The stomatal apparatus consists of a pair of guard cells and regulates gas exchange between the leaf and atmosphere. In guard cells, blue light (BL) activates H(+)-ATPase in the plasma membrane through the phosphorylation of its penultimate threonine, mediating stomatal opening. Although this regulation is thought to be widely adopted among kidney-shaped guard cells in dicots, the molecular bas...

Drought induces stomatal closure, a response that is associated with the activation of plasma membrane anion channels in guard cells, by the phytohormone abscisic acid (ABA). In several species, this response is associated with changes in the cytoplasmic free Ca concentration. In Vicia faba, however, guard cell anion channels activate in a Ca-independent manner. Because of potential differences...

Drought induces stomatal closure, a response that is associated with the activation of plasma membrane anion channels in guard cells, by the phytohormone abscisic acid (ABA). In several species, this response is associated with changes in the cytoplasmic free Ca(2+) concentration. In Vicia faba, however, guard cell anion channels activate in a Ca(2+)-independent manner. Because of potential dif...

Oligomer-based DNA Affymetrix GeneChips representing about one-third of Arabidopsis (Arabidopsis thaliana) genes were used to profile global gene expression in a single cell type, guard cells, identifying 1309 guard cell–expressed genes. Highly pure preparations of guard cells and mesophyll cells were isolated in the presence of transcription inhibitors that prevented induction of stress-induci...

Oligomer-based DNA Affymetrix GeneChips representing about one-third of Arabidopsis (Arabidopsis thaliana) genes were used to profile global gene expression in a single cell type, guard cells, identifying 1309 guard cell-expressed genes. Highly pure preparations of guard cells and mesophyll cells were isolated in the presence of transcription inhibitors that prevented induction of stress-induci...

High resolution chlorophyll a fluorescence imaging was used to compare the photosynthetic efficiency of PSII electron transport (estimated by Fq'/Fm') in guard cell chloroplasts and the underlying mesophyll in intact leaves of six different species: Commelina communis, Vicia faba, Amaranthus caudatus, Polypodium vulgare, Nicotiana tabacum, and Tradescantia albifora. While photosynthetic efficie...

Water is the major factor limiting the growth and development of many land plants, and stomata, composed of two guard cells, are the chief gates controlling plants’ water loss. Many environmental and physiological stimuli control stomatal opening, but they all do so through the regulation of guard-cell osmolarity. Increased guard-cell osmolarity leads to the opening of the stomata and decreased...

5-aminolevulinic acid (ALA), a new plant growth regulator, can inhibit stomatal closure by reducing H2O2 accumulation in guard cells. Flavonols are a main kind of flavonoids and have been proposed as H2O2 scavengers in guard cells. 5-aminolevulinic acid can significantly improve flavonoids accumulation in plants. However, whether ALA increases flavonols content in guard cells and the role of fl...

Fructose 2,6-bisphosphate (Fru2,6P(2)) appears to function as a regulator metabolite in glycolysis and gluconeogenesis in animal tissues, yeast, and the photosynthetic cells of leaves. We have investigated the role of Fru2,6P(2) in guard-cell protoplasts from Vicia faba L. and Pisum sativum L. (Argenteum mutant), and in epidermal strips purified by sonication from all cells except for the guard...

We recently showed that treatment with actin antagonists perturbed stomatal behavior in Commelina communis L. leaf epidermis and therefore suggested that dynamic changes in actin are necessary for signal responses in guard cells (M. Kim, P.K. Hepler, S.O. Eun, K.-S. Ha, Y. Lee [1995] Plant Physiol 109: 1077-1084). Here we show that actin filaments of guard cells, visualized by immunofluorescenc...