Metabolomics Analysis Reveals the Pathway and Metabolites Related to Allelic Differences in Eating Quality between the Wxb and Wxin Alleles in Rice (Oryza Sativa L.)
摘要
The Wx locus is the primary determinant of rice grain eating quality, with Wxb and Wxin as the predominant alleles exhibiting distinct quality traits. However, their molecular mechanisms underlying grain metabolome regulation remain poorly understood. In this paper, genotype differences in rice eating quality and proximate compositions between the Wxb and Wxin alleles were investigated using two rice single-segment substitution lines carrying different Wx alleles. Compared with the Wxin line, the Wxb line exhibited significantly higher taste value and crude lipid content, while displayed an obviously lower level of crude protein. Furthermore, a non-targeted metabolomics approach was employed to reveal the mechanisms at the metabolic level of just how the Wx allelic variation affects rice eating quality. The results showed significant changes in 84 metabolites between the two rice samples in terms of individual metabolite levels. These metabolites are involved in 47 metabolic pathways. Further pathway enrichment analysis indicated that relevant functions of the differentially accumulated metabolites on amino acid metabolism, unsaturated fatty acid metabolism and TCA cycle may play important roles in distinguishing the Wxb and Wxin alleles. This study elucidates the Wx allele-specific metabolic regulation, demonstrating how allelic variants modulate eating quality through differential metabolite accumulation in key metabolic pathways.