背景+问题：The role of abscisic acid (ABA) receptors, PYR1/PYL/RCAR (PYLs), is well established in ABA signaling and plant drought response, but limited research has explored the regulation of wheat PYLs in this process, especially the effects of their allelic variations on drought tolerance or grain yield. 

主要发现：Here, we found that overexpression of a TaABFs-regulated PYL gene, TaPYL1-1B, exhibited higher ABA sensitivity, photosynthetic capacity, and water-use efficiency (WUE), all contributed to higher drought tolerance than that of wild-type plants. 

结果1-缺水条件下保证产量：This heightened water-saving mechanism further increased grain yield and protected productivity during water deficit. 

结果2-关键等位基因变异：Candidate gene association analysis revealed that a favorable allele TaPYL1-1BIn-442, carrying an MYB recognition site insertion in the promoter, is targeted by TaMYB70 and confers enhanced expression of TaPYL1-1B in drought-tolerant genotypes. 

结果3-改良育种与人工选择：More importantly, an increase in frequency of the TaPYL1-1BIn-442 allele over decades among modern Chinese cultivars and its association with high thousand-kernel weight together demonstrated that it was artificially selected during wheat improvement efforts. 

结论：Taken together, our findings illuminate the role of TaPYL1-1B plays in coordinating drought tolerance and grain yield. In particular, the allelic variant TaPYL1-1BIn-442 substantially contributes to enhanced drought tolerance while maintaining high yield, and thus represents a valuable genetic target for engineering drought-tolerant wheat germplasm.

 摘 要 

脱落酸ABA的受体PYLs作用于ABA信号转导和植物的干旱响应，但是小麦PYLs的调控机制却所知甚少，尤其是其等位基因变异对于干旱耐受性或者籽粒产量方面的影响。本文中，作者发现过表达一个TaABFs调控的PYL基因TaPYL1-1B，相比于野生型增加了ABA的敏感性、光合能力以及水分利用效率，最终作用于更强的干旱耐受性。这种增强型的节水机制进一步提升了粮食产量，并在缺水期间保证了作物产量。候选基因关联分析显示TaPYL1-1BIn-442是最佳等位基因，其启动子区域包含一段含有MYB识别位点的插入序列，受到TaMYB70的靶向，从而赋予了干旱耐受性基因型更高的TaPYL1-1B基因表达。更加重要的是，数十年间现代中国栽培种中TaPYL1-1BIn-442等位基因的频率有所增加，并且其与高水平的千粒重相关，说明该等位基因在小麦改良过程中受到了人工选择。综上，本文的研究阐释了TaPYL1-1B基因做用于干旱抗性和籽粒产量方面的作用。尤其是，TaPYL1-1BIn-442等位基因变体在维持高产的情况下，极大地作用于干旱抗性的增强，因此可以作为未来小麦种质干旱抗性育种的潜在遗传靶标。

 通讯作者 

** 康振生 **