Stem rust resistance in wheat is suppressed by a subunit of the mediator complex
Stem rust resistance in wheat is suppressed by a subunit of the mediator complex
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DOI：
10.1038/s41467-020-14937-2
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发表时间：
2020-02-28
影响因子：
16.6
通讯作者：
Spielmeyer, Wolfgang
中科院分区：
文献类型：
--
作者：
Hiebert, Colin W.;Moscou, Matthew J.;Spielmeyer, Wolfgang
小麦秆锈病是小麦的重要病害，利用抗病基因可以有效地控制秆锈病。在品种‘Canthatch’中鉴定的基因SuSr-D1抑制茎锈病抗性。SuSr-D1突变体对几种在野生型植物上有毒的茎锈病具有抗性。在这里，我们确定SuSr-D1测序流式分选染色体，诱变，图位克隆。该基因编码Med 15，Med 15是介体复合物的亚基，介体复合物是真核生物中调节蛋白质编码基因表达的保守蛋白质复合物。Med15b.D中的无义突变导致茎锈病抗性的表达。时间过程RNAseq分析显示，在med15b.D突变体中，在接种后24小时差异基因表达显著减少或完全丧失，这表明在该时间点的转录重编程对于对茎锈病的免疫力不是必需的。抑制是一种普遍现象，本研究为小麦抗锈性抑制提供了新的见解。秆锈病是小麦的一种重要病害，SuSr-D1位点可以抑制部分小麦品种的抗病性。在这里，作者表明SuSr-D1编码介体复合物的一个亚基，并且无义突变足以消除抑制并赋予茎锈病抗性。
Stem rust is an important disease of wheat that can be controlled using resistance genes. The gene SuSr-D1 identified in cultivar 'Canthatch' suppresses stem rust resistance. SuSr-D1 mutants are resistant to several races of stem rust that are virulent on wild-type plants. Here we identify SuSr-D1 by sequencing flow-sorted chromosomes, mutagenesis, and map-based cloning. The gene encodes Med15, a subunit of the Mediator Complex, a conserved protein complex in eukaryotes that regulates expression of protein-coding genes. Nonsense mutations in Med15b.D result in expression of stem rust resistance. Time-course RNAseq analysis show a significant reduction or complete loss of differential gene expression at 24h post inoculation in med15b.D mutants, suggesting that transcriptional reprogramming at this time point is not required for immunity to stem rust. Suppression is a common phenomenon and this study provides novel insight into suppression of rust resistance in wheat. Stem rust is an important disease of wheat and resistance present in some cultivars can be suppressed by the SuSr-D1 locus. Here the authors show that SuSr-D1 encodes a subunit of the Mediator Complex and that nonsense mutations are sufficient to abolish suppression and confer stem rust resistance.