小麦广谱抗条锈病基因Yr15的互作蛋白分析

Stripe rust, caused by Puccinia striiformis f. sp.tritici (Pst), is a devastating fungal disease that threatens wheat production worldwide. The Yr15, derived from wild emmer wheat, provides broad-spectrum and all-stage protection against Pst races thus is important for wheat resistance breeding. In our previous work, we have identified this gene through positional cloning. However, the underlying molecular resistance mechanism has been unclear. In the present study, we will screen the interacting proteins of Yr15 using yeast two-hybrid system, and confirm the interaction through pull-down assay and bimolecular fluorescence complementation. We will select one target protein to perform functional analysis through quantitative real-time PCR, phosphorylation assays, histochemical stain, and virus induced gene silencing (VIGS). We expect that our works will make the pavement for revealing the resistance mechanism of Yr15.

小麦条锈病是威胁小麦生产的重要真菌病害。Yr15是来源于野生二粒小麦的一个广谱抗条锈病基因，为小麦全生育期提供完全抗性，具有重要的育种应用价值。前期工作中，我们通过图位克隆得到了Yr15的基因序列，但它的抗病分子机理还不清楚。本研究利用酵母双杂交、pull-down和双分子荧光互补分析相结合的方法，筛选并获得Yr15互作蛋白；利用基因定量表达、蛋白磷酸化分析、组织化学染色、基因瞬时沉默等方法对关键互作蛋白进行功能分析，为深入解析Yr15的抗性分子机理提供重要基础。

野生二粒小麦广谱抗条锈病基因Yr15编码串联激酶结构域蛋白，具有重要的抗病育种应用价值，但它的广谱抗性分子机理尚不清楚。本项目利用酵母双杂交技术，筛库获得5个与Yr15互作的蛋白（WRKY、MYB、TIFY、PRK和ToxAB）。选取其中两个互作蛋白（ToxAB和WRKY）分别进行互作关系验证，并利用表达特性分析、VIGS瞬时沉默和组织化学观察等对互作基因进行初步功能分析，证实ToxAB和WRKY可能参与了对Yr15介导的条锈病抗性调控；进一步结合转录组、单倍型分析，表明能量代谢和病原防御相关基因参与了Yr15介导的条锈病抗性，Yr15可能通过与病原菌的间接识别实现广谱抗性。本研究初步揭示Yr15广谱持久抗性机理，对加快Yr15的抗病育种利用，实现小麦条锈病持续有效防治具有重要意义。