A genome-wide association study of folates in sweet corn kernels

Yingni Xiao; Yongtao Yu; Lihua Xie; Kun Li; Xinbo Guo; Guangyu Li; Jianhua Liu; Gaoke Li; Jianguang Hu

doi:10.3389/fpls.2022.1004455

A genome-wide association study of folates in sweet corn kernels

Front Plant Sci. 2022 Sep 30:13:1004455. doi: 10.3389/fpls.2022.1004455. eCollection 2022.

Authors

Yingni Xiao¹, Yongtao Yu¹, Lihua Xie¹, Kun Li¹, Xinbo Guo², Guangyu Li¹, Jianhua Liu¹, Gaoke Li¹, Jianguang Hu¹

Affiliations

¹ Crops Research Institute, Guangdong Academy of Agricultural Sciences/Guangdong Provincial Key Laboratory of Crop Genetic Improvement, Guangzhou, China.
² School of Food Science and Engineering, South China University of Technology, Guangzhou, China.

Abstract

Folate is commonly synthesized in natural plants and is an essential water-soluble vitamin of great importance inhuman health. Although the key genes involved in folate biosynthesis and transformation pathways have been identified in plants, the genetic architecture of folate in sweet corn kernels remain largely unclear. In this study, an association panel of 295 inbred lines of sweet corn was constructed. Six folate derivatives were quantified in sweet corn kernels at 20 days after pollination and a total of 95 loci were identified for eight folate traits using a genome-wide association study. A peak GWAS signal revealed that natural variation in ZmFCL, encoding a 5-formyltetrahydrofolate cyclo-ligase, accounted for 30.12% of phenotypic variation in 5-FTHF content. Further analysis revealed that two adjacent SNPs on the second exon resulting in an AA-to-GG in the gene and an Asn-to-Gly change in the protein could be the causative variant influencing 5-FTHF content. Meanwhile, 5-FTHF content was negatively correlated with ZmFCL expression levels in the population. These results extend our knowledge regarding the genetic basis of folate and provide molecular markers for the optimization of folate levels in sweet corn kernels.

Keywords: folates; formyltetrahydrofolate cyclo-ligase; genetic basis; genome-wide association study; sweet corn.