Key Laboratory of Genetics and Fruit Development, College of Horticultural, Nanjing Agricultural University, Nanjing, China.
China Wine Industry Technology Institute, Yinchuan, China.
BMC Plant Biol. 2020 Dec 4;20(1):544. doi: 10.1186/s12870-020-02754-0.
Grape buds and leaves are directly associated with the physiology and metabolic activities of the plant, which is monitored by epigenetic modifications induced by environment and endogenous factors. Methylation is one of the epigenetic regulators that could be involved in DNA levels and affect gene expression in response to stimuli. Therefore, changes of gene expression profile in leaves and bud through inhibitors of DNA methylation provide a deep understanding of epigenetic effects in regulatory networks.
In this study, we carried out a transcriptome analysis of 'Kyoho' buds and leaves under 5-azacytidine (5-azaC) exposure and screened a large number of differentially expressed genes (DEGs). GO and KEGG annotations showed that they are mainly involved in photosynthesis, flavonoid synthesis, glutathione metabolism, and other metabolic processes. Functional enrichment analysis also provided a holistic perspective on the transcriptome profile when 5-azaC bound to methyltransferase and induced demethylation. Enrichment analysis of transcription factors (TFs) also showed that the MYB, C2H2, and bHLH families are involved in the regulation of responsive genes under epigenetic changes. Furthermore, hormone-related genes have also undergone significant changes, especially gibberellin (GA) and abscisic acid (ABA)-related genes that responded to bud germination. We also used protein-protein interaction network to determine hub proteins in response to demethylation.
These findings provide new insights into the establishment of molecular regulatory networks according to how methylation as an epigenetic modification alters transcriptome patterns in bud and leaves of grape.
葡萄芽和叶片与植物的生理和代谢活动直接相关，这些活动受环境和内源性因素诱导的表观遗传修饰所监测。甲基化是一种表观遗传调控因子，它可能参与 DNA 水平的调节，并响应刺激影响基因表达。因此，通过 DNA 甲基化抑制剂在叶片和芽中观察到的基因表达谱变化，为深入了解调控网络中的表观遗传效应提供了依据。
在这项研究中，我们对‘巨峰’芽和叶片在 5-氮杂胞苷（5-azaC）暴露下的转录组进行了分析，并筛选了大量差异表达基因（DEGs）。GO 和 KEGG 注释表明，它们主要参与光合作用、类黄酮合成、谷胱甘肽代谢等代谢过程。功能富集分析也为 5-azaC 与甲基转移酶结合并诱导去甲基化时的转录组谱提供了整体视角。转录因子（TFs）的富集分析也表明，MYB、C2H2 和 bHLH 家族参与了响应基因在表观遗传变化下的调控。此外，激素相关基因也发生了显著变化，特别是赤霉素（GA）和脱落酸（ABA）相关基因对芽萌发的响应。我们还使用蛋白质-蛋白质相互作用网络来确定响应去甲基化的枢纽蛋白。
这些发现为根据甲基化作为一种表观遗传修饰如何改变葡萄芽和叶片的转录组模式，建立分子调控网络提供了新的见解。
