Natural or unnatural single-stranded nucleic acids can bind to the complementary nucleic acid strand(s) with sequence specificity to form duplex or triplex structure. Such property could play a crucial rule for developing various bio-products through successful application of gene-related bio technologies.
Natural nucleic acids (DNA and RNA), however, are well known to have not so high binding ability and decompose rapidly by nucleases, concluding less usefulness as a molecular tool for biotechnologies. Numbers of artificial nucleic acids have been developed for excellent tool of the biotechnologies. In 1997, we created the first generated BNA, 2’-O,4’-C-methylene-bridged nucleic acid(2’,4’-BNA) as a novel nucleic acid analog, a potential molecular tool for biotechnologies, on a basis of conformational features of natural nucleic acids. 2’,4’-BNA-oligos (oligonucleotides modified with one to several unit(s) of 2’,4’-BNA monomer) exhibit extremely high binding abilities against not only single-stranded RNA, DNA complements but also double-stranded DNAs, along with a moderate nuclease resistant property. Now a day, 2’,4’-BNA is widely used for various practical applications, such as for therapeutics, diagnostics, researching reagents, as the name “LNA.”
Following innovation of 2’,4’-BNA (LNA), we have been continuously producing new generations’ bridged nucleic acid: 2’,4’-BNACOC , 3’-, and 5’-amino-2’,4’-BNA (the second generation) gain higher nuclease resistant ability with remaining strong binding abilities, and 2’,4’-BNANC(the third generation) is shown to be most potential from the viewpoints of both binding and nuclease resistant abilities. These BNA, possessing desired profiles for application to bio technologies, should be “key materials” to make various kinds of valuable gene-related bio-products.