The timing with which plants switch from producing only vegetative tissue to producing flowers as well is regulated by a complex interplay of time, day length, and light. Kardailsky et al. and Kobayashi et al. have characterized the Arabidopsis gene FT (FLOWERING LOCUS T) and show that, seemingly in parallel with LFY (LEAFY), it regulates floral transition. Although FT is similar in sequence to the TFL (TERMINAL FLOWER) gene, their functions are divergent. Thus, the complex genetic network that regulates the onset of flowering is brought into view.
Kobayashi, Y., Kaya, H., Goto, K., Iwabuchi, M., and Araki, T. (1999) A pair of related genes with antagonistic roles in mediating flowering signals. Science 286: 1960-1962. [Abstract] [Full Text]
Kardailsky, I., Shukla, V.K., Ahn, J.H., Dagenais, N., Christensen, S.K., Nguyen, J.T., Chory, J., Harrison, M.J., and Weigel, D. (1999) Activation tagging of the floral inducer FT. Science 286: 1962-1965. [Abstract] [Full Text]