Pm21 from Haynaldia villosa Encodes a CC-NBS-LRR Protein Conferring Powdery Mildew Resistance in Wheat
Pm21 from Haynaldia villosa Encodes a CC-NBS-LRR Protein Conferring Powdery Mildew Resistance in Wheat
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Haynaldia villosa 的 Pm21 编码 CC-NBS-LRR 蛋白，赋予小麦抗白粉病性
DOI：
10.1016/j.molp.2018.02.013
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发表时间：
2018-06-04
期刊：
影响因子：
27.5
通讯作者：
Cao, Aizhong
中科院分区：
文献类型：
--
作者：
Xing, Liping;Hu, Ping;Cao, Aizhong
小麦白粉病是由小麦白粉病菌Blumeria graminis f.小麦赤霉病（Bgt）是世界性的小麦毁灭性病害。减少由Bgt引起的小麦损失的最重要的环境友好和经济的方法之一是开发高度抗性品种（Kuraparthy等人，2007年）。来自野生种簇毛麦（也称为簇毛麦）的Pm 21在小麦的所有生长阶段赋予对Bgt的高抗性。Pm21基因已成为从野生种渗入小麦中最有效的遗传位点之一，目前我国已推广种植了400多万hm 2的小麦品种，由于外源染色体的重组抑制，细胞遗传学的发展使Pm 21的物理位置逐渐缩小，包含染色体区域和候选基因的鉴定。全臂易位系T6 VS $6 AL的开发导致6VS臂上的Pm 21基因座的鉴定（Chen et al.，1995年），之后开发的抗性缺失股票del。6VS-1（片段长度[FL] 0.58）和易感缺失原种del. 6VS-2（FL 0.45）随后导致其染色体区域从FL 0.45至FL 0.58的定位（Cao等人，2011年）。涉及6VS的小片段的两个易位系NAU 418和NAU 419的开发随后导致Pm21到分子标记CINAU 273和CINAU 276之间的染色体区域的定义（Chen等人，2013年）。我们先前鉴定了Stpk-V基因作为Pm21基因座的关键成员;该基因位于6VS FL 0.45-FL 0.58区域，并且也位于NAU 418和NAU 419中的渐渗片段中。Stpk-V的过表达导致对白粉病的广谱抗性增强，而Stpk-V沉默显著但不完全损害T6 VS $6 AL的抗性（Cao等人，2011年）。利用基因组原位杂交（GISH）技术在已有的细胞遗传学材料中鉴定出的外源基因片段太大，不适合于Pm21基因的定位，而且在克隆该外源基因的整个过程中，既缺乏参考数据，又缺乏功能丧失突变体，限制了对该基因的遗传学研究。因此，Pm21基因位点上的基因簇是否有助于白粉病抗性仍然是未知的。在这项研究中，综合的方法，包括细胞遗传学股票开发，诱变，抗性基因富集和测序（RenSeq）-PacBio，远程组装，和功能分析，随后被用来成功克隆Pm21基因。
Wheat powdery mildew, caused by Blumeria graminis f. sp. tritici (Bgt), is a destructive disease of wheat throughout the world. One of the most important environmental-friendly and economical methods to reduce wheat loss caused by Bgt is to develop highly resistant varieties (Kuraparthy et al., 2007). Pm21 from the wild species Haynaldia villosa (also known as Dasypyrum villosum) confers high resistance to Bgt in wheat throughout all growth stages. It has now become one of the most highly effective genetic loci introgressed into wheat from wild species, and the commercial varieties harboring Pm21 have been widely used in wheat production with more than 4 million hectares in China.Owing to the recombination inhibition of alien chromosomes, the development of cytogenetic stocks has allowed the gradual narrowing of the physical location of the Pm21-containing chromosomal region and the identification of candidate genes. Development of the whole-arm translocation line T6VS $6 AL led to the identification of the Pm21 locus on the 6VS arm (Chen et al., 1995), after which development of the resistant deletion stock del. 6VS-1 (fraction length [FL] 0.58) and susceptible deletion stock del. 6VS-2 (FL 0.45) subsequently resulted in the location of its chromosome region from FL 0.45 to FL 0.58 (Cao et al., 2011). The development of two translocation lines, NAU418 and NAU419, which involves small segments of 6VS, then resulted in the definition of Pm21 to chromosomal region between molecular markers CINAU273 and CINAU276 (Chen et al., 2013). We previously identified the Stpk-V gene as a key member of Pm21 gene locus; this gene was located in the 6VS FL 0.45-FL 0.58 region and also in the introgressed segment in NAU418 and NAU419. Overexpression of Stpk-V resulted in enhanced broad-spectrum resistance to powdery mildew, while Stpk-V silencing significantly but not completely compromised the resistance of T6VS $6 AL (Cao et al., 2011). The alien segment identified by genomic in situ hybridization (GISH) in the previous cytogenetic stocks was too large for mapping Pm21 gene; moreover, a lack of both reference data and lossof-function mutants throughout the process of cloning this alien gene has limited its genetic elucidation. Therefore, whether a cluster of genes at the Pm21 gene locus contribute to the powdery mildew resistance remains unknown. In this study, comprehensive approaches including cytogenetic stock development, mutagenesis, resistance gene enrichment and sequencing (RenSeq)-PacBio, long-range assembly, and functional analysis were subsequently used to successfully clone the Pm21 gene.