D型肝炎病毒抗原蛋白胺端區域之核酸監護子活性的研究

The study of the nucleic acid chaperone activity of the N-terminal domain of hepatitis delta antigen

陳幼襦(You-Ju Chen)

指導教授 ： 吳惠南 博士

臺北醫學大學/醫學院/細胞及分子生物研究所/碩士(2004年)

摘要

D型肝炎病毒抗原蛋白的胺端1到88個胺基酸(簡稱為NdAg)具有核酸堅護子的活性，我的研究在探討NdAg在執行核酸堅護子活性時的機制。我利用melting temperature (Tm) analysis分析以化學法合成DNA oligomers所形成互補序列間的穩定度，再選取特定的DNA oligomers進行核酸監護子的活性分析。我發現NdAg能選擇性地促使較高和較低Tm值範圍的DNA oligomers形成較穩定的雙股，另外NdAg對不同濃度的DNA oligomers都具有類似的活性。NdAg亦能促使股交換反應，讓可和底股形成雙股的頂股取代原較不穩定雙股的頂股。然而NdAg執行股交換反應時並沒有方相性。

關鍵字

核酸監護子

並列摘要

The N-terminal domain, which contains amino acids # 1-88, of hepatitis D antigen possesses a nucleic acid chaperon activity. In this study I investigated the molecular mechanism of the nucleic acid chaperon activity of NdAg. I utilized the Tm analysis to examine the thermal stability of chemically synthesized DNA duplexes, and then choosed specific DNA oligomers to analyze the nucleic acid chaperon activity of NdAg, namely the selective strand annealing activity and the selective strand exchange activity. I found that NdAg facilitates the formation of more stable duplex among competing sequences of high as well as low Tm value ranges, and NdAg effects in different DNA oligomer concentrations. Besides, NdAg also promotes strand exchange for the formation of more stable DNA duplex, and the strand displacement process does not have a specific polarity.

並列關鍵字

nucleic acid chaperone

參考文獻

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Huang, Z. S., Su, W. H., Wang. J. L., and Wu, H. N. (2003) Selective Strand Annealing and Selective Strand Exchange Promoted by the N-terminal Domain of Hepatitis Delta Antigen. J. Biol. Chem. 278, 5685-5693