Plant Molecular Biology

, Volume 32, Issue 6, pp 1067–1074

The petunia homologue of tomato gast1: transcript accumulation coincides with gibberellin-induced corolla cell elongation

Authors

  • Gili Ben-Nissan
    • The Kennedy-Leigh Centre for Horticultural ResearchThe Hebrew University of Jerusalem
  • David Weiss
    • The Kennedy-Leigh Centre for Horticultural ResearchThe Hebrew University of Jerusalem
Research Article

DOI: 10.1007/BF00041390

Cite this article as:
Ben-Nissan, G. & Weiss, D. Plant Mol Biol (1996) 32: 1067. doi:10.1007/BF00041390

Abstract

Gibberellins (GAs) regulate petunia corolla pigmentation and elongation. To study this hormone's effect at the molecular level, we used the tomato gast1 gene as a probe to isolate a gibberellin-induced gene (gip) from petunia corollas. The deduced sequence of gip exhibited 82% identity with GAST1 protein and contained a short, highly hydrophobic N-terminal region. High levels of gip expression were detected in elongating corollas and young stem internodes. When detached corollas were grown in vitro in sucrose medium, gip expression was strongly induced by gibberellic acid (GA3). GA3-induced gip expression in corollas was inhibited by abscisic acid (ABA). The expression of the gene was also induced by GA3 in detached young stem segments. Sucrose was not essential for GA-induced gip expression in corollas but enhanced its effect. In stems, on the other hand, sucrose inhibited the effect of the hormone. The results of the present work support the possible role of gip in GA-induced corolla and stem elongation.

Key words

corolla elongationgibberellic acidplant hormonesPetunia hybridastem elongation

Copyright information

© Kluwer Academic Publishers 1996