Epigenetic regulation of the autonomous pathway mediates the flowering of Arabidopsis thaliana

Studies have shown that plant flowering time is affected by endogenous and exogenous factors, but the role of DNA methylation in flowering still remains unclear. Here, 27 Arabidopsis thaliana populations were used to determine how autonomous pathway gene methylation affects flowering differences by regulating gene expression patterns. DNA methylation analysis, qPCR and transgenic verification were performed. The flowering time of the Arabidopsis populations ranged from 19 to 55 days. Methylation of the coding regions of six upstream genes in the autonomous pathway, FVE, FY, FLD, PEP, HDA5 and PPR 39-1, was significantly correlated with flowering time and relative expression levels (P &lt; 0.05). Expression of FVE and FVE(CS) separately through codon degeneracy substitution (resulting in a reduction in cytosine) led to early flowering (by 8 days and 25 days, respectively). The flowering times of the FVE and FVE(CS) transgenic plants and the Col-0 plants were associated with the number of...已有研究证实，植物开花时间受内源与外源因素共同调控，但DNA甲基化在植物开花过程中所发挥的具体作用仍未明确。本研究以27个拟南芥（Arabidopsis thaliana）种群为材料，通过调控基因表达模式，解析自主开花途径（autonomous pathway）基因甲基化对开花时间差异的影响机制。实验开展了DNA甲基化分析、qPCR检测及转基因验证。供试拟南芥种群的开花时间跨度为19至55天。自主开花途径中6个上游基因（FVE、FY、FLD、PEP、HDA5及PPR 39-1）的编码区甲基化水平与开花时间及相对表达量均呈显著相关（P < 0.05）。通过密码子简并替换（可使胞嘧啶含量降低）分别过表达FVE与FVE(CS)，可使植株提早开花，分别提前8天与25天。FVE、FVE(CS)转基因植株及Col-0野生型植株的开花时间与……数量相关。