An intermolecular disulfide-based light switch for chloroplast psbD gene expression in Chlamydomonas reinhardtii
Article first published online: 13 SEP 2012
© 2012 The Authors. The Plant Journal © 2012 Blackwell Publishing Ltd
The Plant Journal
Volume 72, Issue 3, pages 378–389, November 2012
How to Cite
Schwarz, C., Bohne, A.-V., Wang, F., Cejudo, F. J. and Nickelsen, J. (2012), An intermolecular disulfide-based light switch for chloroplast psbD gene expression in Chlamydomonas reinhardtii. The Plant Journal, 72: 378–389. doi: 10.1111/j.1365-313X.2012.05083.x
- Issue published online: 29 OCT 2012
- Article first published online: 13 SEP 2012
- Accepted manuscript online: 22 JUN 2012 01:27PM EST
- Received 12 September 2011; revised 30 May 2012; accepted 15 June 2012; published online 13 September 2012.
- Chlamydomonas ;
- chloroplast gene expression;
- redox control;
- ribonucleoprotein particle
Expression of the chloroplast psbD gene encoding the D2 protein of the photosystem II reaction center is regulated by light. In the green alga Chlamydomonas reinhardtii, D2 synthesis requires a high-molecular-weight complex containing the RNA stabilization factor Nac2 and the translational activator RBP40. Based on size exclusion chromatography analyses, we provide evidence that light control of D2 synthesis depends on dynamic formation of the Nac2/RBP40 complex. Furthermore, 2D redox SDS–PAGE assays suggest an intermolecular disulfide bridge between Nac2 and Cys11 of RBP40 as the putative molecular basis for attachment of RBP40 to the complex in light-grown cells. This covalent link is reduced in the dark, most likely via NADPH-dependent thioredoxin reductase C, supporting the idea of a direct relationship between chloroplast gene expression and chloroplast carbon metabolism during dark adaption of algal cells.