| Title: | Plant volatiles regulate the activities of Ca2+ -permeable channels and promote cytoplasmic calcium transients in Arabidopsis leaf cells |
| Author(s): | Asai N; Nishioka T; Takabayashi J; Furuichi T; |
| Address: | "Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Corporation, Kawaguchi, Saitama, Japan" |
| ISSN/ISBN: | 1559-2324 (Electronic) 1559-2316 (Print) 1559-2316 (Linking) |
| Abstract: | "A variety of plant species emit volatile compounds in response to mechanical stresses such as herbivore attack. Although these volatile compounds promote gene expression leading to anti-herbivore responses, the underlying transduction mechanisms are largely unknown. While indirect evidence suggests that the cytoplasmic free Ca(2+) concentration ([Ca(2+)](c)) plays a crucial role in the volatile-sensing mechanisms in plants, these roles have not been directly demonstrated. In the present study, we used Arabidopsis leaves expressing apoaequorin, a Ca(2+)-sensitive luminescent protein, in combination with a luminometer, to monitor [Ca(2+)](c) transients that occur in response to a variety of volatile compounds and to characterized the pharmacological properties of the increase in [Ca(2+)](c). When leaves were exposed to volatiles, [Ca(2+)](c) was transiently raised. The [Ca(2+)](c) increases induced by acyclic compounds were disrupted by Ruthenium Red, a potential plasma-membrane and endo-membrane Ca(2+)-permeable channel inhibitor, but not by 1,2-bis(2-aminophenoxy) ethane-N,N,N',N'-tetraacetic acid (BAPTA), an extracellular Ca(2+)-chelator, suggesting that acyclic compounds promote Ca(2+)-release from intracellular stores. On the other hand, the electrophilic compound (E)-2-hexenal promoted Ca(2+)-influx via ROS production by natural oxidation at the aquarius phase. In a gpa1-2 mutant lacking a canonical Galpha subunit, the [Ca(2+)](c) transients induced by all tested volatiles were not attenuated, suggesting that G-protein coupled receptors are not involved in the volatile-induced [Ca(2+)](c) transients in Arabidopsis leaves" |
| Keywords: | "Aequorin/metabolism Apoproteins/metabolism Arabidopsis/cytology/*metabolism Arabidopsis Proteins/metabolism Calcium/*metabolism Calcium Channel Blockers/pharmacology Calcium Channels/*metabolism Cytoplasm/metabolism Gene Expression Regulation, Plant Plant;" |
| Notes: | "MedlineAsai, Naoko Nishioka, Takaaki Takabayashi, Junji Furuichi, Takuya eng Research Support, Non-U.S. Gov't 2009/10/02 Plant Signal Behav. 2009 Apr; 4(4):294-300. doi: 10.4161/psb.4.4.8275" |
