First published online July 10, 2007
Development 134, 1504e (2007)
© The Company of Biologists Limited
Burst into bloom with brassinosteroids
For plants, accurate timing of the transition from vegetative to
reproductive growth maximizes reproductive success. The transition is known to
be controlled by numerous interacting endogenous and environmental factors,
but more, it seems, remain to be discovered. On
p. 2841, Domagalska
and colleagues describe an unexpected role for brassinosteroid signalling -
namely, the regulation of expression of FLOWERING LOCUS C
(FLC), a potent floral repressor - in the control of flowering time
in Arabidopsis thaliana. Brassinosteroids are plant steroid hormones
that signal through a receptor-like kinase called BRASSINOSTEROID INSENSITIVE
1 (BRI1). The researchers identify two alleles of bri1 that are
strong enhancers of several flowering-time mutants. Double mutants that
combine bri1 (or cpd, a brassinosteroid-deficient mutant)
with known flowering-time mutants (for example, luminidependens)
express raised levels of FLC transcripts, they report, which leads to
extremely late flowering. RNAi directed against the FLC transcript
reverses this phenotype. The researchers propose, therefore, that
brassinosteroid signalling regulates FLC expression and thus helps to
control flowering time.
Related articles in Development:
- Attenuation of brassinosteroid signaling enhances FLC expression and delays flowering
- Malgorzata A. Domagalska, Fritz M. Schomburg, Richard M. Amasino, Richard D. Vierstra, Ferenc Nagy, and Seth J. Davis
Development 2007 134: 2841-2850.
[Abstract]
[Full Text]
