• The floral transition of the maize (Zea mays ssp. mays) shoot apical meristem determines leaf number and flowering time, which are key traits influencing local adaptation and yield potential. dlf1 (delayed flowering1) encodes a basic leucine zipper protein that interacts with the florigen ZCN8 to mediate floral induction in the shoot apex. However, the mechanism of how dlf1 promotes floral transition remains largely unknown.
• We demonstrate that dlf1 underlies qLB7‐1, a quantitative trait locus controlling leaf number and flowering time that was identified in a BC₂S₃ population derived from a cross between maize and its wild ancestor, teosinte (Zea mays ssp. parviglumis). Transcriptome sequencing and chromatin immunoprecipitation sequencing demonstrated that DLF1 binds the core promoter of two AP1/FUL subfamily MADS‐box genes, ZmMADS4 and ZmMADS67, to activate their expression.
• Knocking out ZmMADS4 and ZmMADS67 both increased leaf number and delayed flowering, indicating that they promote the floral transition. Nucleotide diversity analysis revealed that dlf1 and ZmMADS67 were targeted by selection, suggesting that they may have played important roles in maize flowering time adaptation.
• We show that dlf1 promotes maize floral transition by directly activating ZmMADS4 and ZmMADS67 in the shoot apex, providing novel insights into the mechanism of maize floral transition.

中文翻译：

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dlf1通过直接激活玉米茎尖中的ZmMADS4和ZmMADS67来促进花期过渡。

• 玉米的花转变（玉蜀黍SSP。玉蜀黍）芽顶端分生组织决定叶片数和开花时间，这是影响局部适应和产量潜力的关键特征。dlf1（延迟开花）编码一种基本的亮氨酸拉链蛋白，该蛋白与荧光素ZCN8相互作用，以介导芽尖的花诱导。但是，dlf1如何促进花期转变的机制仍然未知。
• 我们表明，dlf1 underlies qLB7-1，数量性状基因座控制叶片数和开花这是在BC识别的时间₂ š ₃从玉米及其野生祖先，大刍草之间的杂交衍生的群体（玉蜀黍SSP。parviglumis）。转录组测序和染色质免疫沉淀测序表明，DLF1与两个AP1 / FUL亚家族MADS-box基因ZmMADS4和ZmMADS67的核心启动子结合，以激活它们的表达。
• 敲除ZmMADS4和ZmMADS67均增加叶数并延迟开花，表明它们促进了花期过渡。核苷酸多样性分析表明，dlf1和ZmMADS67通过选择成为靶标，表明它们可能在玉米开花时间适应中发挥了重要作用。
• 我们显示dlf1通过直接激活芽顶中的ZmMADS4和ZmMADS67来促进玉米花期过渡，从而为玉米花期过渡机制提供了新颖见解。