植物生长素调控种子和器官大小的分子机理研究

植物生长素调控许多重要的生物学过程，但生长素是如何调控器官分生组织和器官原基大小，从而决定种子和器官大小的分子机理并不清楚。植物种子与器官大小是重要的产量性状,其机理研究也是正在兴起的新研究领域。在前期植物激素重大研究计划的支持下，我们发现了植物种子和器官大小关键调节因子DA1与BTB结构域的蛋白EIP1直接互作，协同调控了生长素运输以及植物种子和器官大小。此发现为解析生长素参与调控植物种子和器官大小的分子机理提供了重要切入点。本研究拟以eip1-1，da1-1和eip1-1 da1-1突变体为材料，利用遗传学、细胞生物学和生物化学等为手段，解析DA1和EIP1协同调控生长素运输、分布以及决定种子和器官大小的遗传、细胞和生化基础，初步阐明植物生长素调控种子和器官大小的分子机理。本研究将揭示全新的植物生长素调控种子与器官大小的分子机制，也将为高产育种提供新的理论基础和基因资源。

Although auxin controls diverse biological processes, how auxin determines the final size of seeds and determinate organs by regulating meristem and primordium size is almost totally unknown. The final size of seeds and organs is an important agronomic trait，but the molecular mechanisms that set final seed and organ size are largely unknown. We have recently found that the seed and organ size regulator DA1 physically interacts with EIP1, a BTB domain containing protein, and DA1 acts synergistically with EIP1 to regulate auxin transport as well as seed and organ size. Thus, these findings provide a promising starting point for understanding the molecular mechanisms of seed and organ size control by auxin. In this project, a combination of genetic, cytological and biochemical approaches will be used to characterize the functions of DA1 and EIP1 in seed and organ size control, auxin transport as well as auxin distribution during organ growth. Our aims are to understand the genetic and molecular mechanisms of seed and organ size control by auxin. The expected results will greatly enhance our understanding of the molecular mechanisms regulating seed and organ size by auxin, and provide useful guidance and novel genes for crop breeding.