Li Zengqiang, Tang Meiqiong, Luo Dengjie, Kashif Muhammad Haneef, Cao Shan, Zhang Wenxian, Hu Yali, Huang Zhen, Yue Jiao, Li Ru, Chen Peng
Key Laboratory of Plant Genetics and Breeding, College of Agriculture, Guangxi University, Nanning, China.
College of Life Science and Technology, Guangxi University, Nanning, China.
Front Plant Sci. 2021 Aug 26;12:709030. doi: 10.3389/fpls.2021.709030. eCollection 2021.
DNA methylation regulates key biological processes in plants. In this study, kenaf seedlings were pretreated with the DNA methylation inhibitor 5-azacytidine (5-azaC) (at concentrations of 0, 100, 200, 400, and 600 μM), and the results showed that pretreatment with 200 μM 5-azaC promoted flowering most effectively. To elucidate the underlying mechanism, phytohormone, adenosine triphosphate (ATP), and starch contents were determined, and genome-wide DNA methylation and transcriptome analyses were performed on anthers pretreated with 200 μM 5-azaC (5-azaC200) or with no 5-azaC (control conditions; 5-azaC0). Biochemical analysis revealed that 5-azaC pretreatment significantly reduced indoleacetic acid (IAA) and gibberellic acid (GA) contents and significantly increased abscisic acid (ABA) and ATP contents. The starch contents significantly increased in response to 200 and 600 μM 5-azaC. Further genome-wide DNA methylation analysis revealed 451 differentially methylated genes (DMGs) with 209 up- and 242 downregulated genes. Transcriptome analysis showed 3,986 differentially expressed genes (DEGs), with 2,171 up- and 1,815 downregulated genes. Integrated genome-wide DNA methylation and transcriptome analyses revealed 72 genes that were both differentially methylated and differentially expressed. These genes, which included s, , , , , , and , are involved mainly in plant hormone signal transduction, starch and sucrose metabolism, and flowering regulation and may be involved in early flowering. This study serves as a reference and theoretical basis for kenaf production and provides insights into the effects of DNA methylation on plant growth and development.
DNA甲基化调控植物中的关键生物学过程。在本研究中，用DNA甲基化抑制剂5-氮杂胞苷（5-azaC）（浓度为0、100、200、400和600 μM）预处理红麻幼苗，结果表明，用200 μM 5-azaC预处理最有效地促进了开花。为阐明其潜在机制，测定了植物激素、三磷酸腺苷（ATP）和淀粉含量，并对用200 μM 5-azaC（5-azaC200）预处理或未用5-azaC预处理（对照条件；5-azaC0）的花药进行了全基因组DNA甲基化和转录组分析。生化分析表明，5-azaC预处理显著降低了吲哚乙酸（IAA）和赤霉素（GA）含量，并显著增加了脱落酸（ABA）和ATP含量。响应200和600 μM 5-azaC，淀粉含量显著增加。进一步的全基因组DNA甲基化分析揭示了451个差异甲基化基因（DMG），其中209个基因上调，242个基因下调。转录组分析显示有3986个差异表达基因（DEG），其中2171个基因上调，1815个基因下调。全基因组DNA甲基化和转录组综合分析揭示了72个基因既存在差异甲基化又存在差异表达。这些基因包括s、 、 、 、 、 和 ，主要参与植物激素信号转导、淀粉和蔗糖代谢以及开花调控，可能与早期开花有关。本研究为红麻生产提供了参考和理论依据，并为DNA甲基化对植物生长发育的影响提供了见解。
