PLOS Genetics ( IF 4.5 ) Pub Date : 2020-11-11 , DOI: 10.1371/journal.pgen.1009114 Hengyou Zhang , Wolfgang Goettel , Qijian Song , He Jiang , Zhenbin Hu , Ming Li Wang , Yong-qiang Charles An
Soybean [Glycine max (L.) Merr.] was domesticated from wild soybean (G. soja Sieb. and Zucc.) and has been further improved as a dual-use seed crop to provide highly valuable oil and protein for food, feed, and industrial applications. However, the underlying genetic and molecular basis remains less understood. Having combined high-confidence bi-parental linkage mapping with high-resolution association analysis based on 631 whole sequenced genomes, we mapped major soybean protein and oil QTLs on chromosome15 to a sugar transporter gene (GmSWEET39). A two-nucleotide CC deletion truncating C-terminus of GmSWEET39 was strongly associated with high seed oil and low seed protein, suggesting its pleiotropic effect on protein and oil content. GmSWEET39 was predominantly expressed in parenchyma and integument of the seed coat, and likely regulates oil and protein accumulation by affecting sugar delivery from maternal seed coat to the filial embryo. We demonstrated that GmSWEET39 has a dual function for both oil and protein improvement and undergoes two different paths of artificial selection. A CC deletion (CC-) haplotype H1 has been intensively selected during domestication and extensively used in soybean improvement worldwide. H1 is fixed in North American soybean cultivars. The protein-favored (CC+) haplotype H3 still undergoes ongoing selection, reflecting its sustainable role for soybean protein improvement. The comprehensive knowledge on the molecular basis underlying the major QTL and GmSWEET39 haplotypes associated with soybean improvement would be valuable to design new strategies for soybean seed quality improvement using molecular breeding and biotechnological approaches.
中文翻译:
GmSWEET39在大豆油和蛋白质改良中的双重用途和选择
大豆[大豆(L.)MERR。]从野生大豆(驯化ģ。大豆SIEB。和山茱萸。),并已作为两用种子作物得到进一步的提高,为食品提供非常有价值的油和蛋白质,饲料,和工业应用。然而,潜在的遗传和分子基础仍然知之甚少。将高可信度的双亲连锁映射与基于631个完整测序基因组的高分辨率关联分析相结合,我们将15号染色体上的主要大豆蛋白和油QTL定位到糖转运蛋白基因(GmSWEET39)。截断GmSWEET39 C端的两个核苷酸CC缺失与高籽油和低籽蛋白密切相关,表明其对蛋白质和油含量的多效性。GmSWEET39主要在种皮的薄壁组织和外被中表达,并可能通过影响糖从母体种皮到孝子胚的传递来调节油和蛋白质的积累。我们证明了GmSWEET39具有改善油脂和蛋白质的双重功能,并经历两种不同的人工选择路径。在驯化过程中已密集选择了CC缺失(CC-)单倍型H1,并已广泛用于全世界的大豆改良中。H1在北美大豆品种中固定。蛋白质偏爱(CC +)单倍型H3仍在进行选择,反映了其对大豆蛋白质改良的可持续作用。有关与大豆改良有关的主要QTL和GmSWEET39单倍型的分子基础的全面知识,对于设计使用分子育种和生物技术方法改善大豆种子品质的新策略将具有重要的价值。