Echinoid（Ed）是Adherens Junctions（AJs）上的細胞黏著分子，透過其細胞外的結構Ed 能夠和相鄰細胞上的Ed 進行同嗜性作用，而在細胞內則是透過 Canoe 與 Actin filament 產生交互作用。Ed 與 DE-Cadherin 會表現於 Adherens Junctions（AJs）上，共同調節細胞黏著性 (Cell adhesion) 。在過去的研究中，當我們在果蠅的翅膀成蟲盤上表現 Ed mutant clone 時，wild-type 細胞會產誘導肌動蛋白索形成在兩群細胞之交界，進而形成細胞分選 (Cell sorting) 。 且透過實驗，我們了解 Ed intracellular domain 的不對稱分布是誘導肌動蛋白索形成之關鍵。在此篇研究中，我們設計了不同長度的 Ed intracellular domain 的 truncated forms ，並透過 UAS-GAL4 系統以及 ed RNAi 清除掉內源性的 Ed ，再利用Recombination 產生mitotic clones ，觀察當不同的 truncated forms 呈現不對稱分布時，兩群細胞之交界的肌動蛋白索形成的影響。
在本次實驗中，我們發現過量表現 truncated Ed 會導致組織變形，且每一段 motif 對於肌動蛋白索形成皆有影響，更詳細的關聯性可能與蛋白質結構有關。

Echinoid (Ed) is a cell adhesion molecule (CAM) of Adherens Junctions (AJs) where it cooperates with DE-cadherin to mediate cell adhesion and Ed intracellular domain links to actin filament through Canoe. In the previous studies, we found that wild-type cells have contribute to actin cables assembled in the interface between WT cells and Ed mutant cells as we generate Ed mutant clone in the wing imaginal disc. Ed is involved in mediating the formation of actin cables in mutant clones. However, which part of Ed affects the formation of actin cables is unknown. To examine this, we designed different truncated forms of Ed intracellular domain and determined the functional domain which was related to the formation of actin cables. By using UAS-GAL4 system and RNA interference of ed, we spatially and temporally removed endogenous ed and generated mitotic clones of Ed truncated forms to observe the formation of actin cables on the boundary between Ed- clone and Ed truncated form clone in the wing imaginal discs.
We found that overexpression of truncated Ed by nub-gal4 causes the deformation of wing punch. According to our experiment, actin cables assembly in Echinoid-mediated cell sorting is affected by each motif which might regulates the process of protein folding.

Contents 1
Introduction 2
Materials & Methods 4
Fly Stocks 4
Mosaic Analyses and Ectopic Expression 4
Immunohistochemistry 6
Quantitative analysis 7
Result and Discussion 8
Figures 10
References 22

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