Plant Molecular Biology

, Volume 37, Issue 6, pp 897–910 | Cite as

Eucalyptus has a functional equivalent of the Arabidopsis floral meristem identity gene LEAFY

  • Simon G. Southerton
  • Steven H. Strauss
  • Mark R. Olive
  • Rebecca L. Harcourt
  • Veronique Decroocq
  • Xiaomei Zhu
  • Danny J. Llewellyn
  • W. James Peacock
  • Elizabeth S. Dennis


Two genes cloned from Eucalyptus globulus, Eucalyptus LeaFy (ELF1 and ELF2), have sequence homology to the floral meristem identity genes LEAFY from Arabidopsis and FLORICAULA from Antirrhinum. ELF1 is expressed in the developing eucalypt floral organs in a pattern similar to LEAFY while ELF2 appears to be a pseudo gene. ELF1 is expressed strongly in the early floral primordium and then successively in the primordia of sepals, petals, stamens and carpels. It is also expressed in the leaf primordia and young leaves and adult and juvenile trees.

The ELF1 promoter coupled to a GUS reporter gene directs expression in transgenic Arabidopsis in a temporal and tissue-specific pattern similar to an equivalent Arabidopsis LEAFY promoter construct. Strong expression is seen in young flower buds and then later in sepals and petals. No expression was seen in rosette leaves or roots of flowering plants or in any non-flowering plants grown under long days. Furthermore, ectopic expression of the ELF1 gene in transgenic Arabidopsis causes the premature conversion of shoots into flowers, as does an equivalent 35S-LFY construct. These data suggest that ELF1 plays a similar role to LFY in flower development and that the basic mechanisms involved in flower initiation and development in Eucalyptus are similar to those in Arabidopsis.

Eucalyptus globulus floral meristem identity gene flower development in situ hybridization LEAFY homologue 


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Copyright information

© Kluwer Academic Publishers 1998

Authors and Affiliations

  • Simon G. Southerton
    • 1
  • Steven H. Strauss
    • 2
  • Mark R. Olive
    • 3
  • Rebecca L. Harcourt
    • 4
  • Veronique Decroocq
    • 5
  • Xiaomei Zhu
    • 3
  • Danny J. Llewellyn
    • 3
  • W. James Peacock
    • 3
  • Elizabeth S. Dennis
    • 3
  1. 1.Department of BiochemistryUniversity of QueenslandSt. LuciaAustralia
  2. 2.Department of Forest ScienceOregon State UniversityCorvallisUSA
  3. 3.CSIRO Plant IndustryCanberraAustralia
  4. 4.CSIRO EntomologyCanberra City
  5. 5.INRA Centre de Bordeaux, UREFVVillenave d';OrnonFrance

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