帽结合蛋白CBP20/CBP80调控植物响应冷胁迫的机理研究

低温胁迫是决定植物生长发育和地理分布的主要限制因子，研究植物响应冷胁迫的分子机制，将为改良和培育抗冷抗冻农作物品种提供重要的理论依据。在真核生物中，细胞核内的帽结合蛋白复合体(cap-binding complex，CBC)在RNA的转录和转录后调控上起着重要作用；CBC由CBP20 和CBP80两个亚基组成。植物CBC参与植物的生长发育与抗逆反应；我们首次发现拟南芥CBP20和CBP80缺失突变体对冷胁迫十分敏感，暗示CBC蛋白参与拟南芥对低温胁迫的响应过程。本项目将利用拟南芥和水稻为材料，进一步研究在低温胁迫下，CBC作为重要的RNA调控因子，如何通过对相关基因的RNA转录和转录后调控机制以及新的分子功能来响应植物抗冷的分子机理。本项目的研究将促进我们进一步了解植物响应冷胁迫的新机制，也为我们在农业生产中CBC蛋白对植物抗冷的调控提供新的理论依据。

Cold stress is one of the major abiotic stresses that limits plant growth, productivity, and geographical distribution. Understanding of the molecular mechanisms in plant cold stress response will provide us with the theoretical basis for engineering or breeding of chilling- and freezing- tolerant crop plants in agriculture. In eukaryotes, the nuclear cap-binding complex (CBC) has a key role in transcriptional and post-transcriptional regulations of RNAs. CBC consists of two subunits of CBP20 and CBP80. In plant, CBC was demonstrated to be involved in plant growing development and stress responses. Here we found that the Arabidopsis cbp20, cbp80 and cbp20/80 mutants, all of which showed the increased sensitivity to cold stress, indicating that CBC is required for Arabidopsis tolerance to cold stress. In this project we will use Arabidopsis (Arabidopsis thaliana) and rice (Oryza sativa) as the materials to further investigate how CBC, as an important RNA regulator, regulate genes’ transcription, post-transcription or through new functions to modulate plant response to cold stress. Such project will help us further understand the underlying new mechanism in plant cold stress response, and also provide us with the theoretical basis for CBC enhancing the plants tolerance to cold stress in agriculture.