Patterning of inflorescences and flowers by the F-Box protein DOUBLE TOP and the LEAFY homolog ABERRANT LEAF AND FLOWER of petunia

Plant Cell. 2008 Aug;20(8):2033-48. doi: 10.1105/tpc.108.060871. Epub 2008 Aug 19.


Angiosperms display a wide variety of inflorescence architectures differing in the positions where flowers or branches arise. The expression of floral meristem identity (FMI) genes determines when and where flowers are formed. In Arabidopsis thaliana, this is regulated via transcription of LEAFY (LFY), which encodes a transcription factor that promotes FMI. We found that this is regulated in petunia (Petunia hybrida) via transcription of a distinct gene, DOUBLE TOP (DOT), a homolog of UNUSUAL FLORAL ORGANS (UFO) from Arabidopsis. Mutation of DOT or its tomato (Solanum lycopersicum) homolog ANANTHA abolishes FMI. Ubiquitous expression of DOT or UFO in petunia causes very early flowering and transforms the inflorescence into a solitary flower and leaves into petals. Ectopic expression of DOT or UFO together with LFY or its homolog ABERRANT LEAF AND FLOWER (ALF) in petunia seedlings activates genes required for identity or outgrowth of organ primordia. DOT interacts physically with ALF, suggesting that it activates ALF by a posttranslational mechanism. Our findings suggest a wider role than previously thought for DOT and UFO in the patterning of flowers and indicate that the different roles of LFY and UFO homologs in the spatiotemporal control of floral identity in distinct species result from their divergent expression patterns.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis Proteins / genetics*
  • Arabidopsis Proteins / metabolism
  • Arabidopsis Proteins / physiology
  • F-Box Proteins / metabolism
  • Flowers / genetics*
  • Flowers / growth & development
  • Flowers / ultrastructure
  • Gene Expression Regulation, Developmental
  • Gene Expression Regulation, Plant
  • Meristem / genetics
  • Meristem / growth & development
  • Meristem / ultrastructure
  • Microscopy, Confocal
  • Microscopy, Electron, Scanning
  • Molecular Sequence Data
  • Plant Proteins / genetics*
  • Plant Proteins / metabolism
  • Plant Proteins / physiology
  • Plants, Genetically Modified / genetics
  • Plants, Genetically Modified / growth & development
  • Plants, Genetically Modified / ultrastructure
  • Protein Binding
  • Transcription Factors / genetics*
  • Transcription Factors / metabolism
  • Transcription Factors / physiology
  • Two-Hybrid System Techniques


  • Arabidopsis Proteins
  • F-Box Proteins
  • LFY protein, Arabidopsis
  • Plant Proteins
  • Transcription Factors
  • UFO protein, Arabidopsis

Associated data

  • GENBANK/AF004843
  • GENBANK/EU352681
  • GENBANK/EU352682
  • GENBANK/EU352683
  • GENBANK/EU352684
  • GENBANK/EU352685
  • GENBANK/EU352686
  • GENBANK/EU849138
  • GENBANK/NM102834
  • GENBANK/NP010615
  • GENBANK/NP563864
  • GENBANK/NP564105
  • GENBANK/NP565123
  • GENBANK/NP565295
  • GENBANK/NP565296
  • GENBANK/NP565297
  • GENBANK/NP565467
  • GENBANK/NP565604
  • GENBANK/NP566692
  • GENBANK/NP566693
  • GENBANK/NP566694
  • GENBANK/NP566695
  • GENBANK/NP566773
  • GENBANK/NP566978
  • GENBANK/NP567090
  • GENBANK/NP567091
  • GENBANK/NP567959
  • GENBANK/NP567967
  • GENBANK/NP568603
  • GENBANK/S71192