Abstract
Hd3a and FT proteins have been recently proposed to act as florigens in rice and Arabidopsis, respectively. However, molecular mechanisms of their function remain to be determined. In this study, we identified GF14c (14-3-3 isoform protein) as an Hd3a interacting protein in yeast two-hybrid screen. In vitro and in vivo experiments, using a combination of pull-down assay, co-immunoprecipitation and bimolecular fluorescence complementation, confirmed the interaction between Hd3a and GF14c.
Functional analysis using either GF14c overexpression or knockout transgenic rice plants indicated that GF14c plays a role in regulation of flowering. GF14c-overexpressing plants exhibited a delay in flowering and the knockout mutants displayed early flowering that was comparable to wild-type plants under short-day conditions. Taken together, these results suggest that GF14c acts as a negative regulator of flowering by interacting with Hd3a.
