Identification of regions in alleles of the flax rust resistance gene L that determine differences in gene-for-gene specificity
Identification of regions in alleles of the flax rust resistance gene L that determine differences in gene-for-gene specificity
复制标题
DOI：
10.1105/tpc.11.3.495
复制
发表时间：
1999-03-01
期刊：
影响因子：
11.6
通讯作者：
Dodds, PN
中科院分区：
文献类型：
--
作者：
Ellis, JG;Lawrence, GJ;Dodds, PN
13个等位基因（L，L1至L11，LH）从亚麻L基因座，编码Toll/白细胞介素-1受体同源性-核苷酸结合位点-亮氨酸丰富的重复序列（TIR-NBS-LRR）锈病抗性蛋白，进行测序和比较，以了解它们的进化和基因对基因抗性特异性的决定因素。预测的L 6和L11蛋白仅在LRR区域不同，而L 6和L7仅在TIR区域不同。因此，等位基因之间的特异性差异可以通过LRR和TIR区域两者来确定。对体外构建的重组等位基因在转基因植物中的功能分析提供了进一步的信息：编码L2的LRR的L10-L2和L 6-L2重组体赋予L2抗性特异性，并且编码L10的LRR的L2-L10重组体赋予新的特异性。序列比较还表明，L等位基因的进化可能涉及变异的重配，导致积累的点突变，通过基因内重组。此外，大的缺失事件发生在L1和L 8的LRR编码区，和重复事件发生在L2的LRR编码区。
Thirteen alleles (L, L1 to L11, and LH) from the flax L locus, which encode Toll/interleukin-1 receptor homology-nucleotide binding site-leucine-rich repeat (TIR-NBS-LRR) rust resistance proteins, were sequenced and compared to provide insight into their evolution and into the determinants of gene-for-gene resistance specificity. The predicted L6 and L11 proteins differ solely in the LRR region, whereas L6 and L7 differ solely in the TIR region. Thus, specificity differences between alleles can be determined by both the LRR and TIR regions. Functional analysis in transgenic plants of recombinant alleles constructed in vitro provided further information: L10-L2 and L6-L2 recombinants, encoding the LRR of L2, conferred L2 resistance specificity, and an L2-L10 recombinant, encoding the LRR of L10, conferred a novel specificity. The sequence comparisons also indicate that the evolution of L alleles has probably involved reassortment of variation, resulting from accumulated point mutations, by intragenic recombination, In addition, large deletion events have occurred in the LRR-encoding regions of L1 and L8, and duplication events have occurred in the LRR-encoding region of L2.