Ca2+ signalling in stomatal guard cells. (August 2000)

• Record Type: Journal Article
• Authors: McAinsh, M. R.; Gray, J. E.; Hetherington, A. M.; Leckie, C. P.; Ng, C.
• Is Part Of: Biochemical Society transactions. Volume 28:Number 4(2000)
• Page Start: 476
• Page End: 481
• Publication Date: 2000-08
• Subjects: calcium signalling -- stomata -- specificity; ABA, abscisic acid -- [Ca2+]cyt, cytosolic free Ca2+ concentration -- [Ca2+]ext, external Ca2+ concentration -- DAG, diacylglygerol -- Ins(1, 4, 5)P3R, Ins(1, 4, 5)P3 receptor -- Kin, plasma membrane inward-rectifying K+ channel -- PLC, phospholipase C -- RyR, ryanodine receptor -- U-73122, 1-(6-{[17β-3-methoxyestra-1, 3, 5(10)-trien-17-yl]amino}hexyl)-1H-pyrrole-2, 5-dione; Biochemistry -- Congresses; 572
• DOI: 10.1042/bst0280476
• Languages: English
• ISSNs: 0300-5127

Abstract

Abstract : Ca 2+ is a ubiquitous second messenger in the signal transduction pathway(s) by which stomatal guard cells respond to external stimuli. Increases in guard-cell cytosolic free Ca 2+ concentration ([Ca 2+ ]cyt ) have been observed in response to stimuli that cause both stomatal opening and closure. In addition, several important components of Ca 2+ -based signalling pathways have been identified in guard cells, including the cADP-ribose and phospholipase C/Ins(1, 4, 5) P 3 -mediated Ca 2+ -mobilizing pathways. The central role of stimulus-induced increases in [Ca 2+ ]cyt in guard-cell signal transduction has been clearly demonstrated in experiments examining the effects of modulating increases in [Ca 2+ ]cyt on alterations in guard-cell turgor or the activity of ion channels that act as effectors in the guard-cell turgor response. In addition, the paradox that Ca 2+ is involved in the transduction of signals that result in opposite end responses (stomatal opening and closure) might be accounted for by the generation of stimulus-specific Ca 2+ signatures, such that increases in [Ca 2+ ]cyt exhibit unique spatial and temporal characteristics.