Skip to main content
NCBI home page
Plant Physiology logoLink to Plant Physiology
. 1997 Aug;114(4):1471–1476. doi: 10.1104/pp.114.4.1471

Gibberellins and stem growth in Arabidopsis thaliana. Effects of photoperiod on expression of the GA4 and GA5 loci.

Y L Xu 1, D A Gage 1, J A Zeevaart 1
PMCID: PMC158440  PMID: 9276956

Abstract

Arabidopsis thaliana (L.) Heynh. is a quantitative long-day (LD) rosette plant in which stem growth is mediated by gibberellins (CAs). Application of GAs to plants in short-day (SD) conditions resulted in rapid stem elongation and flower formation, with GA4 and GA9 being equally effective, and GA1 showing lower activity. The effects of photoperiod on the levels of endogenous GAs were measured by combined gas chromatography-mass spectrometry with selected ion monitoring. When plants were transferred from SD to LD conditions there was a slight decrease in the level of GA53 and an increase in the levels of C19-GAs, GA9, GA20, GA1, and GA8, indicating that GA 20-oxidase activity is stimulated in LD conditions. Expression of GA5, which encodes GA 20-oxidase, was highest in elongating stems and was correlated with the rate of stem elongation. By contrast, GA4, which encodes 3 beta-hydroxylase, showed low expression in stems and its expression was not correlated with the rate of stem elongation. We conclude that stem elongation in LD conditions is at least in part due to increased expression of GA5, whereas expression of GA4 is not under photoperiodic control.

Full Text

The Full Text of this article is available as a PDF (613.2 KB).

Selected References

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

  1. Chiang H. H., Hwang I., Goodman H. M. Isolation of the Arabidopsis GA4 locus. Plant Cell. 1995 Feb;7(2):195–201. doi: 10.1105/tpc.7.2.195. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Gilmour S. J., Bleecker A. B., Zeevaart J. A. Partial purification of gibberellin oxidases from spinach leaves. Plant Physiol. 1987 Sep;85(1):87–90. doi: 10.1104/pp.85.1.87. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Gilmour S. J., Zeevaart J. A., Schwenen L., Graebe J. E. Gibberellin metabolism in cell-free extracts from spinach leaves in relation to photoperiod. Plant Physiol. 1986 Sep;82(1):190–195. doi: 10.1104/pp.82.1.190. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Phillips A. L., Ward D. A., Uknes S., Appleford N. E., Lange T., Huttly A. K., Gaskin P., Graebe J. E., Hedden P. Isolation and expression of three gibberellin 20-oxidase cDNA clones from Arabidopsis. Plant Physiol. 1995 Jul;108(3):1049–1057. doi: 10.1104/pp.108.3.1049. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Sponsel V. M., Ross J. J., Reynolds M. R., Symons G. M., Reid J. B. The Gibberellin Status of lip1, a Mutant of Pea That Exhibits Light-Independent Photomorphogenesis. Plant Physiol. 1996 Sep;112(1):61–66. doi: 10.1104/pp.112.1.61. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Sun T. P., Kamiya Y. The Arabidopsis GA1 locus encodes the cyclase ent-kaurene synthetase A of gibberellin biosynthesis. Plant Cell. 1994 Oct;6(10):1509–1518. doi: 10.1105/tpc.6.10.1509. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Talon M., Koornneef M., Zeevaart J. A. Endogenous gibberellins in Arabidopsis thaliana and possible steps blocked in the biosynthetic pathways of the semidwarf ga4 and ga5 mutants. Proc Natl Acad Sci U S A. 1990 Oct;87(20):7983–7987. doi: 10.1073/pnas.87.20.7983. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Talon M., Zeevaart J. A., Gage D. A. Identification of Gibberellins in Spinach and Effects of Light and Darkness on their Levels. Plant Physiol. 1991 Dec;97(4):1521–1526. doi: 10.1104/pp.97.4.1521. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Wu K., Li L., Gage D. A., Zeevaart J. A. Molecular cloning and photoperiod-regulated expression of gibberellin 20-oxidase from the long-day plant spinach. Plant Physiol. 1996 Feb;110(2):547–554. doi: 10.1104/pp.110.2.547. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Xu Y. L., Li L., Wu K., Peeters A. J., Gage D. A., Zeevaart J. A. The GA5 locus of Arabidopsis thaliana encodes a multifunctional gibberellin 20-oxidase: molecular cloning and functional expression. Proc Natl Acad Sci U S A. 1995 Jul 3;92(14):6640–6644. doi: 10.1073/pnas.92.14.6640. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Yamaguchi S., Saito T., Abe H., Yamane H., Murofushi N., Kamiya Y. Molecular cloning and characterization of a cDNA encoding the gibberellin biosynthetic enzyme ent-kaurene synthase B from pumpkin (Cucurbita maxima L.). Plant J. 1996 Aug;10(2):203–213. doi: 10.1046/j.1365-313x.1996.10020203.x. [DOI] [PubMed] [Google Scholar]
  12. Zeevaart J. A. Effects of photoperiod on growth rate and endogenous gibberellins in the long-day rosette plant spinach. Plant Physiol. 1971 Jun;47(6):821–827. doi: 10.1104/pp.47.6.821. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Zeevaart J. A., Gage D. A., Talon M. Gibberellin A1 is required for stem elongation in spinach. Proc Natl Acad Sci U S A. 1993 Aug 1;90(15):7401–7405. doi: 10.1073/pnas.90.15.7401. [DOI] [PMC free article] [PubMed] [Google Scholar]

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

RESOURCES