State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs, Key Laboratory of State Forestry and Grassland Administration on Biology of Ornamental Plants in East China, College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China.
Zhongshan Biological Breeding Laboratory, No. 50 Zhongling Street, Nanjing, Jiangsu, 210014, China.
Plant J. 2023 Dec;116(6):1652-1666. doi: 10.1111/tpj.16453. Epub 2023 Sep 11.
TEMPRANILLO1 (TEM1) is a transcription factor belonging to related to ABI3 and VP1 family, which is also known as ethylene response DNA-binding factor 1 and functions as a repressor of flowering in Arabidopsis. Here, a putative homolog of AtTEM1 was isolated and characterized from chrysanthemum, designated as CmTEM1. Exogenous application of ethephon leads to an upregulation in the expression of CmTEM1. Knockdown of CmTEM1 promotes floral initiation, while overexpression of CmTEM1 retards floral transition. Further phenotypic observations suggested that CmTEM1 involves in the ethylene-mediated inhibition of flowering. Transcriptomic analysis established that expression of the flowering integrator CmAFL1, a member of the APETALA1/FRUITFULL subfamily, was downregulated significantly in CmTEM1-overexpressing transgenic plants compared with wild-type plants but was verified to be upregulated in amiR-CmTEM1 lines by quantitative RT-PCR. In addition, CmTEM1 is capable of binding to the promoter of the CmAFL1 gene to inhibit its transcription. Moreover, the genetic evidence supported the notion that CmTEM1 partially inhibits floral transition by targeting CmAFL1. In conclusion, these findings demonstrate that CmTEM1 acts as a regulator of ethylene-mediated delayed flowering in chrysanthemum, partly through its interaction with CmAFL1.
TEMPRANILLO1（TEM1）是一种转录因子，属于 ABI3 和 VP1 家族的相关因子，也被称为乙烯响应 DNA 结合因子 1，在拟南芥中作为开花的阻遏物发挥作用。在这里，从菊花中分离并鉴定出一个假定的 AtTEM1 同源物，命名为 CmTEM1。乙烯利的外源应用导致 CmTEM1 的表达上调。CmTEM1 的敲低促进花的起始，而 CmTEM1 的过表达则延迟花的转变。进一步的表型观察表明，CmTEM1 参与乙烯介导的开花抑制。转录组分析建立了表达的花整合子 CmAFL1，一个 APETALA1/FRUITFULL 亚家族的成员，在 CmTEM1 过表达转基因植物中与野生型植物相比显著下调，但通过定量 RT-PCR 验证在 amiR-CmTEM1 系中上调。此外，CmTEM1 能够结合 CmAFL1 基因的启动子来抑制其转录。此外，遗传证据支持 CmTEM1 通过靶向 CmAFL1 部分抑制花转变的观点。总之，这些发现表明 CmTEM1 作为菊花中乙烯介导的延迟开花的调节剂发挥作用，部分通过与 CmAFL1 的相互作用。
