ISSN:
1432-2048
Keywords:
Agrobacterium
;
Auxin in tumors
;
Cytokinin (in tumors, turnover, oxidase)
;
Mutant (T-DNA)
;
Nicotiana (crown gall)
;
T-DNA mutants
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract The levels of the major cytokinins, zeatin, zeatin riboside, zeatin riboside-5′-monophosphate and zeatin-7-glucoside were measured in tobacco (Nicotiana tabacum L.) crown-gall tissues carrying insertion and deletion mutations in the T-DNA. Measurements were made by combined gas chromatography-mass spectrometry using selected ion monitoring with 15N- and 2H-labelled internal standards. The results demonstrate that, relative to wild-type tumour tissue, cytokinin levels are considerably elevated in tissues lacking functional T-DNA auxin-biosynthetic genes. From a detailed analysis of the major cytokinin metabolites it is concluded that a reduction in the extent of cytokinin degradation via N6-side-chain cleavage is an important factor leading to increased cytokinin levels in these tissues.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00392449
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