Molecular Physiology of Signal Transduction in Guard Cells

保卫细胞信号转导的分子生理学

基本信息

批准号：
06044174
负责人：
SHIMAZAKI Ken-ichiro
金额：
$ 3.78万
依托单位：
KYUSHU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for international Scientific Research
财政年份：
1994
资助国家：
日本
起止时间：
1994 至 1995
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-06044174/
关键词：
Stomata Guard Cell Calcium Micrinjection Blue Lihgt Response Light signaling Pathway proton Pump Confocal Microscopy

项目摘要

Purity of the isolated plasma membrane from oat roots was examined by the sensitivity of ATP hydrolytic activity to vanadate. Vanadate strongly inhibited the ATP hydrolysis, but NO_3^-, oligomycin and ammonium molybdate had no significant inhibition of the hydrolysis, suggesting that isolated plasma membrane from oat had a high purity. Proton pumping activity measured by quinacrine quenching was inhibited strongly by Ca^<2+> at 1 muM.Similarly, proton pumping activity was inhibited by Ca^<2+> at 1 muM in isolated plasma membrane from spinach leaves. These results suggest that the proton pumping activity across the plasma memranes was inhibited by Ca^<2+> at physiological concentrations in both leaf an root tissue.We measured the cytosolic Ca^<2+> concentrations in guard cells of Commelina communis using confocal laser scanning microscope. In this experiments, we confirmed that the Ca^<2+> indicator of calcium orange and rhod 2 were both useful to measure Ca^<2+> in the guard cell cytosol. When EGTA was added to epidermal layrs, cytosolic Ca^<2+> concentration was declined and the removal of EGTA from the incubation media restored the Ca^<2+> concentration. The results suggest that the possible regulation for the plasma membrane proton pump activity by external application of EGTA.When the guard cell was illuminated with red light, we could not find any change in cytosolic Ca^<2+> concentration in guard cells.In isolated vacuole from guard cells, ABA had no effect on the vacuolar volume.

通过ATP水解活性对钒酸盐的敏感性，检查了燕麦根中分离的质膜的纯度。杂质强烈抑制ATP水解，但NO_3^ - ，寡霉素和钼酸铵对水解没有显着抑制，这表明从燕麦中分离出的质膜具有很高的纯度。在1摄氏度下，Ca^<2+>强烈抑制了通过喹诺氏猝灭测得的质子泵浦活性。相似地，在菠菜叶中分离的质膜中，在1 MMUM处的Ca^<2+>在1 MUM处抑制了质子泵送活性。这些结果表明，在两种叶子组织中，Ca^<2+>>在生理浓度下抑制了质子膜的质子泵浦活性。在此实验中，我们证实了橙色和Rhod 2钙的Ca^<2+>指标都可以在防护细胞胞质中测量Ca^<2+>有用。当将EGTA添加到表皮外行中时，胞质Ca^<2+>浓度下降，从孵育培养基中去除EGTA会恢复Ca^<2+>浓度。结果表明，通过外部应用EGTA对质膜质子泵活性的可能调节。当护罩细胞被红光照亮时，我们找不到在护罩细胞中的胞质Ca^<2+>浓度的任何变化。从护罩细胞中分离出的真空吸尘器，ABA对液泡量没有影响。