Anion channel sensitivity to cytosolic organic acids implicates a central role for oxaloacetate in integrating ion flux with metabolism in stomatal guard cells
| Autor: | Michael R. Blatt, Yizhou Wang |
|---|---|
| Přispěvatelé: | Laboratory of Plant Physiology and Biophysics, University of Glasgow |
| Jazyk: | angličtina |
| Rok vydání: | 2011 |
| Předmět: |
Oxaloacetic Acid
0106 biological sciences diurnal stomatal movement Malates Ac acetate ALMT12 aluminium-activated malate transporter 12 Mal malate Acetates Photosynthesis 01 natural sciences Biochemistry TEA-Cl tetraethylammonium chloride 03 medical and health sciences chemistry.chemical_compound Cytosol Guard cell Oxaloacetic acid cytosolic-free Ca2+ concentration Citrate synthase voltage clamp Molecular Biology 030304 developmental biology chemistry.chemical_classification 0303 health sciences biology Life Sciences Cell Biology Metabolism voltage-gated anion channel stomatal guard cell Vicia faba Electrophysiology organic acid metabolism [Ca2+]i cytosolic-free [Ca2+] chemistry Plant Stomata biology.protein OAA oxaloacetate Flux (metabolism) Research Article 010606 plant biology & botany Organic acid |
| Zdroj: | Biochemical Journal Biochemical Journal, Portland Press, 2011, 439 (1), pp.161-170. ⟨10.1042/BJ20110845⟩ |
| ISSN: | 0264-6021 1470-8728 |
| DOI: | 10.1042/BJ20110845⟩ |
| Popis: | Stomatal guard cells play a key role in gas exchange for photosynthesis and in minimizing transpirational water loss from plants by opening and closing the stomatal pore. The bulk of the osmotic content driving stomatal movements depends on ionic fluxes across both the plasma membrane and tonoplast, the metabolism of organic acids, primarily Mal (malate), and its accumulation and loss. Anion channels at the plasma membrane are thought to comprise a major pathway for Mal efflux during stomatal closure, implicating their key role in linking solute flux with metabolism. Nonetheless, little is known of the regulation of anion channel current (ICl) by cytosolic Mal or its immediate metabolite OAA (oxaloacetate). In the present study, we have examined the impact of Mal, OAA and of the monocarboxylic acid anion acetate in guard cells of Vicia faba L. and report that all three organic acids affect ICl, but with markedly different characteristics and sidedness to their activities. Most prominent was a suppression of ICl by OAA within the physiological range of concentrations found in vivo. These findings indicate a capacity for OAA to co-ordinate organic acid metabolism with ICl through the direct effect of organic acid pool size. The findings of the present study also add perspective to in vivo recordings using acetate-based electrolytes. |
| Databáze: | OpenAIRE |
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