The L6 and M rust-resistance genes, representing two of the five rust-resistance gene loci in flax (Linum usitatissimum), have been cloned. The molecular data are fully consistent with earlier genetic data: the L locus is a single gene with multiple alleles expressing different rust resistance specificities, and the M locus is complex, containing an array of about 15 similar genes. Thus, while L6 and M resistance genes have 86% nucleotide identity, their locus structure is very different. These genes encode products belonging to the nucleotide binding site-leucine-rich repeat class of disease-resistance proteins. Analysis of alleles from the L locus and chimeric genes is providing evidence suggesting that important specificity determinants occur in the C-terminal half of the proteins, the region containing the leucine-rich repeats. The isolation and characterization of the rust (Melampsora lini) avirulence genes that correspond to the cloned rust-resistance genes is one of the major challenges remaining to the understanding of this system.

中文翻译：

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亚麻-亚麻锈相互作用的分子遗传学研究进展。

已克隆了代表亚麻（Linum usitatissimum）中五个防锈基因位点中的两个的L6和M防锈基因。分子数据与早期遗传数据完全一致：L基因座是一个具有多个等位基因的单一基因，其表达不同的抗锈性特异性，而M基因座是复杂的，包含约15个相似基因。因此，尽管L6和M抗性基因具有86％的核苷酸同一性，但它们的基因座结构却非常不同。这些基因编码的产物属于抗病蛋白的核苷酸结合位点-富含亮氨酸的重复序列。对来自L基因座和嵌合基因的等位基因的分析提供了证据，表明重要的特异性决定簇出现在蛋白质的C末端一半，即富含亮氨酸重复序列的区域。