Plant Physiol. Drug Metab Dispos
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Plant Physiology 50:702-705 (1972)
© 1972 American Society of Plant Biologists

This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via CrossRef
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Schmitz, R. Y.
Right arrow Articles by Leonard, N. J.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Schmitz, R. Y.
Right arrow Articles by Leonard, N. J.
Agricola
Right arrow Articles by Schmitz, R. Y.
Right arrow Articles by Leonard, N. J.
Articles

Cytokinins: Synthesis and Biological Activity of Geometric and Position Isomers of Zeatin 1

Ruth Y. Schmitza and Folke Skooga

Anthony J. Playtisb and Nelson J. Leonardb

a Institute of Plant Development, Birge Hall, University of Wisconsin, Madison, Wisconsin 53706, b School of Chemical Sciences, University of Illinois, Urbana, Illinois 61801

Geometric and position isomers of zeatin and of ribosylzeatin and other compounds closely related to zeatin have been tested in the tobacco (Nicotiana tabacum var. Wisconsin No. 38) bioassay. None was more active than zeatin itself. There was a much greater difference in activity (> 50-fold) between trans- and cis-zeatin than between trans-isozeatin [6-(4-hydroxy-2-methyl-trans-2-butenylamino) purine] and cis-isozeatin [6-(4-hydroxy-2-methyl-cis-2-butenylamino) purine], the latter being less active than cis-zeatin and trans-isozeatin. Higher concentrations were required for equivalent callus growth stimulated by the 9-ribosyl derivatives, which followed an order of decreasing activity: ribosyl-trans-zeatin > ribosyl-cis-zeatin > ribosyl-trans-isozeatin > ribosyl-cis-isozeatin, corresponding roughly to that of the bases. The effect of side chain, double bond saturation was to diminish the activity, and in the dihydro series the shift of the methyl group from the 3- to the 2-position in going from dihydrozeatin to dihydroisozeatin [6-(4-hydroxy-2-methylbutylamino) purine] resulted in a 70-fold decrease in activity. cis-Norzeatin [6-(4-hydroxy-cis-2-butenylamino) purine], which was less than one-fifth as active as cis-zeatin, showed the effect of complete removal of the side chain methyl group, and cyclic-norzeatin [6-(3,6-dihydro-1,2-oxazin-2-yl) purine] was about 1/100 as active as cis-norzeatin. These findings delineate completely the effect on the cytokinin activity of zeatin of variation in side chain geometry, presence and position of the methyl substituent, presence and geometry of hydroxyl substitution, presence of the double bond, and of side chain cyclization.

1 This work was supported at the University of Wisconsin by National Science Foundation Research Grant GB-25812 and by the Research Committee of the Graduate School with funds from the Wisconsin Alumni Research Foundation. Supported at the University of Illinois by National Institutes of Health Research Grant GM-05829. A. J. P. held the Eli Lilly and Company Fellowship at the University of Illinois during 1970 to 1971.




This article has been cited by other articles:


Home page
 Proc. Natl. Acad. Sci. USAHome page
H. Sakakibara, H. Kasahara, N. Ueda, M. Kojima, K. Takei, S. Hishiyama, T. Asami, K. Okada, Y. Kamiya, T. Yamaya, et al.
Agrobacterium tumefaciens increases cytokinin production in plastids by modifying the biosynthetic pathway in the host plant
PNAS, July 12, 2005; 102(28): 9972 - 9977.
[Abstract] [Full Text] [PDF]

Home page
 Plant Physiol.Home page
M. C. Mok, R. C. Martin, P. I. Dobrev, R. Vankova, P. S. Ho, K. Yonekura-Sakakibara, H. Sakakibara, and D. W.S. Mok
Topolins and Hydroxylated Thidiazuron Derivatives Are Substrates of Cytokinin O-Glucosyltransferase with Position Specificity Related to Receptor Recognition
Plant Physiology, March 1, 2005; 137(3): 1057 - 1066.
[Abstract] [Full Text] [PDF]

Home page
 J. Biol. Chem.Home page
K. Takei, T. Yamaya, and H. Sakakibara
Arabidopsis CYP735A1 and CYP735A2 Encode Cytokinin Hydroxylases That Catalyze the Biosynthesis of trans-Zeatin
J. Biol. Chem., October 1, 2004; 279(40): 41866 - 41872.
[Abstract] [Full Text] [PDF]

Home page
 Plant Physiol.Home page
K. Yonekura-Sakakibara, M. Kojima, T. Yamaya, and H. Sakakibara
Molecular Characterization of Cytokinin-Responsive Histidine Kinases in Maize. Differential Ligand Preferences and Response to cis-Zeatin
Plant Physiology, April 1, 2004; 134(4): 1654 - 1661.
[Abstract] [Full Text] [PDF]

Home page
 Plant Physiol.Home page
Y. K. Veach, R. C. Martin, D. W.S. Mok, J. Malbeck, R. Vankova, and M. C. Mok
O-Glucosylation of cis-Zeatin in Maize. Characterization of Genes, Enzymes, and Endogenous Cytokinins
Plant Physiology, March 1, 2003; 131(3): 1374 - 1380.
[Abstract] [Full Text] [PDF]

Home page
 Proc. Natl. Acad. Sci. USAHome page
R. C. Martin, M. C. Mok, J. E. Habben, and D. W. S. Mok
A maize cytokinin gene encoding an O-glucosyltransferase specific to cis-zeatin
PNAS, May 8, 2001; 98(10): 5922 - 5926.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
ASPB Publications PLANT PHYSIOLOGY® THE PLANT CELL
Copyright © 1972 by the American Society of Plant Biologists