title: Combinatorial activities of SHORT VEGETATIVE PHASE and FLOWERING LOCUS C define distinct modes of flowering regulation in Arabidopsis.
abstract: BACKGROUND
  The initiation of flowering is an important developmental transition as it marks the beginning of the reproductive phase in plants. The MADS-box transcription factors (TFs) FLOWERING LOCUS C (FLC) and SHORT VEGETATIVE PHASE (SVP) form a complex to repress the expression of genes that initiate flowering in Arabidopsis. Both TFs play a central role in the regulatory network by conferring seasonal patterns of flowering. However, their interdependence and biological relevance when acting as a complex have not been extensively studied.
  
  
  RESULTS
  We characterized the effects of both TFs individually and as a complex on flowering initiation using transcriptome profiling and DNA-binding occupancy. We find four major clusters regulating transcriptional responses, and that DNA binding scenarios are highly affected by the presence of the cognate partner. Remarkably, we identify genes whose regulation depends exclusively on simultaneous action of both proteins, thus distinguishing between the specificity of the SVP:FLC complex and that of each TF acting individually. The downstream targets of the SVP:FLC complex include a higher proportion of genes regulating floral induction, whereas those bound by either TF independently are biased towards floral development. Many genes involved in gibberellin-related processes are bound by the SVP:FLC complex, suggesting that direct regulation of gibberellin metabolism by FLC and SVP contributes to their effects on flowering.
  
  
  CONCLUSIONS
  The regulatory codes controlled by SVP and FLC were deciphered at the genome-wide level revealing substantial flexibility based on dependent and independent DNA binding that may contribute to variation and robustness in the regulation of flowering.
authors: Julieta L
authors: JL
authors: Mateos
authors: Pedro
authors: P
authors: Madrigal
authors: Kenichi
authors: K
authors: Tsuda
authors: Vimal
authors: V
authors: Rawat
authors: René
authors: R
authors: Richter
authors: Maida
authors: M
authors: Romera-Branchat
authors: Fabio
authors: F
authors: Fornara
authors: Korbinian
authors: K
authors: Schneeberger
authors: Paweł
authors: P
authors: Krajewski
authors: George
authors: G
authors: Coupland
mesh_terms: D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D001665:Binding Sites; D005075:Biological Evolution; D047369:Chromatin Immunoprecipitation; D035264:Flowers / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D053263:Gene Regulatory Networks / Q000187:drug effects; D017343:Genes, Plant; D005838:Genotype; D005875:Gibberellins / Q000494:pharmacology; D026161:MADS Domain Proteins / Q000235:genetics / Q000378:metabolism*; D018519:Meristem / Q000187:drug effects / Q000235:genetics; D008969:Molecular Sequence Data; D018515:Plant Leaves / Q000187:drug effects / Q000235:genetics; D025341:Principal Component Analysis; D011485:Protein Binding / Q000187:drug effects; D012045:Regulatory Sequences, Nucleic Acid / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic / Q000187:drug effects
chemical_list: D029681:Arabidopsis Proteins; C418902:At5g10140 protein, Arabidopsis; D005875:Gibberellins; D026161:MADS Domain Proteins; C407549:SVP protein, Arabidopsis; D014157:Transcription Factors