Investigation of Mechanisms that Control the Transition to Flowering in Higher Plants

控制高等植物开花过渡的机制研究

• 批准号: RGPIN-2017-03930
• 负责人: Colasanti, Joseph
• 金额: $ 2.84万
• 依托单位: University of Guelph
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=761143
• 关键词: Investigation; Mechanisms; Control; Transition; Flowering

Plant biologists have been slowly deciphering how plants control flowering time for over a century. 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 from which the actual flowers originate. My research uses the tools of molecular biology, genetics, 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 functional version of this gene flower at the proper time, whereas maize plants with a defective ID1 gene flower very late and produce aberrant flowers. We used molecular techniques to isolate and characterize the ID1 gene and found that it encodes a zinc finger transcription factor protein that acts in leaves as a master regulator of other genes. This suggests that ID1 causes flowering in maize by turning 'on' or 'off' the genes that control the long distance leaf signal. There are three main goals of this proposal: 1) identify genes that are controlled by the ID1 gene, 2) characterize the molecular, biochemical and physiological components in plants that make up the leaf signals that specify time to flower; and 3) work out the basic molecular mechanism used by ID1 to make genes active or inactive. Recently we found evidence that one way that ID1 may control genes is by epigenetic mechanisms. Epigenetics represents an exciting new paradigm in our understanding of how genes are controlled. Ultimately we aim to decipher the epigenetic mechanisms that underpin ID1 function leading to the biochemical components and metabolic changes that affect the flowering process. Discovering how flowering time works is vitally important to agriculture. Global climate change, coupled with an expanding population, will have a severe impact on the world food supply. A better understanding of flowering in maize and agriculturally important relatives such as wheat, rice, sorghum and sugarcane could help stabilize food production. The ability to control time to flowering is of fundamental 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.

一个多世纪以来，植物生物学家一直在慢慢破译植物如何控制开花时间。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枝条，到达真正开花的干细胞区域。我的研究使用分子生物学、遗传学、生物化学和基因组学的工具来更好地了解开花过程的本质。我们的研究围绕玉米 INDETERMINATE1 基因（ID1）的研究，该基因对于开花至关重要。带有该基因功能版本的玉米植物会在适当的时间开花，而带有缺陷 ID1 基因的玉米植物则开花得很晚，并且会产生异常的花。我们使用分子技术来分离和表征 ID1 基因，发现它编码锌指转录因子蛋白，该蛋白在叶子中充当其他基因的主调节因子。这表明 ID1 通过“打开”或“关闭”控制长距离叶子信号的基因来引起玉米开花。该提案有三个主要目标：1）识别由 ID1 基因控制的基因，2）表征植物中构成指定开花时间的叶子信号的分子、生化和生理成分； 3) 找出ID1使基因激活或失活的基本分子机制。最近我们发现证据表明 ID1 控制基因的一种方式是通过表观遗传机制。表观遗传学代表了我们理解基因如何控制的一个令人兴奋的新范式。最终，我们的目标是破译支持 ID1 功能的表观遗传机制，从而导致影响开花过程的生化成分和代谢变化。了解开花时间如何运作对于农业至关重要。全球气候变化，加上人口不断增长，将对世界粮食供应产生严重影响。更好地了解玉米和小麦、水稻、高粱和甘蔗等重要农业亲缘植物的开花情况有助于稳定粮食生产。控制开花时间的能力对于农业至关重要，因为植物可以协调开花以获得最佳的种子和果实生产。因此，了解开花将有助于提高重要作物的生产力。