Sequence variation at the rice blast resistance gene Pi-km locus: Implications for the development of allele specific markers
Sequence variation at the rice blast resistance gene Pi-km locus: Implications for the development of allele specific markers
复制标题
DOI：
10.1016/j.plantsci.2010.02.014
复制
发表时间：
2010-06-01
期刊：
影响因子：
5.2
通讯作者：
Jia, Yulin
中科院分区：
文献类型：
--
作者：
Costanzo, Stefano;Jia, Yulin
最近克隆的抗稻瘟病基因Pi-km以基因对基因的方式保护水稻作物免受稻瘟病病菌的侵害。使用原细胞R基因仍然是综合疾病管理策略中最具成本效益的方法。为了方便水稻育种，我们开发了Pi-km特异性DNA标记。为此，我们初步探索了Pi-km特异性的两个基因等位基因的现有序列多样性。对15个水稻品种的分析表明，大部分核苷酸多态性与Pi-km 1基因有关。有趣的是，相应的氨基酸变异定位在假定的Pi-km1蛋白的预测卷曲结构域内。相比之下，Pi-krn2等位基因序列即使在远亲品种中也是高度保守的。此外，所选品种对5个米曲菌分离株的疾病反应及其测定的Pi-km等位基因与这些品种已知的Pi-k基因（-k/-kh/-km/-ks/-kp）具有良好的相关性。基于这些发现，设计了特定的引物集来区分不同的Pi-km等位基因。这些新标记将简化与复杂Pi-k位点相关的有价值的稻瘟病抗性向水稻品种的渗入。Elsevier Ltd.出版。
The recently cloned blast resistance (R) gene Pi-km protects rice crops against specific races of the fungal pathogen Magnaporthe oryzae in a gene-for-gene manner. The use of blast R genes remains the most cost-effective method for an integrated disease management strategy. To facilitate rice breeding we developed a Pi-km specific DNA marker. For this purpose, we initially explored the existing sequence diversity for alleles of the two genes responsible for the Pi-km specificity. The analysis of 15 rice cultivars revealed that the majority of nucleotide polymorphisms were associated with the Pi-km 1 gene. Interestingly, the correspondent amino acid variation was localized within the predicted coiled-coil domain of the putative Pi-km1 protein. In contrast, the sequence of Pi-krn2 alleles was highly conserved even within distantly related cultivars. Furthermore, disease reactions of the selected cultivars to five M. oryzae isolates, as well as their determined Pi-km] allele, showed a good correlation with the known Pi-k genes (-k/-kh/-km/-ks/-kp) historically reported for these cultivars. Based on these findings, specific primer sets have been designed to discriminate among the various Pi-km alleles. The new markers should simplify the introgression of the valuable blast resistance associated with the complex Pi-k locus into rice cultivars. Published by Elsevier Ltd.