Lang Jing, Jiang Huayu, Cheng Mengping, Wang Mingwei, Gu Jing, Dong Huixue, Li Maolian, Guo XiaoJiang, Chen Qian, Wang Jirui
State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu, 611130, China.
College of Agronomy, Sichuan Agricultural University, Chengdu, 611130, China.
Plant J. 2024 Jun;118(5):1388-1399. doi: 10.1111/tpj.16676. Epub 2024 Feb 26.
Pre-harvest sprouting (PHS) is a significant threat to global food security due to its association with losses in both yield and quality. Among the genes involved in PHS resistance in wheat, PHS-3D (TaMyb10-D) plays a crucial role. Here, we characterized the sequence variations of TaMyb10 genes in 416 bread wheat and 302 Aegilops tauschii accessions. Within TaMyb10-A sequences, we identified a deletion ranging from 214 to 305 bp in the signal and amino acid coding region, present in 61.3% of the accessions. Similarly, 79.3% of the TaMyb10-B sequences within the third exon region exhibited a 19 bp deletion. Additionally, 40.8% of the accessions lacked the 2.4 Mb fragment (in/del mutations) on Chr3D, where TaMyb10-D/PHS-3D was located. Interestingly, the geographical distribution of accessions showed little correlation with the divergence of TaMyb10. TaMyb10-A-III, TaMyb10-B-IV, and TaMyb10-D-V genotypes were prevalent in wheat populations across continents. Despite their structural variations, the five distinct protein types exhibited comparable ability to bind the promoters of downstream genes in the flavonoid and ABA pathways, such as CHS, DFR, and NCED. Furthermore, the combination of TaMyb10 homologs was significantly associated with grain color and germination percentages. Accessions exclusively harboring TaMyb10-D displayed red seed color and reduced germination percentages, indicating the predominant role of TaMyb10-D compared to TaMyb10-A and TaMyb10-B. This comprehensive investigation enhances our understanding of the structural variations and functional divergence of TaMyb10, providing valuable insights and resources for improving PHS resistance in wheat.
收获前发芽（PHS）与产量和品质损失相关，对全球粮食安全构成重大威胁。在参与小麦抗收获前发芽的基因中，PHS-3D（TaMyb10-D）起着关键作用。在此，我们对416份面包小麦和302份节节麦材料中的TaMyb10基因序列变异进行了表征。在TaMyb10-A序列中，我们在信号和氨基酸编码区域鉴定出一个214至305 bp的缺失，存在于61.3%的材料中。同样，第三外显子区域内79.3%的TaMyb10-B序列表现出19 bp的缺失。此外，40.8%的材料在TaMyb10-D/PHS-3D所在的3D染色体上缺少2.4 Mb片段（插入/缺失突变）。有趣的是，材料的地理分布与TaMyb10的差异几乎没有相关性。TaMyb10-A-III、TaMyb10-B-IV和TaMyb10-D-V基因型在各大洲的小麦群体中普遍存在。尽管它们存在结构变异，但这五种不同的蛋白质类型在结合类黄酮和脱落酸途径中下游基因（如CHS、DFR和NCED）的启动子方面表现出相当的能力。此外，TaMyb10同源物的组合与籽粒颜色和发芽率显著相关。仅含有TaMyb10-D的材料表现出红色种子颜色和降低的发芽率，表明与TaMyb10-A和TaMyb10-B相比，TaMyb10-D起主要作用。这项全面的研究增进了我们对TaMyb10结构变异和功能差异的理解，为提高小麦抗收获前发芽能力提供了有价值的见解和资源。
