An Integrative Analysis of MAPK Signaling in Budding Yeast

描述（申请人提供）：调节芽殖酵母S.酿酒酵母中的丝裂原活化蛋白激酶（MAPK）级联反应是一种典型的信号转导途径，对MAPK级联反应的分析使人们对MAPK级联反应的结构和功能有了更深入的了解。已经开发了大量的遗传和分子生物学工具，这些工具继续使该途径成为一个非常有吸引力的系统，用于逐步完善对细胞微环境信号如何转化为基因转录和细胞形态的明确变化的理解。然而，我们对这一重要途径的理解还远未完成，这在很大程度上是由于缺乏实验工具来分析在梯度感应和趋化性的更多生理背景下的途径活性，以及饱和信息素梯度（默认响应）中的连续投影形成，而不是对空间均匀信息素浓度的相对短期响应。在这个应用中，我们建议使用新的实验设计和微加工设备的梯度感应和默认响应表型的背景下，研究交配途径。我们建议调查的途径活动的各种修饰剂的作用，特别关注的支架蛋白和各种负调节。我们还将探索信息素途径和其他MAPK途径之间的串扰机制，也依赖于新的实验技术。这些定量实验分析的结果将被整合到一个全面的计算模型的MAPK途径激活芽殖酵母。MAPK通路在不同物种中的保守性以及这些通路在各种人类病理学中的特殊重要性使得这项研究对我们了解人类健康和疾病特别重要。公共卫生相关性：这个应用程序的重点是系统的方法，信号转导的原型和最研究的途径之一，在酵母中的交配途径。尽管它表面上很简单，但这条途径调节了大量的细胞反应，从细胞形态的变化和定向细胞生长，到周期性形态发生和数百个基因的表达。我们建议使用一组新的方法来研究途径可以控制这组不同的表型反应的方式，并建立一个定量的途径功能的理解。我们预计，我们的研究结果将提供有关酵母和高等生物中其他途径功能的信息。

DESCRIPTION (provided by applicant): The mating response pathway regulating fusion of two haploid cells of the budding yeast S. cerevisiae or activated in response to exogenously added pheromones has been a prototypical signal transduction pathway, whose analysis led to multiple important insights into the structure and function of mitogen-activated protein kinase (MAPK) cascades. A vast collection of genetic and molecular biology tools have been developed that continue to make this pathway a very attractive system for developing a progressively refined understanding of how the signals from the cell microenvironment are converted into well defined changes in gene transcription and cell morphology. However, our understanding of this important pathway is far from complete, in large part due to the lack of experimental tools for analysis of the pathway activity in more physiological contexts of gradient sensing and chemotropism, and the sequential projection formation in saturating pheromone gradients (the default response), as opposed to the relatively short term responses to spatially homogeneous pheromone concentrations. In this application, we propose to study the mating pathway within the contexts of gradient sensing and default response phenotypes using novel experimental designs and microfabricated devices. We propose to investigate the role of various modifiers of pathway activity, with a particular focus on the scaffold protein and various negative regulators. We will also explore the mechanisms of cross-talk between the pheromone pathway and other MAPK pathways, also relying on the novel experimental technology. The results of these quantitative experimental analyses will be integrated into a comprehensive computational model of the MAPK pathways activated in budding yeast. Conservation of MAPK pathways across species and the particular importance of these pathways in various human pathologies make this research especially significant for our understanding of human health and disease. PUBLIC HEALTH RELEVANCE: This application is focused on the systems approach to signal transduction in one of the prototypical and most studied pathways, the mating pathway in yeast. In spite of its apparent simplicity, this pathway regulates a plethora of cell responses, from changes in cell morphology and directed cell growth, to periodic morphogenesis and expression of hundreds of genes. We propose using a set of novel approaches to investigate the way the pathway can control this diverse set of phenotypic responses and build a quantitative understanding of the pathway function. We anticipate that our findings will be informative about the function of other pathways in yeast and higher organisms.