ARTIFICIAL BASE PAIR CAPABLE OF FORMING SPECIFIC BASE PAIR
申请人:Hirao Ichiro
公开号:US20120231462A1
公开(公告)日:2012-09-13
The present invention provides a double-stranded nucleic acid in which at least one nucleic acid strand includes an unnatural base that forms a self-complementary base pair or an unnatural base that forms a base pair with any natural base with substantially the same thermal stability. The present invention also provides a method of hybridizing a first nucleic acid strand with a second nucleic acid strand, wherein the first nucleic acid strand includes an unnatural base that forms a self-complementary base pair or an unnatural base that forms a base pair with any natural base with substantially the same thermal stability, and a method of applying the nucleic acid to SNP detection, a DNA chip, DNA/RNA computing, or an in vitro translation system. The present invention provides a method of introducing an unnatural base into a nucleic acid strand and thereby controlling the thermodynamic stability in hybridization of the nucleic acid strand.
Fluorescent nucleobase analogues are useful in a wide variety of biology and biotechnology tools as molecular probes and reporters for nucleic acids. Here we present a novel fluorescent purine analogue, 7-(2,2'-bithien-5-yl)-imidazo[4,5-b]pyridine (denoted as Dss). The nucleoside triphosphates of Dss can be site-specifically incorporated into DNA and RNA by polymerases, opposite its pairing partner, pyrrole-2-carbaldehyde (Pa), in DNA templates. Despite its high specificity in replication and transcription, Dss in oligonucleotides functions as a universal base that pairs with all four natural bases with nearly equal thermal stabilities. Thus, Dss would be a powerful tool for fluorescent base replacements at specific positions in functional DNA and RNA molecules.