These authors contributed equally to this work.
Very rapid phosphorylation kinetics suggest a unique role for Lhcb2 during state transitions in Arabidopsis
Article first published online: 25 AUG 2013
© 2013 The Authors The Plant Journal © 2013 John Wiley & Sons Ltd
This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.
The Plant Journal
Volume 76, Issue 2, pages 236–246, October 2013
How to Cite
Leoni, C., Pietrzykowska, M., Kiss, A. Z., Suorsa, M., Ceci, L. R., Aro, E.-M. and Jansson, S. (2013), Very rapid phosphorylation kinetics suggest a unique role for Lhcb2 during state transitions in Arabidopsis. The Plant Journal, 76: 236–246. doi: 10.1111/tpj.12297
- Issue published online: 5 OCT 2013
- Article first published online: 25 AUG 2013
- Accepted manuscript online: 25 JUL 2013 11:04AM EST
- Manuscript Accepted: 9 JUL 2013
- Manuscript Revised: 28 JUN 2013
- Manuscript Received: 31 OCT 2012
- European Union project FP7-PEOPLE-ITN-2008
- ‘HARVEST: Control of Light Use Efficiency in Plants and Algae From Light to Harvest’
- Swedish Research Council (VR)
- Swedish Research Council for Environment
- Agricultural Sciences and Spatial Planning (Formas)
- Academy of Finland (project Nos 118637 and 138703)
- 1-year fellowship from the University of Bari (Rectoral Decree No. 1598)
- state transitions
Light-harvesting complex II (LHCII) contains three highly homologous chlorophyll-a/b-binding proteins (Lhcb1, Lhcb2 and Lhcb3), which can be assembled into both homo- and heterotrimers. Lhcb1 and Lhcb2 are reversibly phosphorylated by the action of STN7 kinase and PPH1/TAP38 phosphatase in the so-called state-transition process. We have developed antibodies that are specific for the phosphorylated forms of Lhcb1 and Lhcb2. We found that Lhcb2 is more rapidly phosphorylated than Lhcb1: 10 sec of ‘state 2 light’ results in Lhcb2 phosphorylation to 30% of the maximum level. Phosphorylated and non-phosphorylated forms of the proteins showed no difference in electrophoretic mobility and dephosphorylation kinetics did not differ between the two proteins. In state 2, most of the phosphorylated forms of Lhcb1 and Lhcb2 were present in super- and mega-complexes that comprised both photosystem (PS)I and PSII, and the state 2-specific PSI–LHCII complex was highly enriched in the phosphorylated forms of Lhcb2. Our results imply distinct and specific roles for Lhcb1 and Lhcb2 in the regulation of photosynthetic light harvesting.