苏云金芽胞杆菌DeoR调控芽胞形成的分子机制

苏云金芽胞杆菌（Bt）是广泛使用的一种生防制剂，主要成分为杀虫晶体蛋白（Cry）和芽胞。许多Cry蛋白的表达依赖于芽胞形成，芽胞形成调控与Cry蛋白表达密切相关。关于Bt表达与调控的研究主要集中于cry基因，而对芽胞形成调控研究较少，芽胞形成调控机制仍待深入。前期发现一个转录活性很高、功能未知的deoR基因，可以显著影响Bt芽胞形成。在此基础上，本项目拟以Bt HD73菌株为研究对象，利用基因敲除、功能互补、基因过表达、点突变等功能基因组学、生化检测等方法，同时结合CHIP-seq及转录组学，明确DeoR的功能，揭示DeoR调控芽胞形成的分子机制。本项目预期结果不仅有利于解析Bt芽胞形成的分子调控机制，而且为Bt工程菌株改造和工业化生产奠定基础，进一步为Bt的田间应用提供科学依据。

Bacillus thuringiensis(Bt) is a kind of widely-used biocontrol agent with the main components of the mixture of insecticidal crystal proteins(Cry) and spores. Many Cry protein expression is closely connected to sporulation regulation since that the Cry proteins are expressed by a sporulation-dependent manner. However, the studies on genes expression and regulation in Bt strain mostly focused on those encoding Cry proteins, rather than the sporulation regulation. Thus, the regulatory mechanisms of sporulation in Bt still need to be further explored and verified. Our previous study revealed that a deoR gene with unknown function retained a very high transcriptional activity in a Bt strain based on the transcriptomics analysis, and deoR significantly affected sporulation. Based on these results, this project aims to reveal the function of DeoR and the molecular mechanisms of sporulation regulated by DeoR in Bt by combining functional genomics techniques, such as gene knockout, complementation, overexpression, site-directed mutagenesis and CHIP seq, transcriptomics analysis. Our finding will not only help reveal the molecular mechanisms of sporulation in Bt, but also lay the foundation for engineered Bt strains construction and industrial production, and further provide theoretical support for Bt application in the field.