Regulation of flowering time in Arabidopsis



FIBR homepage


Flowering pathway

Gibberellin pathway



The Gibberellin transduction pathway


interaction between AtMYB33 and LFY


AtMYB33 may be a transcriptional activator of LFY:

The LFY promoter contains a GARE motif (GA-Responsive Element), a very conserved sequence that is a putative binding site for MYB transcription factors (Gubler et al., 1999). The GARE motif is necessary for GA induction of LFY (Blazquez and Weigel, 2000; Gocal et al., 2001). The suppression of this motif makes LFY insensitive to GAs, and also reduces LFY activity, particularly in short days (Blazquez and Weigel, 2000).

Gocal and colleagues (2001) observed that, in E. coli, the AtMYB33 transcription factor is able to bind to the GARE motif on the LFY promoter. However, this has not been observed in planta.

The profile of MYB33 transcript accumulation is correlated with LFY activity, which is consistent with the hypothesis that MYB33 is a transcriptional activator of LFY (Achard et al., 2004).