Abstract
[2H, 3H]Gibberellin A4 (GA4) or [2H, 3H] GA9 were applied to the shoot tips of seedlings of elongated internode (ein), a tall mutant of rapid cycling Brassica rapa. Following [2H]GA9 application, [2H]GA51, [2H]GA20 and [2H]GA4 were identified as products by GC-MS, while [2H]GA34 and [2H]GA1 were formed from [2H]GA4. Other isotopically labelled products, including abundant putative conjugates, were also produced, but were not identified. Thus, in B. rapa, GA1 biosynthesis involves the convergence of at least two metabolic pathways; it can be formed via GA4 or GA20, the latter of which can originate from GA9 or from GA19.
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Devlin PF, Rood SB, Somers DE, Quail PH and Whitelam GC (1992) Photophysiology of the elongated internode (ein) mutant of Brassica rapa ein mutant lacks a detectable phytochrome B-like polypeptide. Plant Physiol 100: 1442–1447
Durley RC, Crozier A, Pharis RP and McLaughlin GE (1972) Chromatography of 33 gibberellins on a gradient eluted silica gel partition column. Phytochemistry 11: 3029–3033
Durley RC and Pharis RP (1973) Interconversion of gibberellin A4 to gibberellins A1 and A34 by dwarf rice, cultivar Tanginbozu. Planta 109: 357–361
Durley RC, Pharis RP and Zeevaart JAD (1975) Metabolism of [3H] gibberellin A20 by plants of Bryophyllum diagremontianum under long- and short-day conditions. Planta 126: 139–149
Gaskin P, MacMillan J, Firn RD and Pryce RJ (1971) “Parafilm”: A convenient source of n-alkane standards for the determination of gas chromatographic retention indices. Phytochemistry 10: 1155–1157
Graebe JE (1987) Gibberellin biosynthesis and control. Ann Rev Plant Physiol 38: 419–465
Hedden P (1987) Gibberellins. In: Rivier L and Crozier A (eds) Principles and Practice of Plant Hormone Analysis, Vol 1, pp 9–110. London: Academic Press
Hedden P, Croker SJ, Rademacher W and Jung J (1989) Effects of the triazole plant growth retardant BAS 111. W on gibberellin levels in oilseed rape, Brassica napus. Physiol Plant 75: 445–451
Ingram TJ, Reid JB, Murfet IC, Gaskin P, Willis CL and MacMillan J (1984) Internode length in Pisum. The le gene controls the 3β-hydroxylation of gibberellin A20 to gibberellin A1. Planta 160: 455–463
Junttila O (1993) Exogenous applied GA4 is converted to GA1 in seedlings of Salix. Physiol Plant 12: 35–39
Junttila O, Jensen E, Pearce DW and Pharis RP (1992) Stimulation of shoot elongation in Salix pentandra by gibberellin A9 — activity appears to be dependent upon hydroxylation to GA1 via GA4. Physiol Plant 84: 13–120
Kobayashi M, Gaskin P, Spray CR, Suzuki Y, Phinney BO and MacMillan J (1993) Metabolism and biological activity of gibberellin A4 in vegetative shoots of Zea mays, Oryza sativa, and Arabidopsis thaliana. Plant Physiol 102: 379–396
Koshioka M, Douglas TJ, Ernst D, Huber J and Pharis RP (1983) Metabolism of [3H]gibberellin A4 in somatic suspension cultures of anise. Phytochemistry 22: 1577–1584
Koshioka M, Harada J, Takeno K, Noma M, Sassa T, Ogiyama K, Taylor JS, Rood SB, Legge RL and Pharis RP (1983) Reversed-phase C18 high-performance liquid chromatography of acidic and conjugated gibberellins. J Chromatogr 256: 101–115
MacMillan J and Pryce RB (1973) The gibberellins. In: Miller LP (ed) Phytochemistry, pp 282–286. New York: Van Rostrand-Reinhold
Mandel R (1992) The hormone physiology of microsporederived embryos of Brassica napus cv. topaz. M.Sc. Thesis, Univ Calgary, Canada
Moritz T, Philipson JJ and Odén PC (1989) Metabolism of tritiated and deuterated gibberellins A1, A4 and A9 in Sitka spruce (Picea sitchensis) shoots during the period of cone-bud differentiation. Physiol Plant 77: 39–45
Phinney BO (1985) Gibberellin A1, dwarfism and shoot elongation in higher plants. Biol Plant 27: 172–179
Railton ID, Durley RC and Pharis RP (1974) Metabolism of tritiated gibberellin A9 by shoots of dark-grown dwarf pea, cv. meteor. Plant Physiol 54: 6–12
Rood SB, Pearce D and Pharis RP (1987) Identification of endogenous gibberellins from oilseed rape. Plant Physiol 85: 605–607
Rood SB, Pearce D, Williams PH and Pharis RP (1989) A gibberellin-deficient Brassica mutant-rosette. Plant Physiol 89: 482–487
Rood SB, Pharis RP and Koshioka M (1983) Reversible conjugation of gibberellins in situ in maize. Plant Physiol 73: 340–346
Rood SB, Williams PH, Pearce D, Murofushi N, Mander LN and Pharis RP (1990) A mutant gene that increases gibberellin production in Brassica. Plant Physiol 93: 1168–1174
Spray CR, Phinney BO, Gaskin P, Gilmour SJ and MacMillan J (1984) Internode length in Zea mays L. The dwarf-1 mutation controls the 3β-hydroxylation of gibberellin A20 to gibberellin A1. Planta 160: 464–468
Takahashi M, Kamiya Y, Takahashi N and Graebe JE (1986) Metabolism of gibberellins in a cell-free system from immature seeds of Phaseolus vulgaris L. Planta 168: 190–199
Yamane H, Murofushi N, Osada H and Takahashi N (1977) Metabolism of gibberellins in early immature bean seeds. Phytochemistry 16: 831–835
Zanewich K and Rood S (1993) Distribution of endogenous gibberellins in vegetative and reproductive organs of Brassica. J Plant Growth Regul 12: 41–46
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Rood, S., Hedden, P. Convergent pathways of gibberellin A1 biosynthesis in Brassica . Plant Growth Regul 15, 241–246 (1994). https://doi.org/10.1007/BF00029897
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DOI: https://doi.org/10.1007/BF00029897