An evolutionary view on thylakoid protein phosphorylation uncovers novel phosphorylation hotspots with potential functional implications.
The regulation of photosynthetic light reactions by reversible protein phosphorylation is well established today, but functional studies have so far mostly been restricted to processes affecting light-harvesting complex II and the core proteins of photosystem II. Virtually no functional data are available on regulatory effects at the other photosynthetic complexes despite the identification of multiple phosphorylation sites. Therefore we summarize the available data from 50 published phospho-proteomics studies covering the main complexes involved in photosynthetic light reactions in the 'green lineage' (i.e. green algae and land plants) as well as its cyanobacterial counterparts. In addition, we performed an extensive orthologue search for the major photosynthetic thylakoid proteins in 41 sequenced genomes and generated sequence alignments to survey the phylogenetic distribution of phosphorylation sites and their evolutionary conservation from green algae to higher plants. We observed a number of uncharacterized phosphorylation hotspots at photosystem I and the ATP synthase with potential functional relevance as well as an unexpected divergence of phosphosites. Although technical limitations might account for a number of those differences, we think that many of these phosphosites have important functions. This is particularly important for mono- and dicot plants, where these sites might be involved in regulatory processes such as stress acclimation.
Department of Ecogenomics and Systems Biology, University of Vienna, Althanstr. 14, A-1090 Vienna, Austria.
Michele
M
Grieco
Department for Applied Bioinformatics, Institute for Cell Biology and Neuroscience, Goethe University, Max-von-Laue Str. 13, D-60438 Frankfurt, Germany.
Arpit
A
Jain
Department for Applied Bioinformatics, Institute for Cell Biology and Neuroscience, Goethe University, Max-von-Laue Str. 13, D-60438 Frankfurt, Germany Senckenberg Biodiversity and Climate Research Centre (BiK-F), Senckenberg Anlage 25, D-60325 Frankfurt, Germany.
Ingo
I
Ebersberger
Department of Ecogenomics and Systems Biology, University of Vienna, Althanstr. 14, A-1090 Vienna, Austria markus.teige@univie.ac.at.
Markus
0000-0001-7204-1379
M
Teige
D000458:Cyanobacteria / Q000378:metabolism*; D019143:Evolution, Molecular; D010766:Phosphorylation; D010940:Plant Proteins / Q000378:metabolism*; D010944:Plants / Q000378:metabolism*; D060431:Thylakoid Membrane Proteins / Q000378:metabolism*; D020524:Thylakoids / Q000378:metabolism*
D010940:Plant Proteins; D060431:Thylakoid Membrane Proteins
Acclimation to stress; calcium signal; chloroplast; evolution; light-harvesting; photosynthesis; protein phosphorylation; signalling.