PDF(Pubmed)
Abstract：
Many disease resistance genes have been introgressed into wheat from its wild relatives. However, reduced recombination within the introgressed segments hinders the cloning of the introgressed genes. Here, we have cloned the powdery mildew resistance gene Pm13, which is introgressed into wheat from Aegilops longissima, using a method that combines physical mapping with radiation-induced chromosomal aberrations and transcriptome sequencing analysis of ethyl methanesulfonate (EMS)-induced loss-of-function mutants. Pm13 encodes a kinase fusion protein, designated MLKL-K, with an N-terminal domain of mixed lineage kinase domain-like protein (MLKL_NTD domain) and a C-terminal serine/threonine kinase domain bridged by a brace. The resistance function of Pm13 is validated through transient and stable transgenic complementation assays. Transient over-expression analyses in Nicotiana benthamiana leaves and wheat protoplasts reveal that the fragment Brace-Kinase122-476 of MLKL-K is capable of inducing cell death, which is dependent on a functional kinase domain and the three α-helices in the brace region close to the N-terminus of the kinase domain.
摘要：
许多抗病基因已从其野生近缘种渗入小麦。然而,渗入片段内重组的减少阻碍了渗入基因的克隆。这里,我们已经克隆了抗白粉病基因Pm13，该基因从Aegilopslongissima渗入小麦中，使用将物理作图与辐射诱导的染色体畸变和甲磺酸乙酯（EMS）诱导的功能丧失突变体的转录组测序分析相结合的方法。Pm13编码激酶融合蛋白，指定MLKL-K,具有混合谱系激酶结构域样蛋白的N末端结构域（MLKL_NTD结构域）和通过支架桥接的C末端丝氨酸/苏氨酸激酶结构域。通过瞬时和稳定的转基因互补试验验证了Pm13的抗性功能。Nicotianabenthamiana叶片和小麦原生质体中的瞬时过表达分析表明，MLKL-K的Brace-Kinase122-476片段能够诱导细胞死亡，它依赖于功能性激酶结构域和靠近激酶结构域N末端的大括号区域中的三个α螺旋。
