Fine-Mapping and Functional Analyses of a Candidate Gene Controlling Isoflavone Content in Soybeans Seed.

Isoflavones, one of the most important secondary metabolites produced by soybeans ( (L.) Merr.), are important for a variety of biological processes, and are beneficial for human health. To identify genetic loci underlying soybean isoflavone content, a mapping population containing 119 F recombinant inbred lines, derived by crossing soybean cultivar "Zhongdou27" with "Dongong8004," was used. We identified 15 QTLs associated with isoflavone contents. A novel loci, qISO19-1, was mapped onto soybean chromosome 19 and was fine-mapped to a 62.8 kb region using a BCF population. We considered as a candidate gene for the qISO19-1 locus due to the significant positive correlation recovered between its expression level and isoflavone content in the seeds of 43 soybean germplasms. Overexpression of in and soybean cultivars increased isoflavone contents. Transgenic soybeans overexpressing also exhibited improved resistance to pathogenic infection, while transgenic resisted salt and drought stress.