Abstract
TWIN SISTER OF FT (TSF) is the closest homolog of FT in the PEBP/RKIP family, suggesting that TSF plays a similar role as a floral promoter. TSF expression was regulated by CO and showed diurnal oscillation. tsf mutation enhanced the late-flowering phenotype of ft. TSF and FT shared similar mode of regulation by FLC, an integrator of autonomous and vernalization pathways. In addition, TSF overexpression caused a precocious flowering phenotype independent of photoperiod, CO and FLC, but dependent of FD. These observations suggest that TSF plays a role as a floral pathway integrator and promotes flowering in a manner similar to FT. Interestingly, TSF and FT expression pattern did not overlap, though both were expressed in the phloem. This finding indicates that the phloem is the site where multiple regulatory pathways are integrated at the transcriptional regulation of FT and TSF.
Yamaguchi et al. (2005) Plant Cell Physiol. 46: 1175-1189
