钙依赖蛋白激酶GmCDPK SK5参与田间高温高湿胁迫下春大豆种子活力形成的机制

Calcium-dependent protein kinase (CDPK), regulated by Ca2+ signal, is involved in plant growth and development and in response to various abiotic stresses. We have found previous that GmCDPK SK5 is related to the formation of seed vigor of spring soybean under high temperature and humidity stress. In the present project, firstly, the aims of us are to identify the key proteins that are interacted with GmCDPK SK5 and understand their interaction modes; secondly, we hope to understand the dynamic change of Ca2+ level in seed of the germplasms with high and low seed vigor before and after high temperature and humidity stress, together with its effects on the expression of GmCDPK SK5 and the interacting proteins; thirdly, we will study how GmCDPK SK5 and the interacting proteins are regulated by Ca2+ signal under high temperature and humidity stress through gene silencing and overexpressing; fourthly, we will analyze how GmCDPK SK5 participates in the formation of seed vigor; finally, based on all the above results, we will reveal the mechanism of calcium-dependent protein kinases GmCDPK SK5 participating in seed vigor formation of spring soybean under high temperature and humidity stress. All the results of this project will be helpful from one side for elucidating the formation mechanism of seed vigor of spring soybean under high temperature and humidity stress and enrich our understanding of the regulation approaches of Ca2+ signal in response to adversity (high temperature and humidity stress), which will provide regulation thoughts for the high quality production of seed and commercial soybean.

钙依赖蛋白激酶受钙离子信号调控，参与植物生长发育和对多种非生物逆境信号的响应。项目组前期研究中发现GmCDPK SK5与高温高湿胁迫下春大豆种子活力的形成相关，本项目拟以GmCDPK SK5为对象，在活力形成关键时期：①揭示高温高湿胁迫下与其互作的关键蛋白及其互作方式；②明确胁迫前后高低种子活力种质种子中Ca2+浓度动态变化及其对GmCDPK SK5以及互作蛋白表达的影响；③通过基因沉默和过表达转化拟南芥或大豆，研究高温高湿胁迫下GmCDPK SK5与互作蛋白受钙信号调控的方式；④进一步对GmCDPK SK5参与种子活力形成的功能进行分析；⑤从而揭示GmCDPK SK5参与田间高温高湿胁迫下春大豆种子活力形成的机制。其结果将从一个侧面为阐明田间高温高湿胁迫下春大豆种子活力形成的机制提供帮助；拓宽对钙信号响应逆境(田间高温高湿)胁迫的调控途径认识，为种用以及商用春大豆优质生产提供调控思路。

钙依赖蛋白激酶受钙离子信号调控，参与植物生长发育和对多种非生物逆境信号的响应。本项目拟以GmCDPK SK5为对象，在活力形成关键时期：（1）揭示高温高湿胁迫下与其互作的关键蛋白及其互作方式；（2）明确胁迫前后高低种子活力种质种子中Ca2+浓度动态变化及其对GmCDPK SK5以及互作蛋白表达的影响；（3）通过基因沉默和过表达转化拟南芥或大豆，研究高温高湿胁迫下GmCDPK SK5与互作蛋白受钙信号调控的方式；（4）进一步对GmCDPK SK5参与种子活力形成的功能进行分析；（5）从而揭示GmCDPK SK5参与田间高温高湿胁迫下春大豆种子活力形成的机制。结果表明：（1）通过酵母文库筛选出与GmCDPK SK5互作的5个关键蛋白GmFAD2-1B、GmLEA、GmPM27、GmUGT73F4和 GmTCTP并用酵母双杂验证其互作关系；（2）在高温、高湿和高温高湿胁迫下，不管是抗性品种号还是不抗品种，其叶片细胞里游离的Ca2+增加；在外源施加Ca2+的情况下，GmCDPK SK5基因呈下调表达趋势；（3）高温高湿胁迫和外施Ca2+条件下，GmCDPK SK5通过影响阳离子交换器（Cation Exchange, CAXs）和Ca2+-ATPases（ACA4, ACA8）基因的表达来影响钙离子在叶片细胞内的平衡，以及通过影响GmFAD2-1B的表达来影响细胞膜的过氧化程度，从而响应逆境的胁迫。其结果从一个侧面为阐明田间高温高湿胁迫下春大豆种子活力形成的机制提供帮助；拓宽对钙信号响应逆境(田间高温高湿)胁迫的调控途径认识，为种用以及商用春大豆优质生产提供调控思路。.发表相关论文10篇，授权发明专利1项。