转录因子FHY3/FAR1在远红光诱导番茄耐低温性中的作用机制

设施蔬菜低温生育障碍经常发生，探究其发生机理及防控技术意义重大。申请者近年发现远红光（FR）可通过光受体phyA提高番茄的耐低温性，且有研究表明：转录因子FHY3/FAR1参与phyA的信号转导，并诱导拟南芥肌醇的积累，但FHY3/FAR1是否通过调节肌醇参与FR诱导番茄耐低温性过程及其调控机制尚不清楚。因此，本项目在明确番茄FHY3/FAR1受低温及FR调控的基础上，构建其基因敲除及过表达植株，探究其在FR诱导番茄耐低温中的作用；利用转录组测序和VIGS技术，挖掘和验证受FHY3/FAR1调控的肌醇合成基因及其功能；通过酵母单杂交技术，分析FHY3/FAR1的转录激活活性；利用EMSA、ChIP-qPCR等技术，探索FHY3/FAR1与筛选到的肌醇合成基因间的互作机制。本项目旨在揭示FHY3/FAR1在FR诱导番茄耐低温性中的作用及调控机制，为利用光质诱导喜温蔬菜的耐低温性提供理论依据。

Low temperature often limits the growth and development of vegetables, so it is of great significance to explore the regulation mechanisms and protecting technologies of vegetables during cold stress. Recently, we have found that far-red light (FR) could increase the chilling tolerance of tomato plants via its primary photoreceptor phytochrome A (phyA). Previous reports showed that the transposase-derived transcription factors FAR-RED ELONGATED HYPOCOTYL3 (FHY3) and its homolog FARRED-IMPAIRED RESPONSE1 (FAR1) act in phyA signaling, and promote inositol biosynthesis in Arabidopsis, but whether FHY3/FAR1 could regulate inositol during FR induced chilling tolerance of tomato and its regulation mechanism remain largely unclear. Based on the found that genes expression of FHY3 and FAR1 were induced by FR under cold stress, in this project, we will study the role of FHY3/FAR1 in FR light-induced chilling tolerance in tomato by silencing and overexpressing the FHY3/FAR1 gene. Meanwhile, we will identify the critical downstream target genes of FHY3/FAR1 involved in inositol biosynthesis and dissect their roles in light quality-mediated chilling tolerance via transcriptomic data analysis and virus-induced gene silencing (VIGS), respectively. To further study the function of FHY3/FAR1, its transcriptional activation activity will be identified by yeast one-hybrid assay. In addition, we will analyze the interactions of FHY3/FAR1 transcription factor and its downstream target genes through EMSA, ChIP-qPCR and dual-luciferase assays. The functions and molecular mechanisms of FHY3/FAR1 regulation of inositol in FR light-induced chilling tolerance of tomato will be established from this research project, which will found theoretical basis for improving the chilling tolerance of vegetables via regulation of light-quality signals.