Abstract
Dominant late-flowering mutant fwa is an epigenetic mutant that ectopically expresses a GL2-class HD-ZIP gene due to promoter hypomethylation. Genetic analysis suggests that FWA blocks the pathway at and/or downstream of FT. We have shown that FWA protein strongly interacted with FT protein in yeast cells and in vitro. We have also shown that the C-terminal region of FWA is important for interaction with FT, and truncated FWA is unable to delay flowering when over-expressed. We hypothesize that mis-expressed FWA delays flowering by interfering with the interaction between FT and a meristem-specific bZIP transcription factor FD through binding to FT. We are interested in the sites of the plants where FWA can exert its negative effect on flowering. To test this, FWA is being expressed in vascular tissues (including phloem cells which express FT) by vascular-specific promoter or shoot apex by FD promoter. Results of these analyses will be presented.
