植物不能移动，靠改变生理生长状态来适应环境变化，并演化出适应不同环境丰富的多样性。十字花科是被子植物一个重要的科，包括青菜萝卜等作物和模式植物拟南芥，还有三千多种适应不同环境的野生植物。人们在拟南芥研究中发现了多个抗旱、抗盐相关基因，利用多个十字花科物种的基因组信息，为进一步研究植物抗逆基因功能的微进化提供了有利条件。申请人实验室的前期研究也初步确定十字花科内部大分支之间的关系，加强了利用十字花科近缘种进行环境适应性微进化研究的优势。针对植物适应极端环境的调控因子和通路的进化机制这一科学问题，本项目拟：（1）通过转录组分析，进一步确定十字花科的物种关系，并以此为基础认识基因表达和功能的演化规律；（2）选择少数关键基因在拟南芥、盐芥和蔬菜间进行功能比较研究；（3）针对十字花科和其他被子植物的抗逆基因及其同源基因，开展基因家族的分子进化分析，探索基因进化规律，并为功能变化提供借鉴。

Plants cannot move and must alter their physiological and growth status to acclimate to environmental changes, thereby having evolved rich diversity in adaptation to various environments. Brassicaceae is one of the most important angiosperm families, including Brassica vegetables and oil crops, the model plant Arabidopsis thaliana, and over 3000 wild species that have adapted to different environments. Research in Arabidopsis has uncovered many genes important for salt and drought tolerance, and at 10 Brassicaceae species have sequenced genomes, providing a strong foundation for studying the microevolution of genes that confer stress tolerance/resistance. The laboratory of the applicant has previously investigated the phylogenetic relations of Brassicaceae, with resolution of major lineages of Brassicaceae. These results further enhances the advantages of Brassicaceae and its salt-tolerant members as a model system to study microevolution of response to environmental changes. Aiming to understand the evolutionary mechanisms of regulatory elements and pathways for plant environmental responses, this project will (1) using transcriptome datasets to further determine the relationships among the members of Brassicaceae and to examine the patterns of gene expression in responses to environment changes; (2) select a few key genes to functionally compare to the their homologs in other Brasscaceae species, particularly Arabidopsis, crops and salt cresses, using mutants and transgenic plants; (3) conduct molecular evolutionary analysis of gene families that include genes functional in environmental responses.