Synergistic Stabilization of Nucleic Acid Assembly by 2′-O,4′-C-Methylene-Bridged Nucleic Acid Modification and Additions of Comb-Type Cationic Copolymers
Synergistic Stabilization of Nucleic Acid Assembly by 2′-O,4′-C-Methylene-Bridged Nucleic Acid Modification and Additions of Comb-Type Cationic Copolymers
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DOI：
10.1021/bi801795z
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发表时间：
2009-04-21
期刊：
影响因子：
2.9
通讯作者：
Katayama, Takuma
中科院分区：
文献类型：
--
作者：
Torigoe, Hidetaka;Maruyama, Atushi;Katayama, Takuma
核酸组装体的稳定化对于它们广泛的潜在应用是非常重要的。已经开发了各种稳定化方法，包括化学修饰的核苷酸和杂合稳定剂的分子设计，以及不同稳定化方法的组合，以增加核酸组装体的稳定性。然而，两种稳定方法的组合并不总是产生期望的协同效应。在本研究中，为了提出选择稳定方法的合理组合的策略，我们证明了通过三链体形成寡核苷酸的2 '-O，4'-C-亚甲基桥接核酸（2 '，4'-BNA）修饰和添加聚（L-赖氨酸）-接枝-葡聚糖共聚物[聚（L-赖氨酸）接枝亲水性葡聚糖侧链]来协同稳定三链体。这些方法中的每一种都将三链体形成的结合常数增加了近2个数量级。然而，它们的动力学贡献是相当不同的。共聚物增加了缔合速率常数，而2 '，4'-BNA改性降低了三链体稳定的解离速率常数。两种稳定方法的组合使结合常数增加了近4个数量级。动力学分析表明，成功的协同稳定化是由于共聚物增加的缔合速率常数和2 '，4'-BNA修饰降低的解离速率常数之间的动力学互补性。一种稳定方法的稳定效果并不改变另一种稳定方法的稳定效果。我们建议，动力学分析的每一个稳定化效果笔nit选择一个合理的组合稳定化方法，成功的协同作用，在稳定核酸组装。
Stabilization of nucleic acid assemblies, such as duplex and triplex, is quite important for their wide variety of potential applications. Various stabilization methods, including molecular designs of chemically modified nucleotides and hybrid stabilizers, and combinations of different stabilization methods have been developed to increase stability of nucleic acid assemblies. However, combinations of two stabilizing methods have not always yielded desired synergistic effects. In the present study, to propose a strategy for selection of a rational combination of stabilizing methods, we demonstrate synergistic stabilization of triplex by 2'-O,4'-C-methylene-bridged nucleic acid (2',4'-BNA) modification of triplex-forming oligonucleotide and addition of poly(L-lysine)-graft-dextran copolymer [Poly(L-lysine) grafted with hydrophilic dextran side chains]. Each of these methods increased the binding constant for triplex formation by nearly 2 orders of magnitude. However, their kinetic contributions were quite distinct. The copolymer increased the association rate constant, whereas the 2',4'-BNA modification decreased the dissociation rate constant for triplex stabilization. The combination of both stabilizing methods increased the binding constant by nearly 4 orders of magnitude. Kinetic analyses revealed that the successful synergistic stabilization resulted from kinetic complementarity between increased association rate constants by the copolymer and decreased dissociation rate constants by the 2',4'-BNA modification. The stabilizing effect of one stabilization method did not alter that of the other stabilization method. We propose that kinetic analyses of each stabilizing effect pen-nit selection of a rational combination of stabilizing methods for successful synergy in stabilizing nucleic acid assemblies.