Linked Life Data

10758505

Source:http://linkedlifedata.com/resource/pubmed/id/10758505

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2000-6-19
pubmed:abstractText
In shoots of the garden pea, the bioactive gibberellin (GA1) is synthesised from GA20, and the enzyme which catalyses this step (a GA 3-oxidase -- PsGA3ox1) is encoded by Mendel's LE gene. It has been reported previously that decapitation of the shoot (excision of the apical bud) dramatically reduces the conversion of [3H]GA20 to [3H]GA1 in stems, and here we show that endogenous GA1 and PsGA3ox1 transcript levels are similarly reduced. We show also that these effects of decapitation are completely reversed by application of the auxin indole-3-acetic acid (IAA) to the 'stump' of decapitated plants. Gibberellin A20 is also converted to an inactive product, GA29, and this step is catalysed by a GA 2-oxidase, PsGA2ox1. In contrast to PsGA3ox1, PsGA2ox1 transcript levels were increased by decapitation and reduced by IAA application. Decapitation and IAA treatment did not markedly affect the level of GA1 precursors. It is suggested that in intact pea plants, auxin from the apical bud moves into the elongating internodes where it (directly or indirectly) maintains PsGA3ox1 transcript levels and, consequently, GA1 biosynthesis.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0960-7412
pubmed:author
pubmed:issnType
Print
pubmed:volume
21
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
547-52
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Evidence that auxin promotes gibberellin A1 biosynthesis in pea.
pubmed:affiliation
School of Plant Science, University of Tasmania, GPO Box 252-55, Hobart, Tasmania 7001, Australia. John.Ross@utas.edu.au
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't