脂聯素(adiponectin)是一種由脂肪組織所分泌的細胞激素(adipokines)，由於它能促進個體對胰島素的敏感度，對於第二型糖尿病、冠狀動脈疾病以及高血壓等代謝症候群具有顯著得改善效果，因此在近幾年吸引了許多人投入研究。然而脂聯素的訊息傳遞路徑仍充滿許多未知，因此在本研究當中我們試圖找出脂聯素的訊息傳遞路徑中能與第一型脂聯素受體(AdipoR1)交互作用的傳導蛋白。我們採用了酵母雙雜交(yeast two hybrid)以及免疫沉澱(immunoprecipitation)兩種方法，其中從免疫沉澱實驗中的質譜儀定序結果中，我們找到穿膜蛋白43(TMEM 43)。我們發現在螢光顯微鏡下可觀察到細胞中標記紅螢光蛋白的重組TMEM43(RFP-TMEM43)與標記綠螢光蛋白的重組AdipoR1(GFP-AdipoR1)的分布似乎有共定位的現象。進一步共免疫沉澱的實驗加以驗證也顯示了標記FLAG的重組TMEM43 (FLAG-TMEM43) 與標記綠螢光蛋白的重組AdipoR1(GFP-AdipoR1) 之間有顯著的交互作用。另外在功能方面，因為之前有報告發現TMEM43的表現會受到伽瑪型過氧化體增殖劑活化受器(PPAR-γ)所活化。而過氧化體增殖劑活化受器已被確定和脂聯素的訊息傳遞路徑有關，因此我們假設TMEM43可能透過過氧化體增殖劑活化受器的調節而涉及脂聯素的訊息傳遞路徑中。期待本研究能釐清脂聯素的訊息傳遞路徑，以利於代謝症候群治療方法的未來發展。

Adiponectin which is one of adipokines has attracted much attention in these years because of its significant effects to improve metabolic syndromes, such as type 2 diabetes, coronary artery disease, and hypertension. Nevertheless, the signal transduction pathway of adiponectin remains largely unknown. Utilizing two approaches, yeast two hybrid and immunoprecipitation, we began to explore the AdipoR1 binding partners which might be involved in adiponectin/AdipoR1 signaling pathway. TMEM43 was found in the immunoprecipitation recovery database of MS-SPEC results. Expression of RFP-TMEM43 and GFP-AdipoR1 in many cell types seems to colocalize under fluorescent microscope. Coimmunoprecipitation experiments were further employed to demonstrate that FLAG-TMEM43 significantly binds to GFP-AdipoR1. Previous studies considered that TMEM43 might be activated by PPAR-γ which involved in regulating cellular lipid metabolism in adiponectin/AdipoR1 signaling pathway. It is plausible that TMEM43 could play an important role in adiponectin/AdipoR1/PPARs signaling pathway. Hopefully, this study could provide new therapeutic target(s) for the drugs development to ameliorate metabolism related diseases.

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