Characterization of signaling pathways involved in the homeostasis of the endosomal apparatus

内体装置稳态相关信号通路的表征

• 批准号: 155751-2006
• 负责人: Faure, Robert
• 金额: $ 2.06万
• 依托单位: Université Laval
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2008
• 资助国家: 加拿大
• 起止时间: 2008-01-01 至 2009-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=391840
• 关键词: Characterization; signaling; pathways; involved; homeostasis

DESCRIPTION OF THE PROJECT: After insulin or EGF binding, tyrosine kinase-activated receptors (RTKs) internalize into the endosomal apparatus (EA). In endosomes, the signal can be amplified, selected, or terminated. Conversely, it is perceived that the EA controls the intracellular location and thus, the response of RTKs. This project is focused on the characterization of signaling mechanisms controlling the homeostasis of the EA. ORIGINALITY: During the last funding periods, we generated a library of hepatic endosomal proteins that are tyrosine phosphorylated in vivo. These proteins are being identified progressively and new mechanisms are characterized. We will focus here on the c-src/DPPIV pathway. OBJECTIVES: 1) To characterize DPP IV tyrosine-phosphosites as well as analyze the endosomal proteins associated with DPPIV and c-src. 2) To characterize the mechanism of action c-src in endosomes. 3) To pursue the proteomic characterization of endosomal fractions. SCIENTIFIC APPROACH: 1) Insulin, and presumably EGF, have the capacity to sort DPP IV to src-containing compartments. Here, DPPIV is tyrosine-phosphorylated. DPPIV phosphosites as well as the organization of the luminal c-src platform will be characterized in the different endosomal compartments. Fractionation in concert with biochemical approaches will be validated by confocal microscopy. 2) Highly purified hepatic endosomal fractions were characterized previously and we initiated a proteomic survey by identifying proteins present in a fraction comprised of Golgi/endosomes. We will pursue here, a systematic differential identification of proteins in early versus late vesicular compartments following insulin and EGF stimulation. SIGNIFICANCE; This program aims to clarify both the functional connections among elements of the endocytic pathway as well as elucidate mechanisms by which surface outputs are integrated.

项目描述：胰岛素或EGF结合后，酪氨酸激酶激活受体（RTK）内化到内体装置（EA）中。在核内体中，信号可以被放大、选择或终止。相反，据认为，EA控制细胞内的位置，因此，RTK的响应。该项目的重点是表征控制EA稳态的信号机制。来源：在上一个资助期，我们生成了一个在体内酪氨酸磷酸化的肝内体蛋白质文库。这些蛋白质正在被逐步鉴定，新的机制正在被表征。我们将重点关注c-src/DPPIV通路。目的：1）研究DPPIV酪氨酸磷酸化位点，并分析与DPPIV和c-src相关的内体蛋白。2)研究c-src在内体中的作用机制。3)研究内体组分的蛋白质组学特征。科学方法：1）胰岛素和可能的EGF具有将DPP IV分选到含src的隔室的能力。在这里，DPPIV是酪氨酸磷酸化的。DPPIV磷酸化位点以及管腔c-src平台的组织将在不同的内体隔室中表征。与生化方法相结合的分级将通过共聚焦显微镜进行验证。2)高度纯化的肝内体组分的特点是以前，我们开始了蛋白质组学调查，确定蛋白质存在于一个部分组成的高尔基体/内体。我们将追求在这里，一个系统的差异识别蛋白质在早期与晚期囊泡隔室胰岛素和EGF刺激后。意义;该项目旨在阐明内吞途径元件之间的功能联系，以及阐明表面输出整合的机制。