DREB转录因子是植物响应逆境胁迫的一个重要基因家族。羊草LcDREB2基因在逆境胁迫下存在3种不同的选择性剪接产物，而拟南芥中的同源基因则不存在选择性剪接现象。本研究将以羊草LcDREB2为研究对象，使用生物信息软件构建系统进化树，推测LcDREB2基因的起源和进化；通过比对LcDREB2与禾本科植物中同源基因的基因组序列，来分析影响LcDREB2选择性剪接的顺式作用元件，采取基因定点突变、水稻快速遗传转化、Realtime-PCR和Western Blotting等策略来验证调控选择性剪接的关键元件；此外，还将通过免疫亲和层析和EMSA等方法，对LcDREB2上的顺式元件及相关反式作用因子进行深入研究，以此来阐明LcDREB2选择性剪接的分子机制。本项目的实施将进一步揭开DREB基因介导的逆境应答机制，同时为使用DREB基因进行植物资源评价和分子育种提供新的理论依据。

The transcription factor of DREB is one of the important gene families in plant in the process of resistance to adverse environment. LcDREB2 gene in Leymus chinensis produces three kinds of alternative splicing products under adversity stress, but there is no alternative splicing phenomenon in the homologous gene of Arabidopsis. The research will study the gene of LcDREB2, use bioinformatics software to construct phylogenetic trees, infer the origins and evolution of LcDREB2; The research will analysis cis-acting elements affecting the alternative splicing of LcDREB2 by genomic sequence alignment of LcDREB2 and its homologous genes in Graminaceous, and identify the key elements regulating alternative splicing by site-directed mutagenesis, rice rapid genetic transformation, Realtime-PCR and Western Blotting. Besides, the research will study cis-acting elements in LcDREB2 and relative trans-acting factors by immunoaffinity chromatography and EMSA. Finally, the molecular mechanism of alternative splicing of LcDREB2 could be clarified. This research will reveal the stress response mechanism regulated by DREB genes, evaluate plant resource and provide new insights for plant molecular breeding via using DREB genes.