Skip to main content
PMC home page
Plant Physiology logoLink to Plant Physiology
. 1995 Apr;107(4):1075–1082. doi: 10.1104/pp.107.4.1075

Cytokinin action is coupled to ethylene in its effects on the inhibition of root and hypocotyl elongation in Arabidopsis thaliana seedlings.

A J Cary 1, W Liu 1, S H Howell 1
PMCID: PMC157239  PMID: 7770519

Abstract

Cytokinins have profound effects on seedling development in Arabidopsis thaliana. Benzyladenine (BA) inhibits root elongation in light- or dark-grown seedlings, and in dark-grown seedlings BA inhibits hypocotyl elongation and exaggerates the curvature of apical hooks. The latter are characteristic ethylene responses and, therefore, the possible involvement of ethylene in BA responses was examined in seedlings. It was found that the inhibitory effects of BA on root and hypocotyl elongation were partially blocked by the action of ethylene inhibitors or ethylene-resistant mutations (ein1-1 and ein2-1). Ethylene production was stimulated by submicromolar concentrations of BA and could account, in part, for the inhibition of root and hypocotyl elongation. It was demonstrated further that BA did not affect the sensitivity of seedlings to ethylene. Thus, the effect of cytokinin on root and hypocotyl elongation in Arabidopsis appears to be mediated largely by the production of ethylene. The coupling between cytokinin and ethylene responses is further supported by the discovery that the cytokinin-resistant mutant ckr1 is resistant to ethylene and is allelic to the ethylene-resistant mutant ein2.

Full Text

The Full Text of this article is available as a PDF (1.3 MB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Aharoni N., Anderson J. D., Lieberman M. Production and action of ethylene in senescing leaf discs: effect of indoleacetic Acid, kinetin, silver ion, and carbon dioxide. Plant Physiol. 1979 Nov;64(5):805–809. doi: 10.1104/pp.64.5.805. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Beyer E. M. Effect of silver ion, carbon dioxide, and oxygen on ethylene action and metabolism. Plant Physiol. 1979 Jan;63(1):169–173. doi: 10.1104/pp.63.1.169. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Chory J., Reinecke D., Sim S., Washburn T., Brenner M. A Role for Cytokinins in De-Etiolation in Arabidopsis (det Mutants Have an Altered Response to Cytokinins). Plant Physiol. 1994 Feb;104(2):339–347. doi: 10.1104/pp.104.2.339. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Fuchs Y., Lieberman M. Effects of Kinetin, IAA, and Gibberellin on Ethylene Production, and Their Interactions in Growth of Seedlings. Plant Physiol. 1968 Dec;43(12):2029–2036. doi: 10.1104/pp.43.12.2029. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Kang B. G., Yocum C. S., Burg S. P., Ray P. M. Ethylene and carbon dioxide: mediation of hypocotyl hook-opening response. Science. 1967 May 19;156(3777):958–959. doi: 10.1126/science.156.3777.958. [DOI] [PubMed] [Google Scholar]
  6. Kao C. H., Yang S. F. Role of ethylene in the senescence of detached rice leaves. Plant Physiol. 1983 Dec;73(4):881–885. doi: 10.1104/pp.73.4.881. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Kieber J. J., Ecker J. R. Ethylene gas: it's not just for ripening any more! Trends Genet. 1993 Oct;9(10):356–362. doi: 10.1016/0168-9525(93)90041-f. [DOI] [PubMed] [Google Scholar]
  8. Konieczny A., Ausubel F. M. A procedure for mapping Arabidopsis mutations using co-dominant ecotype-specific PCR-based markers. Plant J. 1993 Aug;4(2):403–410. doi: 10.1046/j.1365-313x.1993.04020403.x. [DOI] [PubMed] [Google Scholar]
  9. Lee K. H., Larue T. A. Exogenous Ethylene Inhibits Nodulation of Pisum sativum L. cv Sparkle. Plant Physiol. 1992 Dec;100(4):1759–1763. doi: 10.1104/pp.100.4.1759. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Lincoln C., Britton J. H., Estelle M. Growth and development of the axr1 mutants of Arabidopsis. Plant Cell. 1990 Nov;2(11):1071–1080. doi: 10.1105/tpc.2.11.1071. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Medford J. I., Horgan R., El-Sawi Z., Klee H. J. Alterations of Endogenous Cytokinins in Transgenic Plants Using a Chimeric Isopentenyl Transferase Gene. Plant Cell. 1989 Apr;1(4):403–413. doi: 10.1105/tpc.1.4.403. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Memelink J., Hoge J. H., Schilperoort R. A. Cytokinin stress changes the developmental regulation of several defence-related genes in tobacco. EMBO J. 1987 Dec 1;6(12):3579–3583. doi: 10.1002/j.1460-2075.1987.tb02688.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Romano C. P., Cooper M. L., Klee H. J. Uncoupling Auxin and Ethylene Effects in Transgenic Tobacco and Arabidopsis Plants. Plant Cell. 1993 Feb;5(2):181–189. doi: 10.1105/tpc.5.2.181. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Rose A. B., Casselman A. L., Last R. L. A Phosphoribosylanthranilate Transferase Gene Is Defective in Blue Fluorescent Arabidopsis thaliana Tryptophan Mutants. Plant Physiol. 1992 Oct;100(2):582–592. doi: 10.1104/pp.100.2.582. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Su W., Howell S. H. A Single Genetic Locus, Ckr1, Defines Arabidopsis Mutants in which Root Growth Is Resistant to Low Concentrations of Cytokinin. Plant Physiol. 1992 Aug;99(4):1569–1574. doi: 10.1104/pp.99.4.1569. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Wilson A. K., Pickett F. B., Turner J. C., Estelle M. A dominant mutation in Arabidopsis confers resistance to auxin, ethylene and abscisic acid. Mol Gen Genet. 1990 Jul;222(2-3):377–383. doi: 10.1007/BF00633843. [DOI] [PubMed] [Google Scholar]

Articles from Plant Physiology are provided here courtesy of Oxford University Press

RESOURCES