合成生物学新技术在基因表达精确调控和提高脂肪酸合成效率方面的应用

doi:10.16183/j.cnki.jsjtu.2019.01.001

摘要/Abstract

摘要： 基因表达是生物体最重要的生理活动之一，而对基因表达进行精确的人工调控则是控制生物体蛋白合成以及生理活动的重要手段.上海交通大学国际基因工程机器大赛(International Genetically Engineered Machine Competition, iGEM)团队自2009年参赛以来，多次应用合成生物学方法成功创建了稀有密码子开关、细胞膜支架和光控CRISPR干扰(CRISPRi)系统3种新型基因调控元件.通过在目的基因的起始密码子后插入合适数量的稀有密码子，对基因表达进行精确调节，调控一个多酶体系在最适化学计量比上进行反应；细胞膜支架可将目标蛋白固定在细胞内膜上，缩短不同蛋白之间的空间距离，加速酶催化反应速率；光控CRISPRi系统则创新性地将生物感光系统与新兴的CRISPRi技术相结合，通过光信号在转录水平上精确调控生物体内源基因的表达.这3项新技术在大肠杆菌脂肪酸合成方面均得到了成功的应用，从而提高了脂肪酸的合成量和分泌效率.

关键词: 基因表达调控, 脂肪酸, 稀有密码子, 细胞膜支架, CRISPR干扰

Abstract: Gene expression is one of the most essential activities in life, so exerting the accurate artificial regulation on gene expression is an important method to manipulate protein synthesis and physiological activity. The International Genetically Engineered Machine Competition (iGEM) team from Shanghai Jiao Tong University has exploited three types of innovative genetic regulatory devices based on the concept of synthetic biology since the first participation in 2009, including rare codon switch, membrane scaffold and light-controlled CRISPR interference (CRISPRi) system. By inserting an appropriate number of rare codon right after the start codon of target genes, the precise regulation of gene expression can be achieved so as to manipulate the reaction of a multi-enzyme system in its optimal stoichiometric ratio. Membrane scaffold can anchor target proteins on the cell inner membrane, which shortens the space distance between different proteins, and accelerates the enzymatic reaction rate, while light-controlled CRISPRi system has innovatively combined biological light sensor and emerging CRISPRi technique to achieve the precise regulation of endogenous genes expression on transcriptional level through light signal. These new technologies have favorable applications in improving the fatty acid synthesis and secretion efficiency in Escherichia coli.

Key words: gene expression regulation, fatty acid, rare codon, membrane scaffold, CRISPR interference (CRISPRi)

中图分类号:

Q 819

王毓舒, 贺林, 马钢. 合成生物学新技术在基因表达精确调控和提高脂肪酸合成效率方面的应用[J]. 上海交通大学学报, 2019, 53(1): 1-10.

WANG Yushu, HE Lin, MA Gang. The Application of Novel Synthetic Biology Technology in Precisely Regulating Gene Expression and Promoting the Efficiency of Fatty Acid Biosynthesis[J]. Journal of Shanghai Jiaotong University, 2019, 53(1): 1-10.

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