Malerba M, Cerana R, Crosti P
Dipartimento di Biotecnologie e Bioscienze, Università degli Studi di Milano-Bicocca, Piazza della Scienza 2, Milan, IT.
Protoplasma. 2003;222(3-4):113-6. doi: 10.1007/s00709-003-0023-5. Epub 2003 Dec 19.
Programmed cell death plays a pivotal role in several developmental processes of plants and it is involved in the response to environmental stresses and in the defense mechanisms against pathogen attack. It has not yet been defined which part of the death signalling mechanism and which molecules involved in programmed cell death are common to animals and plants. In this paper we show that fusicoccin, a well-known phytotoxin, induces a strong acceleration in the appearance of Evans Blue-stainable (dead) cells in sycamore (Acer pseudoplatanus L.) cultures. This fusicoccin-induced cell death shows aspects common to the form of animal programmed cell death termed apoptosis: i.e., cell shrinkage, changes in nucleus morphology, increase in DNA fragmentation detectable by a specific immunological reaction, and presence of oligonucleosomal-size fragments (laddering) in DNA gel electrophoresis. Since fusicoccin has a well-identified molecular target, the plasma membrane H(+)-ATPase, and thoroughly investigated physiological effects, this toxin appears to be a useful tool to study the transduction of death signals leading to programmed cell death in plants.
程序性细胞死亡在植物的多个发育过程中起着关键作用，并且参与植物对环境胁迫的响应以及对病原体攻击的防御机制。目前尚未明确动物和植物在死亡信号传导机制的哪一部分以及参与程序性细胞死亡的哪些分子是共同的。在本文中，我们表明，一种著名的植物毒素——壳梭孢菌素，可使悬铃木（Acer pseudoplatanus L.）培养物中伊文思蓝可染（死亡）细胞的出现强烈加速。这种壳梭孢菌素诱导的细胞死亡表现出与动物程序性细胞死亡形式（即凋亡）共有的特征：即细胞收缩、细胞核形态变化、通过特定免疫反应可检测到的DNA片段化增加，以及DNA凝胶电泳中存在寡核小体大小的片段（梯状条带）。由于壳梭孢菌素有一个明确的分子靶点——质膜H(+) -ATP酶，并且其生理效应已得到充分研究，这种毒素似乎是研究导致植物程序性细胞死亡的死亡信号转导的有用工具。
