Genetic studies of the flax-flax rust interaction led to the formulation of the gene-for-gene hypothesis and identified resistance genes (R) in the host plant and pathogenicity genes, including avirulence (Avr) and inhibitor of avirulence genes (I), in the rust pathogen. R genes have now been cloned from four of the five loci in flax and all encode proteins of the Toll, Interleukin-1 receptor, R gene-nucleotide binding site-leucine-rich repeat (TIR-NBS-LRR) class. Avr genes have been cloned from four loci in flax rust and encode small secreted proteins with no between locus similarity and no close homologs in current data bases. It is postulated that Avr proteins enter the host cell, have virulence effector functions, and in resistant host genotypes, are recognized by direct and specific interaction with host R proteins, leading to activation of rust resistance defense responses. Direct interaction between R and Avr proteins is the basis of gene-for-gene specificity in the flax-flax rust system and both R and Avr genes have the signatures of diversifying selection, suggesting the existence of a coevolutionary arms race between the host plant and its obligate rust pathogen.

中文翻译：

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亚麻锈病抗性基因特异性基于直接的抗性-毒力蛋白相互作用。

亚麻-亚麻锈相互作用的遗传研究导致了基因对基因假说的提出，并确定了宿主植物中的抗性基因（R）和致病性基因，包括无毒力（Avr）和无毒力基因的抑制剂（I），在锈病病原体中。现在已经从亚麻五个位点中的四个位点克隆了R基因，并且所有编码Toll，Interleukin-1受体，R基因-核苷酸结合位点-富含亮氨酸的重复序列（TIR-NBS-LRR）的蛋白质。已从亚麻锈病的四个基因座中克隆了Avr基因，并编码小分泌的蛋白质，在当前数据库中，基因座之间没有相似性且同源性也不高。据推测，Avr蛋白进入宿主细胞，具有毒力效应子功能，并在抗性宿主基因型中被与宿主R蛋白的直接和特异性相互作用所识别，导致防锈防御反应的激活。R和Avr蛋白之间的直接相互作用是亚麻-亚麻锈系统中基因对基因特异性的基础，R和Avr基因都具有多样化选择的特征，这表明宿主植物与植物之间存在着共同进化的军备竞赛。其专一的锈病病原体。