Uchida Kai, Kim June-Sik, Sato Muneo, Tabeta Hiromitsu, Mochida Keiichi, Hirai Masami Yokota
RIKEN Center for Sustainable Resource Science, Yokohama, Kanagawa, Japan.
Institute of Plant Science and Resources, Okayama University, Kurashiki, Okayama, Japan.
Front Plant Sci. 2023 Jun 8;14:1201129. doi: 10.3389/fpls.2023.1201129. eCollection 2023.
A genome-wide association study (GWAS), which uses information on single nucleotide polymorphisms (SNPs) from many accessions, has become a powerful approach to gene identification. A metabolome GWAS (mGWAS), which relies on phenotypic information based on metabolite accumulation, can identify genes that contribute to primary and secondary metabolite contents. In this study, we carried out a mGWAS using seed metabolomic data from accessions obtained by liquid chromatography-mass spectrometry to identify SNPs highly associated with the contents of metabolites such as glucosinolates. These SNPs were present in genes known to be involved in glucosinolate biosynthesis, thus confirming the effectiveness of our analysis. We subsequently focused on SNPs detected in an unknown methyltransferase gene associated with -methylhistidine content. Knockout and overexpression of lines of this gene had significantly decreased and increased -methylhistidine contents, respectively. We confirmed that the overexpressing line exclusively accumulated histidine methylated at the pi position, not at the tau position. Our findings suggest that the identified methyltransferase gene encodes a key enzyme for -methylhistidine biosynthesis in .
全基因组关联研究（GWAS）利用来自多个种质的单核苷酸多态性（SNP）信息，已成为一种强大的基因鉴定方法。代谢组全基因组关联研究（mGWAS）依赖基于代谢物积累的表型信息，能够鉴定影响初级和次级代谢物含量的基因。在本研究中，我们利用液相色谱-质谱法获得的种质种子代谢组数据开展了一项mGWAS，以鉴定与芥子油苷等代谢物含量高度相关的SNP。这些SNP存在于已知参与芥子油苷生物合成的基因中，从而证实了我们分析的有效性。随后，我们聚焦于在一个与β-甲基组氨酸含量相关的未知甲基转移酶基因中检测到的SNP。该基因敲除和过表达株系的β-甲基组氨酸含量分别显著降低和增加。我们证实，过表达株系仅积累了在π位而非τ位甲基化的组氨酸。我们的研究结果表明，鉴定出的甲基转移酶基因编码了β-甲基组氨酸在[具体物种]中生物合成的关键酶。
