Identification of SHORT VEGETATIVE PHASE putative targets through whole-genome expression analysis

SVP is a key MADS-box transcription factor for Arabidopsis development since it acts both during vegetative and reproductive phases where it plays different roles probably by interacting with different partners to regulate specific sets of target genes. In fact, whereas SVP functions as a repressor of floral transition during the vegetative phase, it works as floral meristem gene during reproductive phase. We studied the behavior of SVP during two distinct developmental phases: the vegetative and reproductive phase. The aim of these studies is to identify subsets of genes that are regulated by SVP by means of Arabidopsis Tiling 1.0R Arrays (Affymetrix) during the two distinct phases of development. Arabidopsis thaliana seedlings and inflorescences were selected at successive stages of early development for RNA extraction and hybridization on Affymetrix microarrays. To evaluate the amount of SVP expression in the vegetative phase we used svp-41 single mutant and wild-type seedlings grown for 2 weeks in Short Day (SD) conditions (8 h light/16 h dark); for the reproductive phase we used wild-type and svp-41 agl24-2 ap1-12 triple mutant inflorescences grown for 2 weeks in SD conditions and then moved in (LD) conditions (16 h light/16 h dark). The inflorescences were collected at 2 weeks after bolting.