2020-01-012024-05-18https://scholars.lib.ntu.edu.tw/handle/123456789/700134摘要：細胞表面脂質筏(脂類微環境)參與訊息傳遞，而脂質筏與蛋白質的交互作用則是啟動訊息傳遞鏈的開關。探討脂質筏結構與其性質的顯微觀察，對複雜生化現象的耙梳，可提供微觀層次的資訊與學理基礎。雖然目前已有和脂質筏相關的訊息傳遞路徑之研究報導，例如過敏反應時的IgE訊息傳遞、T細胞活化以及GDFN (神經膠質細胞株衍生神經滋養因子)的訊號傳遞，但這些實驗需要以相當繁複困難的方法將脂質筏自原始狀態純化分離，分離過程中無可避免的破壞脂質筏或嵌於其中的蛋白質受體的結構；而運用螢光顯微技術以觀察脂筏之形成則缺乏獲得即時資訊的彈性。本整合研究計畫的目標為(1)發展無須分離脂筏且可即時觀察的AFM (原子力顯微鏡)技術，擬經由AFM對脂筏結構與特性的顯微觀察所獲得的資訊，運用於(2)研究參與疾病發展和免疫反應的細胞表面受體之分子機制。即時資訊有助於掌握訊號傳遞的進程與時序，在治療疾病及刺激免疫反應，可以在適當時間點研究細胞內訊息蛋白的消長，以探討其分子機制。本計畫在初期將觀察典型的體系，以文獻資訊檢視AFM獲得的結構資訊。擬觀察惡性癌細胞表面過度表現的alpha v beta 3整合蛋白受體，該受體所開啟的訊息傳遞路徑的重要性在於癌組織的血管新生及腫瘤轉移。這個階段旨在磨鍊成員的AFM操作技術，並進而發展適合細胞觀察的AFM方法學。計畫中後期將研究其他種類的整合蛋白受體，例如和免疫細胞活化相關的B細胞受體/T細胞受體，以及參與癌症發展的生長因子受體。我們期望所獲得的資訊能夠幫助我們從分子層級來解釋複雜的生化現象，長期而言，希望對藥物設計及臨床治療有所貢獻。<br> Abstract: It is clear that lipid micro-environments on the cell surface, so-called lipid rafts, take part in the process of signal transduction cascades that is known to be initiated by protein-protein interactions. The size and composition of lipid rafts (with or without partitioning of proteins), and the raft affinity of a given protein, can be altered in response to intra- or extracellular stimuli. In addition, crosslinking of signaling protein receptors may also increase their affinity for rafts. Several raft dependent signaling processes have been previously discussed, including IgE signaling during the allergic response, T-cell activation, and GDNF (Glial cell-line derived neurotrophic factor) signaling. It is apparently too challenging to isolate lipid rafts in their native state, and too difficult to observe them by typical optical microscopic techniques. The goals of our integrated studies are (1) to establish an AFM (atomic force microscopy) platform to investigate the structures and characteristics, and (2) to unravel molecular mechanisms of cell surface receptors that operate in disease-developing responses and immunological responses. This proposal focuses on the signaling pathways initiated by the receptor (alpha-v beta-3 integrin) for the invasion of cancerous cells that play a central role in angiogenesis and tumor metastasis and serves as a model for other types of integrin receptors. The developed method may be applicable to other receptors, including B-cell receptor/T-cell receptor for immune cells activation, and growth factor receptors involved in cancer development. The information obtained shall allow us to elucidate complex biological systems on the molecular level, and also has important impact on drug design and clinical therapies.基礎物質作用力分子探針分子機械奈米複合半導體臨場量測fundamental interactions at the atomic/molecular levelsmolecular probemolecular machinenanocomposite semiconductorin-situ measurements