec 01 00:00:00 EST 1989 · Plant Physiology; (USA)

DOI:https://doi.org/10.1104/pp.91.4.1594· OSTI ID:5726150

Zeevaart, J A.D.; Heath, T G; Gage, D A ^[1]

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1. Michigan State University, East Lansing (USA)

Previous labeling studies of abscisic acid (ABA) with {sup 18}O{sub 2} have been mainly conducted with water-stressed leaves. In this study, {sup 18}O incorporation into ABA of stressed leaves of various species was compared with {sup 18}O labeling of ABA of turgid leaves and of fruit tissue in different stages of ripening. In stressed leaves of all six species investigated, avocado (Persea americana), barley (Hordeum vulgare), bean (Phaseolus vulgaris), cocklebur (Xanthium strumarium), spinach (Spinacia oleracea), and tobacco (Nicotiana tabacum), {sup 18}O was most abundant in the carboxyl group, whereas incorporation of a second and third {sup 18}O in the oxygen atoms on the ring of ABA was much less prominent after 24 h in {sup 18}O{sub 2}. ABA from turgid bean leaves showed significant {sup 18}O incorporation, again with highest {sup 18}O enrichment in the carboxyl group. On the basis of {sup 18}O-labeling patterns observed in ABA from different tissues it is concluded that, despite variations in precusor pool sizes and intermediate turnover rates, there is a universal pathway of ABA biosynthesis in higher plants which involves cleavage of a larger precursor molecule, presumably an oxygenated carotenoid.

• OSTI ID: 5726150
• Journal Information: Plant Physiology; (USA), Vol. 91:4; ISSN 0032-0889
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
ABSCISIC ACID
BIOSYNTHESIS
AVOCADOS
BARLEY
NICOTIANA
OXYGEN 18
OXYGEN COMPOUNDS
PHASEOLUS
SPINACH
TRACER TECHNIQUES
AUXINS
CARBOXYLIC ACIDS
CEREALS
EVEN-EVEN NUCLEI
FOOD
FRUITS
GRAMINEAE
ISOTOPE APPLICATIONS
ISOTOPES
LEGUMINOSAE
LIGHT NUCLEI
LILIOPSIDA
MAGNOLIOPHYTA
MAGNOLIOPSIDA
MONOCARBOXYLIC ACIDS
NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
OXYGEN ISOTOPES
PLANT GROWTH REGULATORS
PLANTS
STABLE ISOTOPES
SYNTHESIS
VEGETABLES
550201* - Biochemistry- Tracer Techniques