LncRNA（HAL6）调控拟南芥高温胁迫响应的分子机制研究

Heat stress influences plant adversely in development, yield and quality. Long non-coding RNAs (lncRNAs), a category of transcriptional regulator found recently, play a crucial role in development and stress responses. However, the mechanism by which lncRNAs are employed to respond to stresses is unclear. In our previous study, we identified 136 heat-induced lncRNAs in Arabidopsis of which HAL6 could be induced significantly. Analysis shows HAL6 is ubiquitously expressed in most tissues and located in nucleus. Overexpression of HAL6 enables plant to become more resistant to heat stress which indicates that HAL6 functions as a key regulator to heat stress. RIP (RNA Binding Protein Immunoprecipitation) demonstrates HSP101 acts downstream of HAL6. Therefore, to further investigate the effect of HAL6 in plant physiology, we will screen and confirm the target protein.using high-throughput sequencing which would shed light on the molecular mechanism adopted by HAL6.This project will significantly expand our view of lncRNA regulating heat stress and development.

高温胁迫严重影响植物的生长发育、产量和品质。长链非编码RNA是近年来发现的基因表达调控因子，在生物体生长发育和胁迫响应过程中具有非常重要的生物学功能。但人们对植物胁迫应答过程中lncRNA的作用机制却知之甚少。我们的研究发现拟南芥中存在136个高温响应的lncRNA，其中HAL6表达量受到高温胁迫明显诱导。初步分析表明其在各个组织中均有表达，并定位在细胞质中。表型实验发现超表达HAL6明显提高转基因植物的高温抗性，说明HAL6为植物应答高温胁迫关键因子。RNA pull down实验初步筛选出HAL6互作蛋白为HSP101等功能蛋白，推测为HAL6下游直接靶蛋白。因此本项目通过深入研究HAL6的表达调控与生物学功能，结合高通量测序筛选与转基因功能鉴定靶蛋白，明确其参与高温胁迫的作用机理，阐明其自身调控机制，为深入理解lncRNA的作用机理提供全新的理论依据。

长链非编码RNA是近年来备受关注的基因表达调控因子，其作用涉及动植物的生长发育及外界逆境响应等多种生物学过程，具有重要的生物学功能。但人们对于植物lncRNA在应答外界逆境信号的功能及调控的机制却知之甚少。我们通过链特异转录组测序发现并鉴定了拟南芥高温响应的lncRNA HAL6。高温胁迫条件下，HAL6的转录水平明显升高，过表达HAL6植株萌发和成苗的高温抗性明显增加，说明HAL6为植物应答高温胁迫关键因子。因此本项目通过深入研究高温胁迫下HAL6功能和作用机制、明确高温胁迫和lncRNA之间的内在联系；结合突变体、RNA-IP技术等筛选鉴定HAL6调节蛋白HSFA2，阐明高温胁迫下HAL6的分子调控机制，为深入理解miRNA的作用机理提供全新的理论依据和应用工具。