Stomatal spacing safeguards stomatal dynamics by facilitating guard cell ion transport independent of the epidermal solute reservoir

Maria Papanatsiou, Anna Amtmann, Michael R. Blatt*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

Abstract

Stomata enable gaseous exchange between the interior of the leaf and the atmosphere through the stomatal pore. Control of the pore aperture depends on osmotic solute accumulation by, and its loss from the guard cells surrounding the pore. Stomata in most plants are separated by at least one epidermal cell, and this spacing is thought to enhance stomatal function, although there are several genera that exhibit stomata in clusters. We made use of Arabidopsis (Arabidopsis thaliana) stomatal patterning mutants to explore the impact of clustering on guard cell dynamics, gas exchange, and ion transport of guard cells. These studies showed that stomatal clustering in the Arabidopsis too many mouths (tmm1) mutant suppressed stomatal movements and affected CO2 assimilation and transpiration differentially between dark and light conditions and were associated with alterations in K+ channel gating. These changes were consistent with the impaired dynamics of tmm1 stomata and were accompanied by a reduced accumulation of K+ ions in the guard cells. Our findings underline the significance of spacing for stomatal dynamics. While stomatal spacing may be important as a reservoir for K+ and other ions to facilitate stomatal movements, the effects on channel gating, and by inference on K+ accumulation, cannot be explained on the basis of a reduced number of epidermal cells facilitating ion supply to the guard cells.

Original languageEnglish
Pages (from-to)254-263
Number of pages10
JournalPlant physiology
Volume172
Issue number1
Early online date11 Jul 2016
DOIs
Publication statusPublished - 1 Sep 2016

Fingerprint

Dive into the research topics of 'Stomatal spacing safeguards stomatal dynamics by facilitating guard cell ion transport independent of the epidermal solute reservoir'. Together they form a unique fingerprint.

Cite this