Plant Molecular Biology

, Volume 44, Issue 1, pp 85–90 | Cite as

Glucose repression of α-amylase in barley embryos is independent of GAMYB transcription

  • Elena Loreti
  • Chi-aki Matsukura
  • Frank Gubler
  • Amedeo Alpi
  • Junji Yamaguchi
  • Pierdomenico Perata

Abstract

The induction of α-amylase triggered by gibberellic acid in barley embryos is repressed by sugars. We investigated the effects of glucose on the gibberellin signal transduction pathway to localize the site of interaction of the sugar/hormone signalling pathways. Our results indicate that glucose represses gibberellin signalling late along this hormone transduction pathway, downstream of transcription of the gibberellin-modulated transcriptional activator (GAMYB) needed for α-amylase induction. This result suggests either that glucose repression is transduced by a pathway independent of gibberellin signalling or that repression occurs at the level of GAMYB translation.

α-amylase barley (Hordeum vulgare L.) GAMYB glucose repression 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Bethke, P.C., Schuurink, R. and Jones, R.L. 1997. Hormonal signaling in cereal aleurone. J. Exp. Bot. 48: 1337–1356.Google Scholar
  2. Bethke, P.C. and Jones, R.L. 1999. Gibberellin signaling. Curr. Opin. Plant Biol. 1: 440–446.Google Scholar
  3. Gausing, K. and Barkardottir, R. 1986. Structure and expression of ubiquitin genes in higher plants. Eur. J. Biochem. 158: 57–62.Google Scholar
  4. Gubler, F., Kalla, R., Roberts, J.K. and Jacobsen, J.V. 1995. Gibberellin-regulated expression of a myb gene in barley aleurone cells: evidence for a myb transactivation of a high-pI α-amylase gene promoter. Plant Cell 7: 1879–1891.Google Scholar
  5. Gubler, F., Raventos, D., Keys, M., Watts, R., Mundy, J. and Jacobsen, J.V. 1999. Target genes and regulatory domains of the GAMYB transcriptional activator in cereal aleurone. Plant J. 17: 1–9.Google Scholar
  6. Jones, R.L. and Varner, J.E. 1967. The bioassay of gibberellins. Planta 72: 53–59.Google Scholar
  7. Kouchi, H. and Hata, S. 1993. Isolation and characterization of a novel nodulin cDNA representing genes expressed at early stages of soybean nodule development. Mol. Gen. Genet. 238: 106–119.Google Scholar
  8. Morita, A., Umemura, T., Kuroyanagi, M., Futsuhara, Y., Perata, P. and Yamaguchi, J. 1998. Functional dissection of a sugarrepressed α-amylase gene (Ramy1A) promoter in rice embryos. FEBS Lett. 423: 81–85.Google Scholar
  9. Mitsui, T. and Itoh, K. 1997. The α-amylase multigene family. Trends Plant Sci. ;2: 255–261.Google Scholar
  10. Ohto, M. Hayashi, K., Isobe, M. and Nakamura, K. 1995. Involvement of Ca2+ signalling in the sugar-inducible expression of genes coding for sporamin and α-amylase of sweet potato. Plant J. 7: 297–307.Google Scholar
  11. Penson, S.P., Schuurink, R.C., Fath, A., Gubler, F., Jacobsen, J.V. and Jones R.L. 1996. cGMP is required for gibberellic acid-induced gene expression in barley aleurone. Plant Cell 8: 2325–2333Google Scholar
  12. Perata, P., Matsukura, C., Vernieri, P. and Yamaguchi, J. 1997. Sugar repression of a gibberellin-dependent signaling pathway in barley embryos. Plant Cell 9: 2197–2208.Google Scholar
  13. Rogers, J.C. 1985. Two barley α-amylase gene families are regulated differently in aleurone cells. J. Biol. Chem. 260: 3731–3738.Google Scholar
  14. Rook, F., Gerrits, N., Kortstee, A., van Kampen, M., Borrias, M., Weisbeek, P. and Smeekens, S. 1998. Sucrose-specific signalling represses translation of the Arabidopsis ATB2 bZIP transcription factor gene. Plant J. 15: 253–263.Google Scholar
  15. Sheen, J., Zhou Li, H.-T. and Jang, J.-C. 1999. Sugar as signalling molecules. Curr. Opin. Plant Biol. 2: 410–418.Google Scholar
  16. Takeda, S., Mano, S., Ohto, M. and Nakamura, K 1994. Inhibitors of protein phosphatases 1 and 2A block sugar-inducible gene expression in plants. Plant Physiol. 106: 567–574.Google Scholar
  17. Toyofuku, K., Umemura, T. and Yamaguchi, J. 1998. Promoter elements required for sugar-repression of the Ramy3D gene for α-amylase in rice. FEBS Lett. 428: 275–280.Google Scholar
  18. Toyofuku, K., Loreti, E., Vernieri, P., Alpi, A., Perata, P. and Yamaguchi, J. 2000. Glucose modulates the abscisic acid-inducible Rab 16A gene in cereal embryos. Plant Mol. Biol. 42: 451–460.Google Scholar
  19. Yu, S.-M., Lee, Y.-C., Fang, S.-C., Hwa, S.-F. and Liu L.-F. 1996. Sugars act as signal molecules and osmotica to regulate the expression of α-amylase genes and metabolic activities in germinating cereal grains. Plant Mol. Biol. 30: 1277–1289.Google Scholar

Copyright information

© Kluwer Academic Publishers 2000

Authors and Affiliations

  • Elena Loreti
    • 1
  • Chi-aki Matsukura
    • 2
  • Frank Gubler
    • 3
  • Amedeo Alpi
    • 1
  • Junji Yamaguchi
    • 2
  • Pierdomenico Perata
    • 1
  1. 1.Department of Crop Plant BiologyUniversity of PisaPisaItaly
  2. 2.Nagoya University Bioscience Center, Chikusa, NagoyaNagoyaJapan
  3. 3.CSIRO Plant IndustryCanberra CityAustralia

Personalised recommendations