2020-08-012024-05-18https://scholars.lib.ntu.edu.tw/handle/123456789/699639摘要：上皮生長因子受器(EGFR)的活化對於生物體的發育、組織的生理恆定以及免疫系統扮演著至關重要的角色，上皮生長因子受器訊息傳遞路徑的失衡常與許多種類癌症疾病有很大的關聯性存在。上皮生長因子受器的泛素化作用以及胞內體的運輸是調控上皮生長因子受器訊息傳遞路徑如何適當關閉的重要機制。至今，CBL蛋白是唯一被研究了解參與在上皮生長因子受器泛素化作用的E3泛素化酵素。然而，無法召聚CBL蛋白作用的上皮生長因子受器Y1045突變蛋白，在上皮生長因子刺激之後，仍然保有相當程度的泛素化作用，顯示著可能還有其他的E3泛素化酵素參與了上皮生長因子受器的泛素化作用及其經由溶&#37238;體的降解作用。一個屬於zinc finger/RING finger類型的泛素化酵素，ZNRF1，原先是在周邊神經受損之後因表現量上升被發現，ZNRF1也被發現參與瓦勒氏神經纖維變性的過程。我們初步結果顯示ZNRF1參與了上皮生長因子受器降解以及訊息傳遞路徑的調控。ZNRF1調控上皮生長因子受器降解的過程需要其E3泛素化酵素的活性以及溶&#37238;體參與的機制。此外，ZNRF1調控了上皮生長因子刺激之後，受器從胞內體到溶&#37238;體之間的運輸作用。我們的研究結果顯示ZNRF1透過調控上皮生長因子受器在細胞內的運輸及降解，進而控制受器下游的訊息傳遞路徑，及影響了其相關生理上的功能。這個研究將會探討ZNRF1如何調控上皮生長因子受器在細胞內的運輸以及如何對上皮生長因子受器所參與的癌症腫瘤發生產生影響。 這項研究包含以下的研究目標： 目標一：探討ZNRF1是如何調控上皮生長因子受器在細胞內的運輸作用 目標二：研究活化的上皮生長因子受器如何激活ZNRF1的機制 目標三：探討ZNRF1對於上皮生長因子受器介導的體內外腫瘤發生所扮演的角色 這項研究將會提供我們更多對上皮生長因子受器的訊息傳遞調控機制以及其相關生理功能的知識，並有助於提升我們瞭解及增強對於包括癌症在內所有因上皮生長因子受器訊息失控引起疾病的治療。 <br> Abstract: Activation of the epidermal growth factor receptor (EGFR) is crucial for development, tissue homeostasis, and immunity, and dysregulation of EGFR signaling is associated with numerous diseases, including cancers. EGFR ubiquitination and endosomal trafficking are key events that regulate the termination of EGFR signaling. Until now, Casitas B-lineage lymphoma (CBL) is the only known E3 ubiquitin ligase that mediates EGFR ubiquitination and trafficking. However, the EGFRY1045F mutant, which is unable to directly recruit CBL, is still modified by ubiquitination, albeit to a lesser extent, after EGF stimulation, suggesting that there might be additional E3 ubiquitin ligases involved in EGFR ubiquitination and lysosomal degradation. ZNRF1, a zinc finger/RING finger type E3 ubiquitin ligase, was shown to be up-regulated in Schwann cells after peripheral nerve injury and promote Wallerian degeneration. Our preliminary results demonstrate that ZNRF1 controls ligand-induced EGFR degradation and signaling. ZNRF1-mediated EGFR degradation requires its E3 ligase activity and the lysosome-mediated mechanism. In addition, ZNRF1 regulates EGFR trafficking from the endosomes to the lysosomes after EGF treatment. Our data suggest that ZNRF1 regulates EGFR endosomal trafficking to control its downstream signaling and related physiological functions. This proposal will explore the impacts of ZNRF1 on ligand-induced EGFR trafficking and EGFR-mediated tumorigenesis. This proposal consists of the following specific aims: Aim 1: To examine how ZNRF1 regulates ligand-induced EGFR trafficking. Aim 2: To explore the mechanism by which ZNRF1 is activated upon EGFR activation. Aim 3: To characterize the role of ZNRF1 in EGFR-mediated tumorigenesis in vitro and in vivo. This study will provide new insights into the regulation of EGFR signaling and related physiological functions. The knowledge generated from this project should contribute to advancing the understanding and therapy of diseases caused by uncontrolled EGFR signaling including cancers.泛素化胞內運輸胞內體分選轉運溶&#37238體腫瘤發生Ubiquitinationtraffickingendosomal sortinglysosometumorigenesis