NMT歷*的今天丨胞外ATP通過異源G蛋白和ROS促進氣孔開放
NMT是基因功能的活體檢測技術(shù),已被103位諾貝爾獎得主所在單位,及北大、清華、中科院使用。
NMT歷*的今天
2011年12月02日,河北師范大學(xué)尚忠林、郝立華、王偉霞、陳忱利用NMT在Molecular Plant 上發(fā)表了標(biāo)題為Extracellular ATP promotes stomatal opening of Arabidopsis thaliana through heterotrimeric G protein a subunit and reactive oxygen species的研究成果。
期刊:Molecular Plant
主題:胞外ATP通過異源G蛋白和ROS促進氣孔開放
標(biāo)題:Extracellular ATP promotes stomatal opening of Arabidopsis thaliana through heterotrimeric G protein a subunit and reactive oxygen species
影響因子:4.296
檢測指標(biāo):Ca2+、H+流速
作者:河北師范大學(xué)尚忠林、郝立華、王偉霞、陳忱
英文摘要
In recent years, adenosine tri-phosphate (ATP) has been reported to exist in apoplasts of plant cells as a signal molecule. Extracellular ATP (eATP) plays important roles in plant growth, development, and stress tolerance.
Here, extracellular ATP was found to promote stomatal opening of Arabidopsis thaliana in light and darkness. ADP, GTP, and weakly hydrolyzable ATP analogs (ATPγS, Bz-ATP, and 2meATP) showed similar effects, whereas AMP and adenosine did not affect stomatal movement. Apyrase inhibited stomatal opening. ATP-promoted stomatal opening was blocked by an NADPH oxidase inhibitor (diphenylene iodonium) or deoxidizer (dithiothreitol), and was impaired in null mutant of NADPH oxidase (atrbohD/F).
Added ATP triggered ROS generation in guard cells via NADPH oxidase. ATP also induced Ca2+ influx and H+ efflux in guard cells. In atrbohD/F, ATP-induced ion flux was strongly suppressed. In null mutants of the heterotrimeric G protein α subunit, ATP-promoted stomatal opening, cytoplasmic ROS generation, Ca2+ influx, and H+ efflux were all suppressed.
These results indicated that eATP-promoted stomatal opening possibly involves the heterotrimeric G protein, ROS, cytosolic Ca2+, and plasma membrane H+-ATPase.
中文摘要(谷歌機翻)
近年來,已經(jīng)報道三磷酸腺苷(ATP)作為信號分子存在于植物細(xì)胞的質(zhì)外體中。細(xì)胞外ATP(eATP)在植物生長,發(fā)育和脅迫耐受性中起重要作用。
在這里,發(fā)現(xiàn)細(xì)胞外ATP在光與暗中促進擬南芥氣孔的開放。ADP,GTP和弱水解性ATP類似物(ATPγS,Bz-ATP和2meATP)顯示出相似的作用,而AMP和腺苷并不影響氣孔運動。磷酸酶抑制氣孔開放。ATP促進的氣孔開放被NADPH氧化酶抑制劑(二亞苯基碘鎓)或脫氧劑(二硫蘇糖醇)阻止,并且在NADPH氧化酶的無效突變體(atrbohD / F)中受損。
添加的ATP通過NADPH氧化酶觸發(fā)了保衛(wèi)細(xì)胞中ROS的生成。ATP還誘導(dǎo)了保衛(wèi)細(xì)胞中Ca2 +的流入和H +的流出。在atrbohD / F中,ATP誘導(dǎo)的離子通量被強烈抑制。在異源三聚體G蛋白α亞基的無效突變體中,ATP促進的氣孔開放,細(xì)胞質(zhì)ROS生成,Ca2 +涌入和H +外排均被抑制。
這些結(jié)果表明,eATP促進的氣孔開放可能涉及異三聚體G蛋白,ROS,胞質(zhì)Ca2 +和質(zhì)膜H + -ATPase。
Figure 6ATP Stimulates Ca2+ Influx and H+Efflux in Guard Cells of Arabidopsis thaliana (Ecotype col-0).
(A) Gadolinium chloride (50 μM) blocked ATP-promoted stomatal opening.
(B) and (C) show time course of Ca2+ flux in MES buffer without (B) or with (C) epidermis before and after 0.6 mM ATP treatment, respectively. The arrow marks time points of ATP treatment.
(D) The dose-dependence of ATP-promoted Ca2+ influx; data are the means ± SE (n = 30) of the peak Ca2+ influx value after ATP stimulation. The positive and negative values of ion flux represent ion influx and efflux, respectively.
(E) Sodium vanadate (100 μM) blocked ATP-promoted stomatal opening.
(F) and (G) show time courses of H+ flux in MES buffer without (F) or with (G) epidermis before and after 0.6 mM ATP treatment, respectively.
The arrow marks time points of ATP treatment. In (A) and (E), data are means ± SE (n = 6) for stomatal aperture. In all figures, ‘control’ means treatment with MES buffer only. (H) The dose-dependence of ATP-promoted H+ influx; data are the means ± SE (n = 30) of the peak H+ efflux value after ATP stimulation.