A plastid protein crucial for Ca2+-regulated stomatal responses
Article first published online: 27 MAY 2008
© The Authors (2008). Journal compilation © New Phytologist (2008)
Volume 179, Issue 3, pages 675–686, August 2008
How to Cite
Weinl, S., Held, K., Schlücking, K., Steinhorst, L., Kuhlgert, S., Hippler, M. and Kudla, J. (2008), A plastid protein crucial for Ca2+-regulated stomatal responses. New Phytologist, 179: 675–686. doi: 10.1111/j.1469-8137.2008.02492.x
- Issue published online: 15 JUL 2008
- Article first published online: 27 MAY 2008
- Received: 4 March 2008Accepted: 10 April 2008
- Ca2+-sensing receptor (CAS);
- guard cells;
- signal transduction;
- stomatal movement.
- • Guard cell movements are regulated by environmental cues including, for example, elevations in extracellular Ca2+ concentration. Here, the subcellular localization and physiological function of the Ca2+-sensing receptor (CAS) protein was investigated.
- • CAS protein localization was ascertained by microscopic analyses of green fluorescent protein (GFP) fusion proteins and biochemical fractionation assays. Comparative guard cell movement investigations were performed in wild-type and cas loss-of-function mutant lines of Arabidopsis thaliana. Cytoplasmic Ca2+ dynamics were addressed in plants expressing the yellow cameleon reporter protein YC3.6.
- • This study identified CAS as a chloroplast-localized protein that is crucial for proper stomatal regulation in response to elevations of external Ca2+. CAS fulfils this role through modulation of the cytoplasmic Ca2+ concentration.
- • This work reveals a novel role of the chloroplast in cellular Ca2+ signal transduction.