reversetranscribe

Reverse transcription is the process by which RNA is used as a template to synthesize complementary DNA (cDNA). The enzyme reverse transcriptase catalyzes this reaction and is found in retroviruses, retrotransposons, and in some cellular systems such as telomerase. In molecular biology, the ability to reverse transcribe RNA enables researchers to convert RNA into DNA for subsequent analysis. The verb form is to reverse transcribe.

Reverse transcriptase is an RNA-dependent DNA polymerase that often includes RNase H activity, which degrades the RNA strand of an RNA-DNA hybrid. Many laboratory enzymes are derived from retroviral reverse transcriptases and engineered for higher thermostability and fidelity. In standard workflows, first-strand cDNA is synthesized from an RNA template using primers like oligo-dT, random hexamers, or gene-specific primers. A second-strand synthesis step may follow to produce double-stranded cDNA.

The cDNA generated by reverse transcription serves as a template for PCR, quantitative PCR (RT-qPCR), cloning, and sequencing. These methods underpin studies of gene expression, transcript discovery, and RNA sequencing.

Historically, the discovery of reverse transcriptase by Temin and Baltimore in 1970 revealed how RNA viruses replicate and enabled the creation of cDNA libraries. This work transformed virology and molecular biology and led to numerous diagnostic and research tools.