Design And Research Of Artificial Gene Circuits Based On Standardized Biological Components

Synthetic biology is an emerging discipline based on the research of traditional biology.Under the guidance of engineering ideas,it combines computer science,physics,mathematics and other disciplines to make synthetic biologists transform the original biological system or redesign new biological systems in nature.In contrast to traditional biologists,synthetic biologists study living systems from bottom to up,starting with the most basic biological parts to synthesize and assemble biological devices,and then assemble into living systems.To construct the artificial gene circuit,synthetic biologists take the standardized biological parts as its components and reprogram the cell life activities according to the existing biological rules or artificial rules to obtain the desired cell behavior.As a key technology in synthetic biology,artificial gene circuit has been developing rapidly in just two decades and has been widely concerned by people from all walks of life.The research direction of artificial gene circuit has changed from the initial basic scientific research to practical application.In addition to deepening human's understanding of the life regulation mechanism and providing methods for human's modification and redesign of life system,it also plays an important role in medicine and health,agricultural environment and industrial fermentation.The thesis first introduce synthetic biology and artificial gene circuits,then summarize the research background and significance of this thesis,and analyze the research status of synthetic biology,part engineering and artificial gene circuits at home and abroad.This part is the main premise of the research work.Only when people have a thorough understanding of these contents can they proceed with the following research work.Then the thesis introduce the basic principles and application status of synthetic biology software GenoCAD,the description of the drawing software PlasMapper,and the basic principles and application examples of biological logic gates.These are the research tools will be used in future research work,and provide technical support for the research work.After that,the thesis describe the biological gene expression regulation mechanism in detail,and describe the prokaryote gene expression regulation mechanism and eukaryote gene expression regulation mechanism respectively.This part of the content is the theoretical basis for designing artificial gene circuits,and provides a theoretical foundation for the research work.Based on this,the thesis simulate and synthesize an artificial gene circuit that regulates the expression of TetR protein on the synthetic biology software GenoCAD.In the first step,variables and context-free grammar rules based on basic biological regulation rules will be designed.Then the research work create the database in the synthetic biology software GenoCAD and add the processed biological part data.At last,the artificial gene circuit will be designed and synthesized automatically according to grammatical rules.According to its model,the thesis simplify it into a three-input logic gate to predict the result more clearly,and enter the sequence in PlasMapper to obtain the plasmid map.On the other hand,the thesis design an artificial genetic circuit with multiple stability based on the Waddington's epigenetic landscape.The three possible stable states will be analyzed and a schematic diagram will be drawn to represent the three states.This model will be designed based on the theory of cell differentiation,and may bright new ideas to the research of cell differentiation.Finally,the thesis analyze,induce,and summarize the two artificial gene circuit models the thesis design,discuss the innovation points and deficiency in this research.The thesis prospect the future development of synthetic biology and artificial gene circuits.The artificial gene circuits will play a role in more fields.