The Histidine Kinase AHK5 Integrates Endogenous and Environmental Signals in Arabidopsis Guard Cells

Warning

This publication doesn't include Faculty of Economics and Administration. It includes Faculty of Science. Official publication website can be found on muni.cz.

Authors	DESIKAN Radhika HORÁK Jakub CHABAN Christina MIRA-RODADO Virtudes WITTHÖFT Janika ELGASS Kirstin GREFEN Christopher CHEUNG Man-Kim MEIXNER Alfred J HOOLEY Richard NEILL Steven John HANCOCK John Travers HARTER Klaus
Year of publication	2008
Type	Article in Periodical
Magazine / Source	PloS ONE
MU Faculty or unit	Faculty of Science
Citation
Web	http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0002491
Field	Genetics and molecular biology
Keywords	two-component system; AHK; signal transduction; hydrogene peroxide; stomata; Arabidopsis
Description	Stomatal guard cells monitor and respond to environmental and endogenous signals such that the stomatal aperture is continually optimised for water use efficiency. A key signalling molecule produced is hydrogen peroxide (H2O2). Here, we identify a pathway by which H2O2 is sensed and transduced to effect stomatal closure. Histidine kinases (HK) are part of two-component signal transduction systems that act to integrate environmental stimuli into a cellular response via a phosphotransfer relay mechanism. Here we report that in addition to the predicted cytoplasmic localisation of this protein, AHK5 also appears to co-localise to the plasma membrane. Although AHK5 is expressed at low levels in guard cells, we identify a unique role for AHK5 in stomatal signalling. Our findings identify an integral signalling function for AHK5 that acts to integrate multiple signals via H2O2 homeostasis and is independent of ABA signalling in guard cells.
Related projects:	Molecular basis of cell and tissue regulations