Efficient Gene Repair System Basedon DNA Origami Scaffolds

DNA in the human body is affected by the external environment,such as environmental factors and the effects of ultraviolet radiation,as well as the erosion of internal carcinogens,and its internal genetic molecules are also unstable.Every day tens of thousands of natural changes occur.Gene mismatches may occur when genes are replicated and the genetic material of humans is relatively stable because enzymes in the human body that can be monitored and repaired function.Gene repair refers to the repair of defective genes in situ and the correction of pathogenic genes in target cells to ensure the stability of genetic material in the human body and safeguard the normal human life and health.Gene damage refers to the gene in the replication process due to base deletion or mismatch and other causes of gene nucleotide sequence changes,leading to changes in genetic characteristics.Research shows that many cancer and gene damage have a great relationship.DNA is anattractive polymer construction material for nanodeyices and nanostructures because of its ability to self-identify and self-assembleThe formation of the assembly relies on a fundamental,specific interaction to create a series of nanoscale structures that are well-rigid,shape-controllable and precisely positioned by specific design and self-assembly.Most DNA-based higher order structures,such as DNA cages,2D and 3D DNA crystals or DNA origami structures,are based on complementarily-stable DNA duplex structures.There may be many non-canonical patterns of pairing between and within the DNA strands that lead to the formation of unusual structures including but not limited to G-quadruplexes,i-motifs,triplexes,and parallel strand duplexes.These structures create more diverse DNA-based building blocks and have some advantages over traditional double-stranded DNA.DNA repair system is an important system of human defense against mutations caused by various factors,DNA damage and eventually deterioration.Among them,human 8-oxoguanine DNA glycosidase(hOGG1)is involved in the excision and repair of DNA oxidative bases and has the ability to specifically recognize and excise 8-oxoG in the genome and prevent the transversion of G:C to T:A after excision Generate ap site,ap site by APE 1 enzyme excision,play an important role in preventing cell malignant transformation.In this research,based on the DNA nanostructures,the structure and orientation of the scaffolds were precisely designed.The HOGG1 and APE1 enzymes were linked to the scaffolds.The scaffold-enzyme gene repair system.The realtime fluorescence quantitative PCR is used to detect the enzyme activity.By designing the scaffold structure,the immobilized enzyme can be used to precisely control the distance between the enzymes,thereby increasing the enzyme activity and enhancing the efficiency of gene repair.The method of combining DNA nanostructures with enzymes established in this research has resulted in an increase in the efficiency of gene repair.Due to the good biocompatibility of DNA nanostructure,the application of the detection method in actual cell samples will be realized in the future,which is very helpful to the repair of damaged cells in vivo and the prevention of cancer.