PKS1 and PKS2 affect the phyA state in etiolated Arabidopsis seedlings.
Details
Serval ID
serval:BIB_FCF2721FC572
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
PKS1 and PKS2 affect the phyA state in etiolated Arabidopsis seedlings.
Journal
Photochemical and Photobiological Sciences
ISSN
1474-905X (Print)
ISSN-L
1474-905X
Publication state
Published
Issued date
2004
Peer-reviewed
Oui
Volume
3
Number
6
Pages
608-611
Language
english
Notes
Publication types: Journal Article ; Research Support, Non-U.S. Gov't
Publication Status: ppublish
Publication Status: ppublish
Abstract
Autophosphorylation of phytochrome A (phyA) and transphosphorylation of its reaction partners, phytochrome kinase substrate 1 (PKS1) in particular, might play important functions in signal transduction from phyA. It was shown that PKS1 and PKS2 physically interact with phyA and phyB in vitro, and that overexpression of PKS1 interferes with phytochrome signaling in vivo. Moreover, both pks1 and pks2 loss of function mutants are specifically defective for one branch of phyA signaling. We therefore used in vivo fluorescence spectroscopy to test whether mutations in pks1 and pks2 or overexpression of PKS1 (PKS1OX) have an effect on phyA and its subpopulations, phyA' and phyA''. It was found that the emission spectra of phyA in all the Arabidopsis lines are similar. The phyA content in the single mutants pks1 and pks2, and also in PKS1OX, was 1.2-1.5 times higher than in the wild type, whereas the phyA'/phyA'' ratio remained practically unchanged (approx. 1.0). However, in the double mutant pks1pks2, the picture is reversed--the phyA concentration remained unchanged, while the phyA'/phyA'' ratio shifted dramatically towards phyA''(0.3). This suggests that (i) the changes in PKS1 or PKS2 content may affect the total phyA concentration, (ii) PKS1, together with PKS2, could be critical for the formation of phyA', thus shifting the equilibrium towards phyA'' in the double mutant and (iii) these variations in the phyA' and phyA'' content may contribute to the mutant phenotype of pks1, pks2 and PKS1OX. The fact that in the single mutants there are only small changes in the phyA'/phyA'' ratio, while in the double mutant the ratio is considerably affected, indicates that PKS1 or PKS2 act redundantly with each other in this regard.
Keywords
Arabidopsis/genetics, Arabidopsis/growth & development, Arabidopsis Proteins/genetics, Arabidopsis Proteins/metabolism, Cotyledon/physiology, Darkness, Intracellular Signaling Peptides and Proteins/genetics, Intracellular Signaling Peptides and Proteins/metabolism, Mutation, Phosphoproteins/genetics, Phosphoproteins/metabolism, Seedling/growth & development, Spectrometry, Fluorescence, Temperature
Pubmed
Web of science
Create date
24/01/2008 16:29
Last modification date
20/08/2019 17:27