HP1γ介导靶向常染色质的基因传递系统的研究

It has become a major obstacle in the development of non-viral gene carriers to improve their transfection efficiency to a comparable level with viral gene carriers. Based on the primary carriers, Gua-SS-PAAs (guanidinylated Poly (amido amine) s with multiple disulfide linkages) which have been constructed by applicant, functionalized gene delivery systems are designed according to the euchromatin targeting and enhanced transcription elongation mediated by HP1γ (Heterochromatin protein 1γ). TMEM16A-EGFP-N1 is selected as a model drug. HP1γ/Gua-SS-PAAs/pDNA gene delivery systems are constructed by the self-assembly between Gua-SS-PAAs and HP1γ/DNA complexes formed through the specific recognition of the gene coding sequence of pDNA by HP1γ. A variety of experimental techniques will be used to study the physical and chemical properties, biological indicators, and transport mechanisms of HP1γ/Gua-SS-PAAs/pDNA. Structural factors affecting the transfection efficiency of gene delivery systems throughout the transcription and translation process will be investigated. The critical role of HP1γ in euchromatin targeting and gene expression promoting effect will be revealed in the course of this study. New ideas will be introduced to the development of efficient gene delivery systems.

针对目前非病毒类基因载体面临的转染效率显著低于病毒类载体这一主要问题，以申请者早期构建的Gua-SS-PAAs（胍基化的含二硫键的聚氨基胺类聚合物）作为基础载体，利用HP1γ (Heterochromatin protein 1γ)介导的常染色质靶向作用及促转录延伸作用，拟构建一种转染效率更高的功能化基因传递系统。选取已构建的TMEM16A-EGFP-N1质粒作为模型药物，将HP1γ通过特异性识别质粒DNA编码序列所形成的复合物，利用Gua-SS-PAAs包载，制备HP1γ/Gua-SS-PAAs/pDNA基因传递系统。利用多种方法对拟构建传递系统的理化性质、生物学性能及转运机制进行研究，分析基因传递系统在转录和翻译过程中影响自身转染效率的结构因素，揭示HP1γ在常染色质靶向及促进基因表达过程中的关键作用。为优化设计更高效的基因治疗药物传递系统提供新的思路。

针对目前非病毒类基因载体面临的转染效率显著低于病毒类载体这一主要问题，以申请者早期构建的Gua-SS-PAAs（胍基化的含二硫键的聚氨基胺类聚合物）作为基础载体，利用HP1γ (Heterochromatin protein 1γ)介导的常染色质靶向作用及促转录延伸作用，构建了一种转染效率更高的功能化基因传递系统。选取已构建的TMEM16A-EGFP-N1等质粒作为模型药物，将HP1γ通过特异性识别质粒DNA编码序列所形成的复合物，利用Gua-SS-PAAs包载，制备HP1γ/Gua-SS-PAAs/pDNA基因传递系统。. 利用多种方法对构建的上述传递系统的理化性质、生物学性能及转运机制进行研究，分析基因传递系统在转录和翻译过程中影响自身转染效率的结构因素，验证并揭示HP1γ在常染色质靶向及促进基因表达过程中的关键作用。. 截至目前，课题组采用合理的制剂制备和评价方法，成功构建HP1γ/Gua-SS-PAAs/pDNA基因传递系统。建立科学合理的常染色质靶向效率评价体系；明确了拟构建的不同基因传递系统常染色质靶向效率和其转染效率之间的关系；并且在转录水平和翻译水平明确影响拟构建基因传递系统转染效率的结构因素，为优化设计更高效的基因治疗药物传递系统提供新的思路。本项目已撰写并发表研究论文2篇，分别发表在ASIA J Pharm Sci（IF 4.560）、及山东医药2个学术期刊上。申请国家发明专利2项。此外，另有4篇论文已撰写完成，目前处于审稿阶段，总IF大于16。