Stomatal pores are formed by pairs of specialized epidermal guard cells and serve as major gateways for both CO2 influx into plants from the atmosphere and transpirational water loss of plants. Because they regulate stomatal pore apertures via integration of both endogenous hormonal stimuli and environmental signals, guard cells have been highly developed as a model system to dissect the dynamics and mechanisms of plant-cell signaling. The stress hormone ABA and elevated levels of CO2 activate complex signaling pathways in guard cells that are mediated by kinases/phosphatases, secondary messengers, and ion channel regulation. Recent research in guard cells has led to a new hypothesis for how plants achieve specificity in intracellular calcium signaling: CO2 and ABA enhance (prime) the calcium sensitivity of downstream calcium-signaling mechanisms. Recent progress in identification of early stomatal signaling components are reviewed here, including ABA receptors and CO2-binding response proteins, as well as systems approaches that advance our understanding of guard cell-signaling mechanisms.
|Original language||English (US)|
|Number of pages||31|
|Journal||Annual Review of Plant Biology|
|State||Published - May 4 2010|
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledged KAUST grant number(s): KUS-F1–021-31
Acknowledgements: We thank Drs. Jaakko Kangasjärvi (University of Helsinki) and Jeff Leung (CNRS Gif-sur-Yvette), and Cawas Engineer, Felix Hauser, and Katharine Hubbard in our laboratory (UCSD) for critical comments on manuscript versions and sections. Research in the Schroeder Lab is funded by grants from the National Science Foundation (MCB0417118), the National Institutes of Health (GM060396-ES010337), the Department of Energy (DE-FG02–03ER15449), and the Human Frontier Science Program. Maik Böhmer was supported by a research fellowship from the Deutsche Forschungsgemeinschaft, and Honghong Hu was supported by fellowship No. KUS-F1–021-31 from the King Abdullah University of Science and Technology (KAUST). We apologize to colleagues whose relevant work we were not able to cite and discuss because of space constraints.
This publication acknowledges KAUST support, but has no KAUST affiliated authors.