Patent ID: 7439035

Claim:
A method of identifying or characterizing a compound that modulates ribonuclease H activity, said method comprising: (a) providing a substrate comprising: a heteroduplex molecule comprising a single-stranded RNA oligonucleotide and a single-stranded DNA oligonucleotide hybridized to said RNA oligonucleotide; a fluorophore attached to one of said RNA or DNA oligonucleotides; and a quencher molecule attached to the other of said RNA or DNA oligonucleotides; wherein said fluorophore and said quencher molecule are located within close proximity of each other in said heteroduplex molecule such that fluorescence emission of said fluorophore in said heteroduplex molecule is reduced as compared to a corresponding fluorescence emission in a corresponding heteroduplex molecule lacking said quencher molecule; (b) contacting a source of enzymatically active ribonuclease H with a test compound and said substrate to form a reaction mixture; (c) measuring a test level of fluorescence emission of said fluorophore; and (d) comparing said test level of fluorescence emission with a control level of fluorescence emission obtained from a corresponding control reaction mixture lacking said test compound; wherein a difference between said test level and said control level is indicative that said test compound modulates ribonuclease H activity.