Regulation of developmental signaling by beta-arrestin

这项研究的长期目标是研究后生动物发育过程中控制细胞通讯的机制。β-抑制蛋白最近已经作为几种信号系统的多功能调节剂出现。β-抑制蛋白通过与特定的信号传导组分结合并调节细胞内信号的持续时间、放大和路由来控制信号传导网络。由于它们在信号传导网络中的中心位置，β-抑制蛋白与多种人类疾病有关，例如精神分裂症、抑郁症、癌症、心脏病、哮喘和糖尿病。尽管对β-arrestins的信号传导活动进行了大量的研究，但对它们在生物体发育中的生物学作用知之甚少。目前的建议的目标是调查如何在果蝇，库尔茨（Krz），一个单一的β-arrestin控制两个重要的发育信号网络。在缺乏Krz的果蝇胚胎中获得的初步数据表明，Krz蛋白抑制了在早期发育中活跃的两种信号通路的功能：受体酪氨酸激酶Torso/MAPK和Toll/NF-B。这两种途径在几种人类疾病如癌症和免疫性疾病中具有临床相关性。果蝇作为一种遗传上易于处理且可量化的系统，具有独特的优势，可以剖析β-抑制蛋白Krz在这些途径中的作用。本论文的主要目的有两个：1）研究Krz与MAPK、ERK的相互作用在受体酪氨酸激酶信号转导中的作用。这个目标的主要目的是确定区域的Krz蛋白负责其与ERK的相互作用的生化筛选程序，并测试这些区域的功能的重要性，在受体酪氨酸激酶调节使用体内功能测定。一种创新的定量成像方法将被用来确定所确定的Krz-ERK接触区域的相对重要性，所观察到的抑制作用的Krz对MAPK信号。2)探讨Krz对NF- B的调控机制。遗传学和新的蛋白质组学策略的组合将被用来确定可能的模式的调节收费信号的Krz。拟议研究的整体优势在于整合遗传学，蛋白质组学以及mRNA和蛋白质表达模式的定量测量。这种多层次的方法，这是牢固地植根于功能在体内的研究，可能会推进我们的知识的机制，β-arrestins控制发育信号通路，并可能为设计β-arrestin定向疗法的新途径。

The long term goal of the proposed research is to investigate the mechanisms that control cell communication during metazoan development. beta-arrestin proteins have recently emerged as multifunctional regulators of several signaling systems. beta-arrestins control signaling networks by associating with specific signaling components and modulating the duration, amplification, and routing of signals inside the cells. Because of their central position in signaling networks, beta-arrestins have been implicated in multiple human diseases, such as schizophrenia, depression, cancer, heart disease, asthma, and diabetes. Despite a large body of work on the signaling activities of beta-arrestins, their biological role in organism development is poorly understood. The goal of the current proposal is to investigate how a single beta-arrestin in Drosophila, Kurtz (Krz), controls two important developmental signaling networks. Preliminary data obtained in Drosophila embryos lacking krz suggest that the Krz protein inhibits the function of two signaling pathways that are active in early development: the receptor tyrosine kinase Torso/MAPK and Toll/NF-κB. Both of these pathways have clinical relevance in several human diseases such as cancer and immunological disorders. Drosophila offers a unique advantage as a genetically tractable and quantifiable system to dissect the role of beta-arrestin Krz in these pathways. Two specific aims will be pursued: 1) To study the role of interactions between Krz and MAPK ERK in the regulation of receptor tyrosine kinase signaling. The main objective of this aim is to identify regions in the Krz protein responsible for its interaction with ERK in a biochemical screening procedure, and to test the functional importance of these regions in receptor tyrosine kinase regulation using in vivo functional assays. An innovative quantitative imaging approach will be used to determine the relative importance of the identified Krz-ERK contact regions for the observed inhibitory effects of Krz on MAPK signaling. 2) To study the mechanisms of NF-κB regulation by Krz. A combination of genetics and novel proteomics strategies will be used to determine the likely mode of regulation of Toll signaling by Krz. The overall strength of the proposed research lies in an integration of genetics, proteomics, and quantitative measurements of mRNA and protein expression patterns. Such a multi-level approach, which is firmly rooted in functional in vivo studies, will likely advance our knowledge of the mechanisms used by beta-arrestins to control developmental signaling pathways, and may suggest new avenues for designing beta-arrestin-directed therapies.