SKIP调控植物顶端分生组织形成和整合生长和逆境适应机制研究

高等植物能持续生长发育主要原因是顶端存在分生组织,其中茎顶端分生组织(SAM)含有分生能力的多能干细胞，干细胞通过细胞分裂和分化最终形成所有地上器官从而决定生长和发育。STM是调控SAM形成和维持的关键转录因子。另外,植物在长期进化过程形成了适应环境变化并保证物种生存的机制。由于植物生长时刻受到环境影响，个体生活史就是合适环境下的生长和逆境条件下的适应这两个相互拮抗过程的协调和整合,其中的机制一直是植物生物学关键核心问题,研究结果即有重大理论意义也有重要应用前景。该申请在我们前期结果证实SKIP做为剪接因子整合进入剪接复合体提高植物逆境性，与STM直接互作形成SKIP-STM转录激活复合体调控植物生长发育为基础,以SKIP即参与个体生长发育(通过SKIP-STM复合体)又参与胁迫耐受反应(通过剪接复合体)为切入点,研究SKIP是否参与以及如何参与协调和整合生长发育和环境适应的分子机制。

The apical meristems in shoot and root determines the continuous nature of development in higher plants. Shoot apical meristem (SAM) maintains the pluripotent cells, which will generate the entire above-ground body of higher plants. A homeodomain transcription factor SHOOT MERISTEMLESS (STM) is required for the establishment and maintainance of a SAM, therefore is the key player in the controlling of preventing the pluripotent cells in the SAM from adopting the differentiated cell fates, and in the continuous development of plant. In the other hand, as sessile organisms, plants must respond properly to environmental changes for their survival. Maintaining the proper balance between growth and environmental stress responses is key for plant survival, both in terms of individual plants and adapting to environmental changes during plant evolution. Plants promote growth under optimal conditions, shut down growth and respond to stress under unfavorable conditions, and stimulate re-growth after returning to unstressed conditions. Thus, growth and stress responses are generally antagonistic processes, and plants must balance the two during their life cycle. Much is known about the regulatory mechanisms involved in plant growth and stress responses, respectively, but little is known about the mechanisms that coordinate these processes. Recently, we confirmed that SKIP is a component of spliceosome complex to mediate abiotic stress responses by controlling the alternative splicing of pre-mRNAs encoded by stress tolerance-related genes. The proposed work will first confirm that SKIP interacts with STM to establish and maintain a SAM at transcriptional level, then reveals the mechanism that controls the integration between SKIP-STM complex-mediated growth and SKIP-spliceosome complex-mediated environmental fitness in Arabidopsis. Therefore, the results from the proposed work will provide new insight into our understanding the mechanism that establishes and maintains the SAM, and the mechanism that controls the integration of environmental fitness and development in plants.