Institute of Chinese Medicinal Materials, Nanjing Agricultural University, Nanjing 210095, China.
Int J Mol Sci. 2024 Sep 18;25(18):10037. doi: 10.3390/ijms251810037.
L. capitulum is an enriched source of flavonoids with broad-ranging biological activities, mainly due to their anti-inflammatory, anti-cancer, immune regulation, anti-microbial activity, hepatoprotective, and neuroprotective effects. The -methylation of various secondary metabolites has previously been demonstrated to be mainly catalyzed by -adenosyl-L-methionine-dependent -methyltransferase (OMT) proteins encoded by the gene family. However, limited comprehensive study was published on the gene family, especially the subfamily, involved in the -methylation of flavonoids in Chrysanthemum. Here, we analyzed the spatiotemporal expression patterns of . genes in leaf and flower at different developmental stages. Transcriptome sequencing and qRT-PCR analysis showed that s were mainly highly expressed in capitulum, especially in full bloom, while s were mainly highly expressed in leaves. Correlation analysis of gene expression and flavonoids accumulation revealed that four s (, , , and ) were putatively involved in most methylated flavonoids biosynthesis in the capitulum. Furthermore, we identified a true CCoAOMT enzyme, CiCCoAOMT1, and found that it catalyzed -methylation of quercetin and luteolin at the 3'-OH position. In summary, this work provides an important theoretical basis for further research on the biological functions of s in . .
头状花序是黄酮类化合物的丰富来源，具有广泛的生物活性，主要归因于其抗炎、抗癌、免疫调节、抗微生物活性、保肝和神经保护作用。先前已经证明，各种次生代谢物的 -甲基化主要由基因家族编码的 -腺苷-L-甲硫氨酸依赖性 -甲基转移酶（OMT）蛋白催化。然而，关于基因家族，特别是黄酮类化合物 -甲基化涉及的 亚家族，在菊花中尚未进行全面的综合研究。在这里，我们分析了不同发育阶段叶和花中. 基因的时空表达模式。转录组测序和 qRT-PCR 分析表明，s 主要在头状花序中高度表达，特别是在盛开期，而 s 主要在叶片中高度表达。基因表达与黄酮类化合物积累的相关性分析表明，四个 s（,, 和 ）可能参与了头状花序中大多数甲基化黄酮类化合物的生物合成。此外，我们鉴定了一个真正的 CCoAOMT 酶 CiCCoAOMT1，并发现它催化槲皮素和木樨草素在 3'-OH 位置的 -甲基化。总之，这项工作为进一步研究 s 在 中的生物学功能提供了重要的理论依据。
