CBF信号通路在植物适应低温胁迫时发挥重要的调控功能。ICE1是CBF信号途径上游关键的转录因子之一，鉴定ICE1的互作蛋白并阐明它们之间的调控关系，对于深入理解CBF通路具有一定的理论意义。在前期研究中我们发现PIF6转录因子与ICE1相互作用形成蛋白复合物。表型分析表明，PIF6可能负调控植物的耐冻性。然而，PIF6 与ICE1相互作用调控植物耐冻性的分子机理尚不清楚。在原有研究基础上，本项目将采用分子生物学、遗传学及生物化学的方法手段，进一步确定PIF6调控植物耐冻性的生物学功能，分析PIF6是否直接结合CBF基因的启动子调控其表达，揭示PIF6与ICE1、CBF之间的遗传关系，并详细阐明它们之间可能存在的调控效应。本项目的研究结果不仅有助于人们全面解析ICE–CBF 信号通路及植物耐冻性的分子机理，还有助于人们综合认识PIF家族成员调控植物某些重要生理过程的功能与机制。

CBF signaling pathway plays a central role in regulating plant cold acclimation. Previous studies demonstrated that ICE1 transcription factor functions as a crucial regulator of the CBF pathway to positively modulate plant freezing tolerance. Identifying potential interacting partners of ICE1 and further illustrating the regulatory effects between ICE1 and its interacting proteins will shed new light on the mechanisms of ICE1-CBF signaling pathway and freezing tolerance of plants. Recently, we found that PIF6 transcription factor physically interacts with ICE1 in vitro and in vivo. Phenotypic analysis showed that disruption of PIF6 renders plants more tolerant to freezing temperatures, suggesting that PIF6 may negatively mediate plant freezing tolerance. To explore the molecular mechanism of PIF6-modulated freezing stress response, we will undertake the methods of molecular biology, genetics and biochemistry to further analyze the biological function of PIF6 and reveal the genetic relationships between PIF6 and ICE1 or CBF. Moreover, we are also planning to investigate whether PIF6 affects the transcriptional function, DNA-binding activity, and/or stability of ICE1. The results of this project not only contribute to explore the molecular mechanisms of ICE-CBF pathway-mediated plant freezing tolerance, but also help us comprehensively understand the biological functions of PIF proteins in regulating various physiological processes.