摘要

動物的發育過程中，不同性質的細胞會分群並形成隔間(compartment boundary)。將細胞分隔至不同的區間可以確保不同的細胞訊息在適當的區間裡面傳遞，進而使該區域有適當的細胞分化(cell patterning)、形態構成(morphogenesis)與器官生成(organogenesis)。在Drosophila的翅膀器官盤(wing imaginal disc)上，細胞也會被分隔成不同區間，其中前端區間與後端區間(anterior-posterior compartment)之間會形成一條平滑的直線疆界(boundary)。這條疆界可藉由單一細胞複製成的細胞群(clone)來觀察；位在區間疆界兩側、標記綠色螢光蛋白(GFP)的細胞群因為無法跨越疆界，只能沿著疆界生長，使平滑的疆界得以被觀察。目前相信這個平滑疆界的形成是由於區間之間會生成一條肌動肌凝蛋白索(actomyosin cable)，而它的收縮作用就是造成疆界平滑的主要原因。但生成肌動肌凝蛋白索的分子機制仍然尚未解開。因此在這篇論文中，利用RNA干擾技術(RNAi)去抑制肌動蛋白的相關蛋白(actin-binding associated protein)做大規模的篩選，期望這樣的方式可以發現哪些相關蛋白參與肌動肌凝索、前端區間與後端的區間疆界的形成。實驗結果顯示，挑選出的肌動蛋白相關蛋白一旦表現量被抑制後，果蠅翅膀器官盤會有部分程度扭曲與細胞形態改變的情形產生，但這樣的情況並不影響前端區間與後端的區間疆界的生成，並且該疆界仍然保有其平滑度。

Abstract

The establishment of cellular compartment boundary is a general phenomenon in animal development. Separating cells into discrete compartment is important to prevent mislocated cell signaling and is crucial for cell patterning, morphogenesis, and organogenesis. In Drosophila wing imaginal disc, the anterior-posterior compartment boundary is characterized with straight and smooth border, which can be visualized when fluorescent-marked clone cells of one compartment touch the boundary. To date, it’s believed the formation of actomyosin cable at the A/P compartment boundary plays a key role in the establishment and maintenance of the boundary. But the molecules regulating the formation of the actomyosin cable are still unknown. Therefore, in this study we used RNAi to screen a wide-range of actin-associated actin-binding proteins and observed whether A/P boundary is affected. Although lose of function of some actin-binding proteins caused deformation of wing disc, none of these can interfere the smoothness of the A/P boundary. The result implies the effect of a single actin-binding protein might not efficient to influent boundary formation.

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