分析phostensin 對內吞運輸作用的影響

Analysis of the Effect of Phostensin on the Endocytic Transportation

翁家儂(Chan-Nung Weng)

指導教授 ： 黃憲斌

國立中正大學/理學院/生命科學系生物醫學研究所/碩士(2015年)

摘要

Phostensin被鑑定為是第一型蛋白質磷酸水解酶 (PP1) 及F-肌動蛋白細胞骨架的結合蛋白，由KIAA1949基因轉錄。EHD proteins是調節特定內吞循環步驟的關鍵調控者。而EHD proteins的G-domain是使EHD proteins 能夠進行寡聚化(oligomerization)的重要區域。在實驗室先前研究指出，phostensin會與EHD proteins的G-domain結合，所以我們想知道此交互作用是否會去干擾 EHD proteins 的寡聚化，進而影響內吞運輸(endocytic transportation)。Hela細胞不會表達phostensin。在我的研究中，先在Hela細胞中過度表達phostensin，再利用流式細胞儀去分析phostensin對transferrin內吞運輸的影響。我的研究結果指出過度表達phostensin會減緩transferrin的內吞運輸速率。

關鍵字

蛋白質磷酸化水解酶 ； 內吞循環途徑 ； 內吞作用

並列摘要

Phostensin, a protein phosphatase-1 and F-actin cytoskeleton targeting protein, is encoded by KIAA1949. The preliminary results in our laboratory have demonstrated that phostensin binds to EHD proteins. EHD proteins play a critical role in regulation of endoctyic transport. Phostensin binds to the G domain of EHD proteins. This interaction may block the oligomerization of EHD proteins, in turn affecting the endocytic recycling. Our early study using western blotting has demonstrated that HeLa cell do not express phostensin. In my study, I overexpressed phostensin in HeLa cell and use flow cytometer to analyze the effect of phostensin on the endocytic transport of transferrin. Our results indicated that overexpression of phostensin can attenuate the endocytic transportation of transferrin.

並列關鍵字

EHD protein ； endocytic transportation ； phostensin

參考文獻

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