Abstract: The present invention entails methods and kits for carrying them out based on the discovery that an RNA replicase, such as Q&bgr; replicase, has DNA-dependent RNA polymerase (“DDRP”) activity with nucleic acid segments, including DNA segments and DNA:RNA chimeric segments, which comprise a 2′-deoxyribonucleotide or an analog thereof and which have sequences of RNAs that are autocatalytically replicatable by the replicase.

Abstract: The present invention entails methods, and kits for carrying them out, based on the discovery that an RNA replicase, such as Q&bgr; replicase, has DNA-dependent RNA polymerase (“DDRP”) activity with nucleic acid segments, including DNA segments and DNA:RNA chimeric segments, which comprise a 2′-deoxyribonucleotide or an analog thereof and which have sequences of RNAs that are autocatalytically replicatable by the replicase. The discovery of this DDRP activity provides methods of the invention for nucleic acid amplification wherein a nucleic acid, with a DNA segment with the sequence of an RNA that is autocatalytically replicatable by an RNA replicase, is provided as a substrate for the replicase. The replicase catalyzes synthesis, from the DNA segment, of the RNA, which the replicase then autocatalytically replicates. The invention entails use of the amplification methods in detecting nucleic acid analytes, as in nucleic acid probe hybridization assays.

Abstract: The present invention entails methods, and kits for carrying them out, based on the discovery that an RNA replicase, such as Q&bgr; replicase, has DNA-dependent RNA polymerase (“DDRP”) activity with nucleic acid segments, including DNA segments and DNA:RNA chimeric segments, which comprise a 2′-deoxyribonucleotide or an analog thereof and which have sequences of RNAs that are autocatalytically replicatable by the replicase. The discovery of this DDRP activity provides methods of the invention for nucleic acid amplification wherein a nucleic acid, with a DNA segment with the sequence of an RNA that is autocatalytically replicatable by an RNA replicase, is provided as a substrate for the replicase. The replicase catalyzes synthesis, from the DNA segment, of the RNA, which the replicase then autocatalytically replicates. The invention entails use of the amplification methods in detecting nucleic acid analytes, as in nucleic acid probe hybridization assays.

Abstract: The present invention provides a novel, single-stranded DNA probe which comprises an anti-target segment, a strand of a promoter, and a reporter segment, arranged so that a target segment, which has a 3'-hydroxyl at its terminus, can prime DNA polymerase-catalyzed extension of the target segment along the probe as template, when the target segment is hybridized to the anti-target segment of the probe, to provide an extension product from which transcripts, with the sequence complementary to that of the reporter segment of the probe, can be made by transcription from the promoter corresponding to the promoter segment of the probe. The transcripts, optionally after further amplification or other processing, can be detected. In one embodiment of the invention, the transcripts will be autocatalytically replicatable by an RNA replicase such as Q.beta. replicase.

Abstract: The present invention entails methods, and kits for carrying them out, based on the discovery that an RNA replicase, such as Q.beta. replicase, has DNA-dependent RNA polymerase ("DDRP") activity with nucleic acid segments, including DNA segments and DNA:RNA chimeric segments, which comprise a 2'-deoxyribonucleotide or an analog thereof and which have sequences of RNAs that are autocatalytically replicatable by the replicase. The discovery of this DDRP activity provides methods of the invention for nucleic acid amplification wherein a nucleic acid, with a DNA segment with the sequence of an RNA that is autocatalytically replicatable by an RNA replicase, is provided as a substrate for the replicase.