Skalamera D, Heath M C
Department of Botany, University of Toronto, 25 Willcocks St, Toronto, Ontario M5S 3B2, Canada.
Plant J. 1998 Oct;16(2):191-200. doi: 10.1046/j.1365-313x.1998.00285.x.
During the infection of cowpea (Vigna unguiculata) by the cowpea rust fungus (Uromyces vignae, race 1 ) the plant nucleus moves towards and away from the invading hypha and eventually moves close to the fungus in the susceptible cultivar while it remains away in two cultivars which subsequently respond by resistance gene-dependent plant cell death (the hypersensitive response, HR). The role of plant cytoskeleton in these responses was investigated by fluorescent microscopy and treatments with anticytoskeletal drugs. Observations of microtubule organization prior to cell death revealed that the sequence of events leading to protoplast collapse differed between the two resistant cultivars, suggesting a possibility of multiple pathways for cellular degradation during the HR. Different fixations produced two different microfilament patterns: a filament network and cables. Microfilament network remained visible even at later stages of cell death. Oryzalin and taxol reduced the incidence of autofluorescence that develops late in the death process, indicating a role of microtubules in the deposition of phenolics by adjacent living cells. Cell death and nuclear movements were not affected by oryzalin and taxol but were inhibited by cytochalasin E, suggesting that the microfilaments are required for the HR.
在豇豆锈病菌（豇豆单胞锈菌，1号小种）侵染豇豆（Vigna unguiculata）的过程中，在感病品种中，植物细胞核会朝着入侵菌丝移动然后又远离，最终靠近真菌；而在另外两个品种中，细胞核则一直保持远离状态，随后这两个品种会通过依赖抗性基因的植物细胞死亡（过敏反应，HR）做出反应。通过荧光显微镜观察以及使用抗细胞骨架药物进行处理，研究了植物细胞骨架在这些反应中的作用。对细胞死亡前微管组织的观察表明，导致两个抗性品种原生质体崩溃的事件顺序不同，这表明在过敏反应期间细胞降解可能存在多种途径。不同的固定方法产生了两种不同的微丝模式：丝状网络和索状结构。即使在细胞死亡后期，微丝网络仍然可见。oryzalin（一种除草剂）和紫杉醇降低了在死亡过程后期出现的自发荧光的发生率，表明微管在相邻活细胞酚类物质沉积中发挥作用。细胞死亡和细胞核移动不受oryzalin和紫杉醇的影响，但被细胞松弛素E抑制，这表明微丝是过敏反应所必需的。
