Light and temperature are two core environmental factors that coordinately regulate plant growth and survival throughout their entire life cycle. However, the mechanisms integrating light and temperature signaling pathways in plants remain poorly understood. Here, we report that CBF 1, an AP 2/ERF ‐family transcription factor essential for plant cold acclimation, promotes hypocotyl growth under ambient temperatures in Arabidopsis . We show that CBF 1 increases the protein abundance of PIF 4 and PIF 5, two phytochrome‐interacting bHLH ‐family transcription factors that play pivotal roles in modulating plant growth and development, by directly binding to their promoters to induce their gene expression, and by inhibiting their interaction with phyB in the light. Moreover, our data demonstrate that CBF 1 promotes PIF 4/PIF 5 protein accumulation and hypocotyl growth at both 22°C and 17°C, but not at 4°C, with a more prominent role at 17°C than at 22°C. Together, our study reveals that CBF 1 integrates light and temperature control of hypocotyl growth by promoting PIF 4 and PIF 5 protein abundance in the light, thus providing insights into the integration mechanisms of light and temperature signaling pathways in plants.

中文翻译：

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冷响应调节剂CBF1在环境温度下促进拟南芥下胚轴生长。

光照和温度是两个在整个生命周期中协调调节植物生长和存活的核心环境因素。然而，对植物中整合光和温度信号传导途径的机制仍知之甚少。在这里，我们报告说，CBF 1，一种AP 2 / ERF家族转录因子，对于植物的冷驯化至关重要，它在拟南芥属环境温度下促进胚轴生长。。我们显示CBF 1增加了PIF 4和PIF 5的蛋白质​​丰度，这两个与植物色素相互作用的bHLH家族转录因子在调节植物生长和发育中起着关键作用，通过直接结合它们的启动子来诱导其基因表达，并通过在光照下抑制它们与phyB的相互作用。此外，我们的数据表明CBF 1在22°C和17°C（而不是4°C）下都促进PIF 4 / PIF 5蛋白积累和下胚轴生长，在17°C时比在22°C时更显着。在一起，我们的研究表明，CBF 1通过促进光中的PIF 4和PIF 5蛋白丰度，整合了光和下胚轴生长的温度控制，从而为植物中光和温度信号通路的整合机制提供了见识。