Plant and Cell Physiology Advance Access published online on November 6, 2008
Plant and Cell Physiology, doi:10.1093/pcp/pcn167
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Post-translational modifications of the endogenous and transgenic FLC protein in Arabidopsis thaliana
1CSIRO Plant Industry, GPO Box 1600, Canberra ACT 2601 Australia
Corresponding author: Dr. Masumi Robertson, CSIRO Plant Industry GPO Box 1600 Canberra ACT 2601 Australia, Ph: +61 2 6246-5030, Fax: +61 2 6246-5000, Masumi.robertson{at}csiro.au
| Abstract |
|---|
FLC is a MADS box transcription factor that acts as a dosage dependent repressor of flowering. We carried out a 2D gel analysis and showed that the majority of endogenous FLC and overexpressed FLC-FLAG proteins are post-translationally modified. The endogenous and transgenic proteins have different floral repressor activities; however they have similar, if not the same, profiles of post-translational modifications. The protein modification profile was also not changed by vernalisation treatment. The activities of other MADS box proteins have been shown to be affected by phosphorylation and we found that both the endogenous FLC and the transgenic FLC-FLAG protein are phosphorylated. When eight potential Ser kinase target sites in FLC were changed to mimic phosphorylated residues, expression of the mutant FLC-FLAG protein led to early flowering, suggesting that the repressive function was abolished. When the same eight Ser residues were changed to non-phosphorylatable residues, expression of the resulting protein gave the same weak flowering repression as over-expressed unmodified FLC-FLAG. The non-phosphorylatable variant of FLC-FLAG showed a similar spectrum of post-translational modifications as unmodified FLC-FLAG, indicating that modifications other than the predicted phosphorylations occur. Our data provide evidence for a post-translational regulation of FLC function.
Keywords: Arabidopsis - FLC - flowering time - phosphorylation - post-translational modification
(Received September 19, 2008; Accepted October 28, 2008)
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
M. Spensley, J.-Y. Kim, E. Picot, J. Reid, S. Ott, C. Helliwell, and I. A. Carre Evolutionarily Conserved Regulatory Motifs in the Promoter of the Arabidopsis Clock Gene LATE ELONGATED HYPOCOTYL PLANT CELL, September 1, 2009; 21(9): 2606 - 2623. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. Mitsuda and M. Ohme-Takagi Functional Analysis of Transcription Factors in Arabidopsis Plant Cell Physiol., July 1, 2009; 50(7): 1232 - 1248. [Abstract] [Full Text] [PDF] |
||||
![]() |
Compiled by, F. Tooke, T. Chiurugwi, and N. Battey Flowering Newsletter bibliography for 2008 J. Exp. Bot., June 23, 2009; (2009) erp154v1. [Full Text] [PDF] |
||||


