Age, as a threshold of floral competence acquisition, prevents precocious flowering when there is insufficient biomass, and ensures flowering independent of environmental conditions; however, the underlying regulatory mechanisms are largely unknown. In this study, silencing the expression of a nuclear factor gene, CmNF-YB8, from the short day plant chrysanthemum (Chrysanthemum morifolium), results in precocious transition from juvenile to adult, as well as early flowering, regardless of day length conditions. The expression of SQUAMOSA PROMOTER BINDING-LIKE (SPL) family members, SPL3, SPL5, and SPL9, is upregulated in CmNF-YB8-RNAi plants, while expression of the microRNA, cmo-MIR156, is downregulated. In addition, CmNF-YB8 is shown to bind to the promoter of the cmo-MIR156 gene. Ectopic expression of cmo-miR156, using a virus-based microRNA expression system, restores the early flowering phenotype caused by CmNF-YB8 silencing. These results show that CmNF-YB8 influences flowering time through directly regulating the expression of cmo-MIR156 in the aging pathway.The mechanisms by which plant age regulates flowering remain incompletely understood. Here the authors show that age dependent regulation of SPL transcription factors by miR156 influence flowering via control of NF-YB8 expression in Chrysanthemum.

中文翻译：

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通过与衰老途径的整合来控制菊花的开花。

年龄是获得花卉能力的阈值，可防止生物量不足时过早开花，并确保开花不受环境条件的影响；但是，基本的监管机制尚不清楚。在这项研究中，沉默短日植株菊花（Chrysanthemum morifolium）中的核因子基因CmNF-YB8的表达，无论幼年条件如何，都会导致从幼稚到成年的早熟过渡，以及早开花。在CmNF-YB8-RNAi植物中SQUAMOSA促进绑定样（SPL）家族成员SPL3，SPL5和SPL9的表达上调，而在microRNA cmo-MIR156的表达下调。另外，CmNF-YB8被显示与cmo-MIR156基因的启动子结合。cmo-miR156的异位表达 使用基于病毒的microRNA表达系统，可以恢复CmNF-YB8沉默引起的早期开花表型。这些结果表明CmNF-YB8通过直接调节衰老途径中cmo-MIR156的表达来影响开花时间。在这里，作者证明了miR156对SPL转录因子的年龄依赖性调节，通过控制菊花中的NF-YB8表达来影响开花。