Abstract: A stable complex, we refer to as a PD-Loop, between double stranded nucleic acid and a nucleobase polymer is assembled with the aid of strand invading peptide nucleic acid (PNA). The PD-Loop can be used in the detection, analysis, quantitation and even in the affinity capture of the duplex nucleic acid. Alternatively, the PD-Loop can be used to initiate polymerase extension of a primer to thereby facilitate sequencing of the double stranded nucleic acid even in the presence of large excesses of unrelated double stranded nucleic acid. As an additional feature, the PD-Loop can also be used to generate a construct comprised of a double stranded nucleic acid through which is threaded a single stranded dosed circular nucleic acid wherein the closed circular nucleic acid can be used in a signal amplification methodology.

Abstract: A stable complex, we refer to as a PD-Loop, between double stranded nucleic acid and a nucleobase polymer is assembled with the aid of strand invading peptide nucleic acid (PNA). The PD-Loop can be used in the detection, analysis, quantitation and even in the affinity capture of the duplex nucleic acid. Alternatively, the PD-Loop can be used to initiate polymerase extension of a primer to thereby facilitate sequencing of the double stranded nucleic acid even in the presence of large excesses of unrelated double stranded nucleic acid. As an additional feature, the PD-Loop can also be used to generate a construct comprised of a double stranded nucleic acid through which is threaded a single stranded dosed circular nucleic acid wherein the closed circular nucleic acid can be used in a signal amplification methodology.

Abstract: A stable complex, we refer to as a PD-Loop, between double stranded nucleic acid and a nucleobase polymer is assembled with the aid of strand invading peptide nucleic acid (PNA). The PD-Loop can be used in the detection, analysis, quantitation and even in the affinity capture of the duplex nucleic acid. Alternatively, the PD-Loop can be used to initiate polymerase extension of a primer to thereby facilitate sequencing of the double stranded nucleic acid even in the presence of large excesses of unrelated double stranded nucleic acid. As an additional feature, the PD-Loop can also be used to generate a construct comprised of a double stranded nucleic acid through which is threaded a single stranded closed circular nucleic acid wherein the closed circular nucleic acid can be used in a signal amplification methodology.

Abstract: The invention relates to nucleic acid clamps and methods for using nucleic acid clamps, for example, to inhibit gene expression or cleavage, or to specifically cleave a target nucleic acid. Nucleic acid clamps are molecular devices which can bind nucleic acids with affinity and specificity and have a recognition sequence as small as seven bases. Nucleic acid clamps can be used to modify the effective recognition sequence of restriction endonucleases, reducing the frequency and enhancing the length of the recognition sequence, but without diminishing specificity. The invention also relates to methods for the use of nucleic acid clamps for the treatment of disorders involving abnormal gene expression.