Abstract
Dominant late-flowering mutant fwa is an epigenetic mutant that ectopically expresses FWA due to promoter hypomethylation. To gain clues to the molecular basis of late-flowering phenotype in fwa, we performed microarray analysis using fwa epiallele and 35S::FWA. The transcription profile suggests that late-flowering phenotype of fwa is not due to the mis-regulation of transcription. Yeast two-hybrid analysis and in vitro pull-down assay showed that FWA protein can specifically interact with FT protein. These results suggest that ectopically-expressed FWA inhibits floral transition by interfering with the FT function through protein interaction. fwa-101D had no effect on the precocious-flowering phenotype of 35S::TSF, 35S::CiFT, and 35S::Hd3a. Therefore, effect of FWA protein seems very specific to FT. No interaction was observed between FWA protein and TSF protein. Specific interaction of FWA with FT enabled us to analyze FT protein function through specific inhibition.
