Abstract
[17-13C,3H]Gibberellin A4 (GA4) was injected into the shoots of tall (W23/L317), dwarf-1 (d1), and dwarf-5 (d5) Zea mays L. (maize); tall (cv Nipponbare), dwarf-x (dx), and dwarf-y (dy) Oryza sativa L. (rice); and tall (ecotype Landsberg erecta), ga4, and ga5 Arabidopsis thaliana (L.) Heynh. [13C]GA4 and its metabolites were identified from the shoots by full-scan gas chromatography-mass spectrometry and Kovats retention indices. GA4 was metabolized to GA1 in all nine genotypes. GA4 was also metabolized in some of the genotypes to 3-epi-GA1, GA2, 2[beta]-OH-GA2, 3-epi-GA2, endo-GA4, 16[alpha], 17-H2-16, 17-(OH)2-GA4, GA34, endo-GA34, GA58, 15-epi-GA63, GA71, and 16-epi-GA82. No evidence was found for the metabolism of GA4 to GA7 or of GA4 to GA3. The bioactivities of GA4 and GA1 were determined using the six dwarf mutants for assay. GA4 and GA1 had similar activities for the maize and rice mutants. For the Arabidopsis mutants, GA4 was more active than GA1 at low dosages; GA4 was less active than GA1 at higher dosages.
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Selected References
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- Fujioka S., Yamane H., Spray C. R., Phinney B. O., Gaskin P., Macmillan J., Takahashi N. Gibberellin A(3) Is Biosynthesized from Gibberellin A(20) via Gibberellin A(5) in Shoots of Zea mays L. Plant Physiol. 1990 Sep;94(1):127–131. doi: 10.1104/pp.94.1.127. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Rood S. B., Pharis R. P., Koshioka M. Reversible conjugation of gibberellins in situ in maize. Plant Physiol. 1983 Oct;73(2):340–346. doi: 10.1104/pp.73.2.340. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Talon M., Koornneef M., Zeevaart J. A. Endogenous gibberellins in Arabidopsis thaliana and possible steps blocked in the biosynthetic pathways of the semidwarf ga4 and ga5 mutants. Proc Natl Acad Sci U S A. 1990 Oct;87(20):7983–7987. doi: 10.1073/pnas.87.20.7983. [DOI] [PMC free article] [PubMed] [Google Scholar]