The Template Constructions And Biological Applications Of DNA Nanostructures

Traditional gene mapping is accomplished with the self-association of complementary single strand probes labeled luciferin.The results are observed and recorded under a fluorescence microscope.The background signal of fluorescence spectrum obtained by this method is complex,low quality and not intuitive.In addition,fluorescence spectrum can only be used to distinguish sequences greater than 300 bp due to the influence of optical diffraction limit.Widespread applications of atomic force microscopy(AFM)which provides a mechanical imaging new method with nanoscale resolution for gene analysis are hampered by the lack of specific shapes of the labels.Therefore,the design and construction of three-dimensions complex DNA nanostructures and gene mapping using the DNA nanostructures is the main research content of this paper.We first design and construct a one-dimensional DNA tiles nanostructure(RDN)which assembled with Fe₃O₄ nano-magnetic particles to form an array of nano-magnetic particles.Further,we design and construct a three-dimensional ring origami structure,which successfully template and self-assemble liposome.Finally,we design and construct a variety of two-dimensional nanostructured DNA origami probes,which can be used for high-precision multi-sites gene localization of the genome DNA sequence of Phi X 174 phage.We obtain a high-precision imaging with a resolution less than 11 nm,and four different gene positions are successfully located through AFM mechanized imaging.In this paper,we demonstrate DNA nanostructures can be used for multi-dimensional template assembly of magnetic nanoparticles and biomacromolecules.We innovatively use the DNA exoskeleton template to self-assemble nanoscale liposomes.A variety of DNA origami probes are constructed,which greatly enriched the diversity of identifiable probes.Atomic force microscopy(AFM)is used to successfully locate four different gene loci in genomic DNA sequences,which overcomes the shortcomings of traditional optical mapping of genomes in gene detection,such as complex background signals,low quality and non-intuitive.