Journal Article

Combinatorial activities of SHORT VEGETATIVE PHASE and FLOWERING LOCUS C define distinct modes of flowering regulation in Arabidopsis

Madrigal, Pedro, Mateos, Julieta L, Rawat, Vimal, Schneeberger, Korbinian, Romera-Branchat, Maida, Krajewski, Paweł, Fornara, Fabio, Tsuda, Kenichi, Richter, René, Coupland, George

2015

Overview

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. 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. 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.

• Publisher: Springer Nature B.V
• Subject: Arabidopsis / Arabidopsis - drug effects / Arabidopsis - genetics / Arabidopsis - physiology / Arabidopsis Proteins - genetics / Arabidopsis Proteins - metabolism / Base Sequence / Binding Sites / Bioinformatics / Biological Evolution / Chromatin Immunoprecipitation / Deoxyribonucleic acid / DNA / DNA fingerprinting / DNA methylation / Experiments / Flowers & plants / Flowers - drug effects / Flowers - genetics / Flowers - physiology / Gene expression / Gene Expression Profiling / Gene Expression Regulation, Plant - drug effects / Gene regulation / Gene Regulatory Networks - drug effects / Genes, Plant / Genomes / Genomics / Genotype / Gibberellins - pharmacology / MADS Domain Proteins - genetics / MADS Domain Proteins - metabolism / Meristem - drug effects / Meristem - genetics / Molecular Sequence Data / Plant Leaves - drug effects / Plant Leaves - genetics / Principal Component Analysis / Protein Binding - drug effects / Proteins / Regulatory Sequences, Nucleic Acid - genetics / Transcription factors / Transcription Factors - genetics / Transcription Factors - metabolism / Transcription, Genetic - drug effects