View the Current Issue

Article

  • The EMBO Journal (2003) 22, 3142 - 3152
  • doi:10.1093/emboj/cdg305

Autoregulation of FCA pre-mRNA processing controls Arabidopsis flowering time

Victor Quesada2, Richard Macknight3, Caroline Dean1 and Gordon G. Simpson4

  1. Department of Cell and Developmental Biology, John Innes Centre, Norwich NR4 7UH, UK
  2. Present address: Division de Genetica, Departamento de Biologia Aplicada, Universidad Miguel Hernandez, Campus de Elche, Edificio Vinalopo, 03202 Elche, Alicante, Spain
  3. Present address: Department of Biochemistry, University of Otago, PO Box 56, Dunedin, New Zealand
  4. Present address: Gene Expression Programme, Scottish Crop Research Institute, Invergowrie, Dundee DD2 5DA, UK

Correspondence to:

Gordon G. Simpson, E-mail: gordon.simpson@scri.sari.ac.uk

Received 11 September 2002; Accepted 28 April 2003; Revised 16 April 2003

The timing of the transition to flowering is critical for reproductive success in plants. Arabidopsis FCA encodes an RNA-binding protein that promotes flowering. FCA expression is regulated through alternative processing of its pre-mRNA. We demonstrate here that FCA negatively regulates its own expression by ultimately promoting cleavage and polyadenylation within intron 3. This causes the production of a truncated, inactive transcript at the expense of the full-length FCA mRNA, thus limiting the expression of active FCA protein. We show that this negative autoregulation is under developmental control and requires the FCA WW protein interaction domain. Removal of introns from FCA bypasses the autoregulation, and the resulting increased levels of FCA protein overcomes the repression of flowering normally conferred through the up-regulation of FLC by active FRI alleles. The negative autoregulation of FCA may therefore have evolved to limit FCA activity and hence control flowering time.

  • Keywords:

    • Arabidopsis,
    • autoregulation,
    • FCA,
    • flowering,
    • polyadenylation