Abstract: Methods for making cDNA molecules, for amplification of RNA by PCR and for preparation of cDNA libraries are provided. Kits for making cDNA molecules also are provided. Compositions are also provided comprising mixtures of reagents, including reverse transcriptases, buffers, cofactors and other components, suitable for immediate use in conversion of RNA into cDNA and RT PCR without dilution or addition of further components. These compositions are useful, alone or in the form of kits, for cDNA synthesis or nucleic acid amplification (e.g., by the Polymerase Chain Reaction) or for any procedure utilizing reverse transcriptases in a variety of research, medical, diagnostic, forensic and agricultural applications.

Abstract: Improved methods of studying RNA molecules are provided. In particular, methods of treating mixtures of RNA molecules so as to enrich the mixture for a desired type of RNA molecule are provided. For example, the methods permit depletion of mRNA from complex mixtures to facilitate study of microRNAs in the mixture.

Abstract: Methods for making cDNA molecules, for amplification of RNA by PCR and for preparation of cDNA libraries are provided. Kits for making cDNA molecules also are provided. Compositions are also provided comprising mixtures of reagents, including reverse transcriptases, buffers, cofactors and other components, suitable for immediate use in conversion of RNA into cDNA and RT PCR without dilution or addition of further components. These compositions are useful, alone or in the form of kits, for cDNA synthesis or nucleic acid amplification (e.g., by the Polymerase Chain Reaction) or for any procedure utilizing reverse transcriptases in a variety of research, medical, diagnostic, forensic and agricultural applications.

Abstract: Compositions and methods are provided that improve the specificity and efficiency of nucleic acid amplification. A binding partner may be bound to a DNA polymerase enzyme where the binding partner substantially inhibits the activity of the polymerase. A second enzyme modifies the binding partner in a manner that relieves the inhibition of the polymerase activity. The activity of the second enzyme may be inhibited in a temperature-sensitive manner such that the second enzyme is active only at elevated temperatures. As a consequence, the polymerase enzyme also is active only when the temperature is elevated.