Genome-wide association studies of free amino acid levels by six multi-locus models in bread wheat

Genome-wide association studies (GWAS) have been widely used to dissect the complex biosynthetic processes of plant metabolome. Most studies have used singlelocus GWAS approaches, such as mixed linear model (MLM), and little is known about more efficient algorithms to implement multi-locus GWAS. Here, we report a comprehensive GWAS of 20 free amino acid (FAA) levels in kernels of bread wheat (Triticum aestivum L.) based on 14,646 SNPs by six multi-locus models (FASTmrEMMA, FASTmrMLM, ISISEM-BLASSO, mrMLM, pKWmEB, and pLARmEB). Our results showed that 328 significant quantitative trait nucleotides (QTNs) were identified in total (38, 8, 92, 45, 117, and 28, respectively, for the above six models). Among them, 66 were repeatedly detected by more than two models, and 155 QTNs appeared only in one model, indicating the reliability and complementarity of these models. We also found that the number of significant QTNs for different FAAs varied from 8 to 41, which revealed the complexity of the genetic regulation of metabolism, and further demonstrated the necessity of the multi-locus GWAS. Around these significant QTNs, 15 candidate genes were found to be involved in FAA biosynthesis, and one candidate gene (TraesCS1D01G052500, annotated as tryptophan decarboxylase) was functionally identified to influence the content of tryptamine in vitro. Our study demonstrated the power and efficiency of multi-locus GWAS models in crop metabolome research and provided new insights into understanding FAA biosynthesis in wheat.

Saved in:
Bibliographic Details
Main Authors: Yanchun Peng, Hongbo Liu, Chen, J., Taotao Shi, Chi Zhang, Dongfa Sun, He Zhonghu, Yuanfeng Hao, Wei Chen
Format: Article biblioteca
Language:English
Published: Frontiers 2018
Subjects:AGRICULTURAL SCIENCES AND BIOTECHNOLOGY, Genome-Wide Association Study, Multi-Locus Models, QTNs, SOFT WHEAT, FREE AMINO ACIDS, GENOMIC FEATURES,
Online Access:https://hdl.handle.net/10883/19893
Tags: Add Tag
No Tags, Be the first to tag this record!