Release of extracellular purines from plant roots and effect on ion fluxes
Release of extracellular purines from plant roots and effect on ion fluxes
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DOI：
10.4161/psb.6.11.17014
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发表时间：
2011-01-01
影响因子：
2.9
通讯作者：
Davies, Julia M.
中科院分区：
文献类型：
--
作者：
Dark, Adeeba;Demidchik, Vadim;Davies, Julia M.
细胞外嘌呤核苷酸通过部分地作为质膜钙通道的激动剂来调节植物的发育、防御和胁迫反应。刺激ATP释放的因素包括创伤、渗透胁迫和激发子。在这里，我们表明，外源脱落酸和L-谷氨酸也可以引起ATP积累拟南芥根周围。根表皮ADP的释放会触发质膜上的离子型受体样活性，导致胞质游离钙的瞬时升高。根表皮原生质体（表达水母发光蛋白作为胞质游离钙报告）可以支持细胞外ADP诱导的胞质钙升高的存在下，细胞外还原剂。这证实了ADP可以引起与ATP不同的基于钙的反应，ATP先前已经显示涉及细胞外活性氧的产生。
Extracellular purine nucleotides appear capable of regulating plant development, defense and stress responses by acting in part as agonists of plasma membrane calcium channels. Factors stimulating ATP release include wounding, osmotic stress and elicitors. Here we show that exogenous abscisic acid and l-glutamate can also cause ATP accumulation around Arabidopsis thaliana roots. Release of ADP from root epidermis would trigger ionotropic receptor-like activity in the plasma membrane, resulting in transient elevation of cytosolic free calcium. Root epidermal protoplasts (expressing aequorin as a cytosolic free calcium reporter) can support an extracellular ADP-induced cytosolic calcium elevation in the presence of an extracellular reductant. This confirms that ADP could elicit calcium-based responses distinct to those of ATP, which have been shown previously to involve production of extracellular reactive oxygen species.