Nucleic acids labeled with naphthoquinone probe

摘要

A sequence directed reagent is constructed by conjugating a methyl naphthoquinone derivative to a hexamethylamino linker attached to the 5' terminus of an oligonucleotide. Annealing this modified fragment of DNA to its complementary sequence allows for target modification subsequent to photochemical activation. The product of this reaction is a covalent crosslink between the reagent and target strands resulting from an alkylation of DNA by the photoexcited quinone. The modified sequence is not labile to acid, base or reductants, and blocks the exonuclease activity of the Klenow fragment of DNA polymerase I. In another embodiment, a highly reactive moiety, such as Br is attached to the methyl group of the naphthoquinone derivative. This reagent is similarly linked to an oligonucleotide probe. Activation of this probe linked alkylating agent is by a reductive signal which may either naturally occur within the cell, such as an enzyme, or introduced into the media containing the target molecule.