Brisson L. F., Tenhaken R., Lamb C.
Plant Biology Laboratory, Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037.
Plant Cell. 1994 Dec;6(12):1703-1712. doi: 10.1105/tpc.6.12.1703.
Elicitation of soybean cells causes a rapid insolubilization of two cell wall structural proteins, p33 and p100. Likewise, a short elicitation of 30 min rendered cell walls more refractory to enzyme digestion as assayed by the yield of protoplasts released. This effect could be ascribed to protein cross-linking because of its insensitivity to inhibitors of transcription (actinomycin D) and translation (cycloheximide) and its induction by exogenous H2O2. Moreover, the induced loss of protoplasts could be prevented by preincubation with DTT, which also blocks peroxidase-mediated oxidative cross-linking. The operation of protein insolubilization in plant defense was also demonstrated by its occurrence in the incompatible interaction but not in the compatible interaction between soybean and Pseudomonas syringae pv glycinea. Likewise, protein insolubilization was observed in bean during non-host hypersensitive resistance to the tobacco pathogen P. s. pv tabaci mediated by the hypersensitive resistance and pathogenicity (Hrp) gene cluster. Our data strongly suggest that rapid protein insolubilization leads to a strengthened cell wall, and this mechanism functions as a rapid defense in the initial stages of the hypersensitive response prior to deployment of transcription-dependent defenses.
激发大豆细胞会导致两种细胞壁结构蛋白p33和p100迅速不溶。同样，30分钟的短暂激发使细胞壁对酶消化更具抗性，这通过释放原生质体的产量来测定。这种效应可归因于蛋白质交联，因为它对转录抑制剂（放线菌素D）和翻译抑制剂（环己酰亚胺）不敏感，并且可由外源H2O2诱导。此外，用二硫苏糖醇（DTT）预孵育可以防止诱导的原生质体损失，DTT也能阻断过氧化物酶介导的氧化交联。蛋白质不溶在植物防御中的作用也通过其在大豆与丁香假单胞菌大豆致病变种的不亲和相互作用中出现而在亲和相互作用中未出现得到证明。同样，在菜豆对烟草病原菌烟草致病变种的非寄主过敏反应中，由过敏反应和致病性（Hrp）基因簇介导，也观察到了蛋白质不溶现象。我们的数据强烈表明，快速的蛋白质不溶导致细胞壁强化，并且这种机制在转录依赖性防御展开之前的过敏反应初始阶段作为一种快速防御发挥作用。
