Physical Mapping of Pm57, a Powdery Mildew Resistance Gene Derived from Aegilops searsii
Physical Mapping of Pm57, a Powdery Mildew Resistance Gene Derived from Aegilops searsii
复制标题
西山羊草抗白粉病基因Pm57的物理图谱
DOI：
10.3390/ijms21010322
复制
发表时间：
2020-01-01
影响因子：
5.6
通讯作者：
Liu, Wenxuan
中科院分区：
文献类型：
--
作者：
Dong, Zhenjie;Tian, Xiubin;Liu, Wenxuan
小麦白粉病是由小麦白粉病菌Blumeria graminis f.小麦赤霉病（Triticum aestivum L.）世界范围内的产量和质量。小麦抗白粉病基因的发现和利用，可以有效地控制小麦白粉病的流行。在前期的研究中，我们将来自于斯氏山羊草的抗白粉病基因Pm 57转入普通小麦，并将该基因定位在染色体2S（s）#1长臂的12%片段上，其片段长度（FL）为0.75-0.87。在这项研究中，我们使用从三个感染和模拟感染的小麦-Ae的叶片样品中提取的RNA进行RNA-seq。searsii 2S（s）#1渐渗系在接种Bgt分离物后0、12、24和48 h时的抗性。然后我们根据转录组序列设计了79个分子标记，并将它们物理定位到Ae。searsii染色体2S（s）#1-在七个间隔。利用这些标记对46个小麦品种进行了鉴定。searsii 2S（s）#1重组子，该重组子是由一个配对同源（Ph）基因的缺失突变体ph 1b诱导的。在分析了46个phlb诱导的2S（s）#1L重组体在Pm 57所在区域的不同Bgt反应后，我们将Pm 57基因物理定位在2S（s）#1的长臂上的5.13 Mb基因组区域中，该区域两侧是标记X67593（773.72 Mb）和X62492（778.85 Mb）。通过对中国春2B染色体上相应区域的比较同线性分析，通过与其他模式物种的比较，我们鉴定了10个植物防御相关基因，包括6个卷曲螺旋核苷酸结合位点--富含亮氨酸重复序列（CNL）、3个核苷酸结合位点--富含亮氨酸重复序列（NL）和1个富含亮氨酸受体样重复序列（RLP）编码蛋白。本研究为Pm 57基因的克隆奠定了基础，也为进一步研究小麦抗白粉病基因与白粉病病原菌的互作关系奠定了基础。
Powdery mildew caused by Blumeria graminis f. sp. tritici (Bgt) is one of many severe diseases that threaten bread wheat (Triticum aestivum L.) yield and quality worldwide. The discovery and deployment of powdery mildew resistance genes (Pm) can prevent this disease epidemic in wheat. In a previous study, we transferred the powdery mildew resistance gene Pm57 from Aegilops searsii into common wheat and cytogenetically mapped the gene in a chromosome region with the fraction length (FL) 0.75-0.87, which represents 12% segment of the long arm of chromosome 2S(s)#1. In this study, we performed RNA-seq using RNA extracted from leaf samples of three infected and mock-infected wheat-Ae. searsii 2S(s)#1 introgression lines at 0, 12, 24, and 48 h after inoculation with Bgt isolates. Then we designed 79 molecular markers based on transcriptome sequences and physically mapped them to Ae. searsii chromosome 2S(s)#1- in seven intervals. We used these markers to identify 46 wheat-Ae. searsii 2S(s)#1 recombinants induced by ph1b, a deletion mutant of pairing homologous (Ph) genes. After analyzing the 46 ph1b-induced 2S(s)#1L recombinants in the region where Pm57 is located with different Bgt-responses, we physically mapped Pm57 gene on the long arm of 2S(s)#1 in a 5.13 Mb genomic region, which was flanked by markers X67593 (773.72 Mb) and X62492 (778.85 Mb). By comparative synteny analysis of the corresponding region on chromosome 2B in Chinese Spring (T.aestivum L.) with other model species, we identified ten genes that are putative plant defense-related (R) genes which includes six coiled-coil nucleotide-binding site-leucine-rich repeat (CNL), three nucleotide-binding site-leucine-rich repeat (NL) and a leucine-rich receptor-like repeat (RLP) encoding proteins. This study will lay a foundation for cloning of Pm57, and benefit the understanding of interactions between resistance genes of wheat and powdery mildew pathogens.