細胞骨架(cytoskeleton)在真核細胞(eukaryotic cells)中是一種動態平衡(dynamic)並且由許多蛋白質組成的複雜網路型結構，主要由三大成員所構成：microtubules，intermediate filaments 以及actin filaments。細胞骨架的主要供功能是維持與改變細胞的形狀與行為，並藉由與其他相關蛋白質的交互作用進而調控細胞的附著(adhesion)、擴張(spreading)與移行(migration)。然而細胞骨架相關蛋白也參與了部分訊息傳遞步驟，藉由吸引許多相關蛋白質聚集，並與一些在細胞膜周圍的受器蛋白產生交互作用，進而對細胞外或是細胞內的環境刺激做出反應。其中一個細胞骨架相關蛋白質palladin在調控細胞貼附與細胞張力絲(stress fibers)的形成中扮演重要的角色。常見的幾種同功異構型palladin，依其分子量可分為200kDa，140kDa以及90-92kDa，在先前有關palladin的蛋白質交互作用之相關研究多侷限於90-92kDa異構型palladin，反而對於 palladin 全長 200kDa 異構型扣除掉 90-92kDa 異構型之後剩下的 N’ 端片段[以下簡稱 palladin(200~90) ] 相關的研究極少，於是我們針對這個區域，利用酵母菌雙雜合系統(Yeast two Hybrid system，Y2H)以及免疫沉澱(Immunoprecipitation, IP)進行一連串的實驗與探討。

The cytoskeleton of eukaryotic cells is a dynamic and complex network which containing three major members: microtubules, intermediate filaments and actin filaments. An important role of cytoskeleton is to maintain the cell shape and to form complex structures to regulate cell adhesion and migration by interacting with other proteins. The cytoskeleton also participates part of signal transductions to reflect inner- and outer- cell environmental stimulates by recruit cytoskeleton associated proteins and interact with receptor proteins near the cell membrane. One of cytoskeleton-associated proteins, palladin, plays an important role in regulating cell adhesion and the formation of stress fibers. There are three kinds of isoforms: 200kDa, 140kDa, and 90-92kDa. Most literature of protein-protein interaction of palladin are only about palladin 90-92kDa isform. There is no study of N’-terminal interacting partners of palladin 200 kDa isoform. So we use yeast two hybrid system and immunoprecipitation to characterize the N’-terminal interacting partners of palladin 200 kDa isoform.

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