Molecular genetic investigation of land plant gravity signaling

陆地植物重力信号的分子遗传学研究

• 批准号: 2124689
• 负责人: Edgar Spalding
• 金额: $ 90.73万
• 依托单位: University of Wisconsin-Madison
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-06-15 至 2025-05-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2124689&HistoricalAwards=false
• 关键词: Molecular; genetic; investigation; land; plant

As plants colonized land some 400 million years ago, they evolved the ability to orient the growth of their roots and shoots using the Earth’s gravity vector as a guide. The underlying gravity sensing and response system is not well understood, even though modification of it through selective breeding has importantly shaped today’s crop plants and trees, and future gains in productivity are expected to attend modifications that result in steeper roots better able to reach water sources, and shoots with angles that intercept light better when plants are crowded in high-density production scenarios. This project aims to identify the proteins, which are encoded by genes, that make up the gravity sensing mechanism in the Arabidopsis thaliana plant, which is a model for plants in general. The project builds off of research indicating that a small number of LAZY genes, found only in land plants, encode key components of the gravity signaling system that orients roots and shoots. The project will use experimental methods from the fields of genetics and biochemistry to find genes and their proteins that function with LAZY proteins to create a pathway within cells that translates the gravity vector into a physiological change that steers growth. A clearer view of this pathway’s structure and function will show how plants solved a challenge to living on land, and it will generate opportunities to improve crop plant architecture. Outreach activities will introduce young members of the public to plant responses to gravity.The experimental plan consists of three sections. The first is based on mutations that suppress the severely agravitropic growth of a lazy quadruple mutant. One of the suppressor of lazy quadruple (slq) mutants has been identified, one more is being genetically mapped. SLQ1 negatively regulates LAZY function. SLQ1 expression pattern, subcellular localization, and mechanism of action will be studied, Other SLQs will be similarly studied after they are identified. Another section is based on a functionally-relevant interaction between LAZY1 and a protein called BRXL4 discovered in a yeast two-hybrid (Y2H) screen. The Y2H method will be used to find additional interactors. A proteomic screen will independently identify LAZY1 interactors. Separate approaches used throughout the project are designed to increase the probability of obtaining convergent results. For example, genes identified in a screen for slq mutations may encode proteins that interact physically with LAZY1. The genetic, cellular, and biochemical results will be combined to create a gravity signaling framework. A third section will test mechanistic elements of the framework. The project is expected to establish an unprecedented level of molecular detail about how plants use the gravity vector to guide growth.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

大约4亿年前，当植物在陆地上定居时，它们进化出了利用地球重力矢量作为指导来确定根和芽生长方向的能力。潜在的重力传感和响应系统还没有得到很好的理解，尽管通过选择性育种对其进行的修改已经重要地塑造了今天的作物植物和树木，并且未来生产力的提高预计将伴随着更陡峭的根更好地到达水源的修改，以及当植物在高密度生产场景中拥挤时，具有更好地拦截光线的角度的枝条。该项目旨在鉴定由基因编码的蛋白质，这些蛋白质构成了拟南芥植物中的重力感应机制，拟南芥植物是一般植物的模型。该项目的基础研究表明，只有在陆地植物中发现的少量LAZY基因编码了定向根和芽的重力信号系统的关键成分。该项目将使用遗传学和生物化学领域的实验方法来寻找与LAZY蛋白一起发挥作用的基因及其蛋白质，以在细胞内创建一条途径，将重力矢量转化为引导生长的生理变化。更清楚地了解这一途径的结构和功能将显示植物如何解决在陆地上生存的挑战，并将为改善作物植物结构创造机会。外展活动将向青少年介绍植物对重力的反应。实验计划包括三个部分。第一种是基于抑制懒惰四重突变体的严重agravitropic生长的突变。其中一个惰性四重抑制基因（slq）突变体已经被鉴定出来，还有一个正在进行基因定位。SLQ 1负调节LAZY功能。将研究SLQ 1的表达模式、亚细胞定位和作用机制，其他SLQ将在鉴定后进行类似研究。另一部分是基于在酵母双杂交（Y2H）筛选中发现的LAZY1和称为BRXL4的蛋白质之间的功能相关相互作用。Y2H方法将用于寻找其他相互作用物。蛋白质组学筛选将独立鉴定LAZY1相互作用物。在整个项目中使用的单独方法旨在增加获得收敛结果的可能性。例如，在筛选slq突变中鉴定的基因可以编码与LAZY1物理相互作用的蛋白质。遗传、细胞和生物化学的结果将结合起来，创造一个重力信号框架。第三部分将测试框架的机制要素。该项目预计将建立一个前所未有的水平的分子细节，植物如何使用重力矢量，以指导growth.This奖项反映了NSF的法定使命，并已被认为是值得的支持，通过评估使用基金会的知识价值和更广泛的影响审查标准。