Zentrum für Biochemie und Molekularbiologie, Universität Kiel, Kiel, Germany.
Plant Signal Behav. 2010 Apr;5(4):379-85. doi: 10.4161/psb.5.4.10717. Epub 2010 Apr 20.
Plants respond to almost any kind of external stimulus with transients in their cytoplasmic free calcium concentration (Ca(2+)). A huge variety of kinetics recorded by optical techniques has been reported in the past. This variety has been credited the specificity needed to explain how information about incoming stimuli is evaluated by the organism and turned into the right physiological responses which provide advantages for survival and reproduction. A physiological response often takes place away from the site of stimulation. This requires cell-to-cell communication. Hence, responding cells are not necessarily directly stimulated but rather receive an indirect stimulus via cell-to-cell communication. It appears unlikely that the 'Ca(2+) signature' in the primarily stimulated cell is conveyed over long distances via cell-to-cell communication from the 'receptor cells' to the 'effector cells'. Here, a novel aspect is highlighted to explain the variety of [Ca(2+)] kinetics seen by integrating methods of Ca(2+) recording. Plants can generally be seen as cellular automata with specific morphology and capable for cell-to-cell communication. Just a few rules are needed to demonstrate how waves of Ca(2+)-increases percolate through the organism and thereby deliver a broad variety of 'signatures'. Modelling intercellular signalling may be a possible way to find explanations for different kinds of signal transmission, signal amplification, wave formation, oscillations and stimulus-response coupling. The basic examples presented here show that care has to be taken when interpreting cellular 'Ca(2+) signatures' recorded by optical techniques which integrate over a big number of cells or even whole plants.
植物会对几乎任何类型的外部刺激做出细胞质游离钙浓度 (Ca(2+)) 的瞬时变化反应。过去已经报道了通过光学技术记录的大量动力学变化。这种多样性被认为是解释生物体如何评估传入刺激信息并将其转化为正确的生理反应所必需的特异性，这些反应为生存和繁殖提供了优势。生理反应通常发生在刺激部位之外。这需要细胞间的通讯。因此，反应细胞不一定直接受到刺激，而是通过细胞间通讯接收间接刺激。似乎不太可能的是，在主要受刺激的细胞中，“Ca(2+) 特征”通过细胞间通讯从“受体细胞”传递到“效应细胞”，从而在长距离上传导。在这里，强调了一个新的方面来解释通过整合 Ca(2+) 记录方法来观察到的各种 [Ca(2+)]动力学。植物通常可以被视为具有特定形态和细胞间通讯能力的细胞自动机。只需要很少的规则就可以演示如何通过增加 Ca(2+) 波在整个生物体中传播，从而提供广泛的“特征”。细胞间信号转导的建模可能是寻找不同类型信号传输、信号放大、波形成、振荡和刺激-反应耦合的解释的一种可能方法。这里提出的基本示例表明，在解释通过光学技术记录的细胞“Ca(2+) 特征”时，需要小心谨慎，因为这些特征是通过对大量细胞甚至整个植物进行积分得到的。
