本项目将采用基于toehold调控的DNA链替换反应构建DNA分子计算。类比于计算机程序中的“语句”，DNA单链（或杂化双链）被用于构建计算“语句”；toehold调控的分支迁移反应，其决定了DNA单链或双链间反应的逻辑规则，在此将被用于实现类似于计算机程序设计“算法”的功能。基于上述原理，我们将构建四个“基元反应”，对应于DNA计算策略中的四个“基本函数”，并将系统研究toehold调控链替换反应的动力学特性; 考察两个或多个toehold链替换反应级联的动力学特性; 输入—输出曲线呈理想响应的反应条件及其范围。以布鲁塞尔模型体系构建多个“基本函数”级联的复杂运算程序，籍此研究输入变量和输出变量的依赖关系，并考察误差起因及误差出现的规律，同时系统研究多级“标准函数”级联效率。通过此项目，我们将提供一套标准函数及其使用基本函数构建复杂运算的DNA分子计算方法。

Based on the DNA chain displacement modulated by the toehold, the strategy for the realization of the DNA molecular computation is proposed in this project. In parallel with the “sentence” in the computational program, a set of single DNA chains (or hybridized double DNA chains) are utilized to construct the “sentences”, whereas the sequences of the branch migration reactions modulated with toehold are designed to play the similar role of “algorithm” in the established DNA computing strategies. Based on this principle, 4 “elementary reactions” that are similar to the “elementary functions” in computational program are built. To optimize these “elementary reactions”, the dynamic behaviors of the DNA chain displacement modulated by toehold, of cascades of two or more “elementary reactions”, response of the outputs to the inputs and comparison with theoretical predictions will be systematically investigated. Furthermore, in the principle of the Brusselator Model of Oscillating Chemical Reactions, the versatility and efficiency of the utilization of these “elementary functions”, the dependence of outputs on the inputs after cascading, origin of errors in the dynamic processes will be examined via the cascade of these “elementary functions” into complicated functions for the realization of some complex tasks. Under support of this fund, a set of “standard functions” and the methods for the usage of these functions in constructions of DNA molecular computing will be established.