Deciphering Maize Floral Regulatory Networks

近世纪来，植物生物学家一直试图破译控制植物开花时间的机制。直到最近，导致植物开花的信号的本质仍然是一个完全的谜。早期研究人员发现，一种开花诱导物质在叶子中合成，然后长距离运输到植物的中央芽，到达真正开花的干细胞区域。我的研究使用分子生物学，生物化学和基因组学的工具，以更好地了解开花过程的性质。我们的研究围绕着玉米INDUSTRIATE 1基因或ID 1的研究，这对开花至关重要。具有该基因的正常拷贝的玉米植物在通常的时间开花，而具有突变的ID 1基因的玉米开花非常晚并且产生有缺陷的花。我们分离了ID 1基因，并利用分子技术对其进行了表征。ID 1编码锌指转录因子蛋白，其在叶片中作为其他基因的主调节因子，这表明ID 1通过打开或关闭其他基因并控制长距离叶片信号来引起玉米开花。该建议有三个主要目标：1）表征植物中构成指定开花时间的叶信号的分子、生物化学和生理组分; 2）鉴定由ID 1基因控制的基因;以及3）以研究ID 1活性为代表，制定出高等生物用于调节基因功能的基本分子机制。最终，我们希望确定影响开花过程的生化成分和代谢变化。此外，我们将更好地了解植物如何解释环境信号，以便它们在正确的时间开花。发现ID 1如何控制开花时间可以更好地了解玉米及其农业上重要的亲戚，如小麦，水稻，高粱，甘蔗和各种“能源草”，如芒草。控制开花时间的能力对农业至关重要，因为植物协调开花以获得最佳种子和果实产量。因此，了解开花将有助于提高重要作物的生产力。

For nearly a century plant biologists have been trying to decipher the mechanisms that control flowering time in plants. Until recently the nature of the signals that cause plants to flower remained a complete mystery. Early researchers discovered that a flower-inducing substance is synthesized in leaves and then transported a long distance to the central shoot of the plant to a region of stem cells where the actual flowers are made. My research uses the tools of molecular biology, biochemistry and genomics to better understand the nature of the flowering process. Our research revolves around the study of the maize INDETERMINATE1 gene, or ID1, which is critically important for flowering. Maize plants with a normal copy of this gene flower at the usual time, whereas maize with a mutated ID1 gene flowers very late and produces defective flowers. We isolated the ID1 gene and characterized it using molecular techniques. ID1 encodes a zinc finger transcription factor protein that acts in leaves as a master regulator of other genes, suggesting that ID1 causes flowering in maize by turning other genes 'on' or 'off' and controlling a the long distance leaf signal. There are three main goals of this proposal: 1) to characterize the molecular, biochemical and physiological components in plants that make up the leaf signals that specify time to flower; 2) to identify genes that are controlled by the ID1 gene, and 3) to work out the basic molecular mechanisms, as typified by studying ID1 activity, used by higher organisms to regulate gene function. Ultimately we would like to identify the biochemical components and metabolic changes that affect the flowering process. Moreover, we will better understand how plants interpret environmental signals so that they flower at the correct time. Discovering how ID1 controls flowering time could lead to a better understanding of flowering in maize as well its agriculturally important relatives such as wheat rice, sorghum, sugarcane and various 'energy grasses' such as Miscanthus. The ability to control time to flowering is of vital importance to agriculture because plants coordinate flowering for optimal seed and fruit production. Therefore understanding flowering will help to improve the productivity of vital crop plants.