eCite Digital Repository

Further evidence for feedback regulation of gibberellin biosynthesis in pea


Ross, JJ and Mackenzie-Hose, AK and Davies, PJ and Lester, DR and Twitchin, B and Reid, JB, Further evidence for feedback regulation of gibberellin biosynthesis in pea, Physiologia Plantarum, 105, (3) pp. 532-538. ISSN 0031-9317 (1999) [Refereed Article]

DOI: doi:10.1034/j.1399-3054.1999.105319.x


In shoots of the garden pea (Pisum sativum L.), the main bioactive gibberellin (GA) is GA 1, which is synthesised from GA 20 by 3β-hydroxylation. Gibberellin A 20 is produced from GA 19, as part of the process known as GA 20-oxidation. Because these steps are thought to be negatively regulated by GA 1, we compared the metabolism of labelled GA 19 and GA 20 in mutants deficient in GA 1, with that observed in isogenic wild-type (WT) plants. There was a large and specific increase in the 3β-hydroxylation of labelled GA 20 in the GA 1-deficient (dwarf) mutants, compared with the WT. Metabolism experiments did not provide convincing evidence for feedback regulation of 20-oxidation, possibly because GA 19 appears to be metabolised rapidly, even in WT pea shoots. Both 3β-hydroxylase and 20-oxidase transcript levels were markedly higher in the mutants than in isogenic WT lines. The results support previous suggestions that both biosynthetic steps are feedback-regulated by GA 1 in pea.

Item Details

Item Type:Refereed Article
Research Division:Biological Sciences
Research Group:Plant biology
Research Field:Plant physiology
Objective Division:Expanding Knowledge
Objective Group:Expanding knowledge
Objective Field:Expanding knowledge in the environmental sciences
UTAS Author:Ross, JJ (Associate Professor John Ross)
UTAS Author:Mackenzie-Hose, AK (Mr Alasdair Kenneth Mackenzie-Hose)
UTAS Author:Davies, PJ (Dr Davies)
UTAS Author:Lester, DR (Dr Diane Lester)
UTAS Author:Reid, JB (Professor Jim Reid)
ID Code:17560
Year Published:1999
Web of Science® Times Cited:24
Deposited By:Plant Science
Deposited On:1999-08-01
Last Modified:2010-11-08

Repository Staff Only: item control page