English  |  正體中文  |  简体中文  |  Items with full text/Total items : 43312/67235
Visitors : 2106812      Online Users : 5
RC Version 5.0 © Powered By DSPACE, MIT. Enhanced by NTU/NCHU Library IR team.
National Chung Hsing University Institutional Repository - NCHUIR > 生命科學院 > 生物化學研究所 > 依資料類型分類 > 期刊論文 >  Binding of actinomycin D to single-stranded DNA of sequence motifs d(TGTCT(n)G) and d(TGT(n)GTCT)

Please use this identifier to cite or link to this item: http://nchuir.lib.nchu.edu.tw/handle/309270000/130839

標題: Binding of actinomycin D to single-stranded DNA of sequence motifs d(TGTCT(n)G) and d(TGT(n)GTCT)
作者: Chen, F.M.;Sha, F.;Chin, K.H.;Chou, S.H.
周三和;秦可欣
關鍵字: tetranucleotide sequences;gpc sites;model;drug;specificities;complex;xgcy
日期: 2003
Issue Date: 2012-12-07 16:08:59 (UTC+8)
關連: Biophysical Journal, Volume 84, Issue 1, Page(s) 432-439.
摘要: Our recent binding studies with oligomers derived from base replacements on d(CGTCGTCG) had led to the finding that actinomycin D (ACTD) binds strongly to d(TGTCATTG) of apparent single-stranded conformation without GpG sequence. A fold-back binding model was speculated in which the planar phenoxazone inserts at the GTC site with a loop-out T base whereas the G base at the T-terminus folds back to form a basepair with the internal C and stacks on the opposite face of the chromophore. To provide a more concrete support for such a model, ACTID equilibrium binding studies were carried, out and the results are reported herein on oligomers of sequence motifs d(TGTCT(n)G) and d(TGT(n)GTC). These oligomers are not expected to form dimeric duplexes and contain no canonical GpC sequences. It was found that ACTD binds strongly to d(TGTCTTTTG), d(TGTTTTGTC), and d(TGTTTTTGTC), all exhibiting 1:1 drug/strand binding stoichiometry. The fold-back binding model with displaced T base is further supported by the finding that appending TC and TCA at the T-terminus of d(TGTCTTTTG) results in oligomers that exhibit enhanced ACTD affinities, consequence of the added basepairing to facilitate the hairpin formation of d(TGTCTTTTGTG) and d(TGTCTTTTGTCA) in stabilizing the GTC/GTC binding site for juxtaposing the two G bases for easy stacking on both faces of the phenoxazone chromophore. Further support comes from the observation. of considerable reduction in ACTD affinity when GTC is replaced by GTTC in an oligomer, in line with the reasoning that displacing two T bases to form a bulge for ACTD binding is more difficult than displacing a single base. Based on the elucidated binding principle of phenoxazone ring requiring its opposite faces to be stacked by the 3'-sides of two G bases for tight ACTD binding, several oligonucleotide sequences have been designed and found to bind well.
Relation: Biophysical Journal
Appears in Collections:[依資料類型分類] 期刊論文
[依教師分類] 周三和

Files in This Item:

There are no files associated with this item.



 


學術資源

著作權聲明

本網站為收錄中興大學學術著作及學術產出,已積極向著作權人取得全文授權,並盡力防止侵害著作權人之權益。如仍發現本網站之數位內容有侵害著作權人權益情事者,請權利人通知本網站維護人員,將盡速為您處理。

本網站之數位內容為國立中興大學所收錄之機構典藏,無償提供學術研究與公眾教育等公益性使用。

聯絡網站維護人員:wyhuang@nchu.edu.tw,04-22840290 # 412。

DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU/NCHU Library IR team Copyright ©   - Feedback