The Stripe Rust Resistance Gene Yr10 Encodes an Evolutionary-Conserved and Unique CC-NBS-LRR Sequence in Wheat
The Stripe Rust Resistance Gene Yr10 Encodes an Evolutionary-Conserved and Unique CC-NBS-LRR Sequence in Wheat
复制标题
DOI：
10.1093/mp/ssu112
复制
发表时间：
2014-12-01
期刊：
影响因子：
27.5
通讯作者：
Laroche, Andre
中科院分区：
文献类型：
--
作者：
Liu, Wei;Frick, Michele;Laroche, Andre
首次从Moro小麦(Triticum aestivum L.)中分离到抗条锈病(R)基因。使用基于地图的克隆方法被确定为Yr10。该基因的4B克隆编码一个高度进化保守且独特的CC-NBS-LRR序列。克隆4E是Yr10的同源基因，但缺少转录起始位点(TSS)和推测的TATA-box和CAAT-box，可能是一个未表达的假基因。克隆4B和4E在内含子和LRR结构域上有84%的同源性和差异性。基因沉默和转基因结合接种不同毒力和不同毒力的条锈菌菌株来证明Yr10的功能。Yr10CC-NBS-LRR序列在已知的小麦CC-NBS-LRR R基因中是独一无二的，但在节节麦和其他单子叶植物中发现了高度保守的同源物(E=0.0)。在玉米、水稻和高粱的基因组数据库中也发现了相关序列。这是首次报道了CC-NBS-LRR抗性基因在其自然寄主中同源性有限的植物中，但在作为条锈病宿主或非寄主的相关单子叶中具有大量同源R基因的植物中的首次报道。这些结果代表了基因进化和跨物种扩散的一个独特例子。
The first seedling or all-stage resistance (R) R gene against stripe rust isolated from Moro wheat (Triticum aestivum L.) using a map-based cloning approach was identified as Yr10. Clone 4B of this gene encodes a highly evolutionary-conserved and unique CC-NBS-LRR sequence. Clone 4E, a homolog of Yr10, but lacking transcription start site (TSS) and putative TATA-box and CAAT-box, is likely a non-expressed pseudogene. Clones 4B and 4E are 84% identical and divergent in the intron and the LRR domain. Gene silencing and transgenesis were used in conjunction with inoculation with differentially avirulent and virulent stripe rust strains to demonstrate Yr10 functionality. The Yr10 CC-NBS-LRR sequence is unique among known CC-NBS-LRR R genes in wheat but highly conserved homologs (E = 0.0) were identified in Aegilops tauschii and other monocots including Hordeum vulgare and Brachypodium distachyon. Related sequences were also identified in genomic databases of maize, rice, and in sorghum. This is the first report of a CC-NBS-LRR resistance gene in plants with limited homologies in its native host, but with numerous homologous R genes in related monocots that are either host or non-hosts for stripe rust. These results represent a unique example of gene evolution and dispersion across species.