Polyassembly formation of complementary half-sliding oligo-DNAs and atomic force microscopic observation.

Oligonucleotides, especially oligo-DNAs, are useful building blocks for construction nanometer scale ordered architectures. Many researchers have been carried out to construct nano-architectures using complementary hydrogen bonding of DNAs. However, in order to achieve rational and robust design of various functional nano-architectures using DNAs, it is extremely important to establish basic principles of assembly patterns of oligo-DNAs based on their complementarity. In this study, to obtain basic information of polyassembly for simple oligo-DNA systems, formation of multiple assemblies of complementary half-sliding oligo-DNAs (cHSOs) was investigated with varying the length and sequence (GC content). A pairs of cHSOs were mixed in combination of complementary each other, and then the formation of high-molecular-weight polyassembly was evaluated by polyacrylamide gel electrophoresis (PAGE) and size exclusion chromatography (SEC). Moreover, the morphology and shape of the polyassembly was investigated by atomic force microscope (AFM) observation on mica. The obtained polyassembly displayed linear and networked morphology, and the continuous length and patterns of the assembly was depend on the length, GC contents and the concentration of the cHSOs.

Construction of supramolecular assemblies and self-organized structures using oligo-DNAs.

To obtain fundamental theories for construction of self-organized structures using oligonucleotides, we constructed multiple aggregates with half-sliding oligo-DNAs. We used several types of half-sliding oligo-DNAs with different stability and number of residues. The formation of multiple aggregates by the oligo-DNAs was confirmed by size exclusion chromatography (SEC). The shape of the aggregates was investigated by atomic force microscope (AFM), and linear structures of multiple aggregates of half-sliding oligo-DNAs were observed.