Krüger Julia, Thomas Colwyn M, Golstein Catherine, Dixon Mark S, Smoker Matthew, Tang Saijun, Mulder Lonneke, Jones Jonathan D G
The Sainsbury Laboratory, John Innes Centre, Norwich NR4 7UH, UK.
Science. 2002 Apr 26;296(5568):744-7. doi: 10.1126/science.1069288.
Little is known of how plant disease resistance (R) proteins recognize pathogens and activate plant defenses. Rcr3 is specifically required for the function of Cf-2, a Lycopersicon pimpinellifolium gene bred into cultivated tomato (Lycopersicon esculentum) for resistance to Cladosporium fulvum. Rcr3 encodes a secreted papain-like cysteine endoprotease. Genetic analysis shows Rcr3 is allelic to the L. pimpinellifolium Ne gene, which suppresses the Cf-2-dependent autonecrosis conditioned by its L. esculentum allele, ne (necrosis). Rcr3 alleles from these two species encode proteins that differ by only seven amino acids. Possible roles of Rcr3 in Cf-2-dependent defense and autonecrosis are discussed.
关于植物抗病（R）蛋白如何识别病原体并激活植物防御反应，我们所知甚少。Rcr3是Cf-2功能所特需的，Cf-2是野生醋栗番茄（Lycopersicon pimpinellifolium）中的一个基因，已被培育到栽培番茄（Lycopersicon esculentum）中，用于抵抗番茄叶霉病菌（Cladosporium fulvum）。Rcr3编码一种分泌型类木瓜蛋白酶半胱氨酸内切蛋白酶。遗传分析表明，Rcr3与野生醋栗番茄的Ne基因等位，Ne基因可抑制由其栽培番茄等位基因ne（坏死）所引发的Cf-2依赖性自身坏死。这两个物种的Rcr3等位基因所编码的蛋白质仅相差七个氨基酸。本文讨论了Rcr3在Cf-2依赖性防御和自身坏死中的可能作用。
