Practice question

RNA-seq platforms sequence DNA, so RNA must be reverse transcribed. Reverse transcriptase, an RNA-dependent DNA polymerase derived from retroviruses such as M-MLV or AMV, synthesizes complementary DNA, cDNA, from RNA template using oligo-dT, random hexamer or gene-specific primers. RNase H or second-strand synthesis then generates double-stranded cDNA suitable for adapter ligation and PCR amplification. RNA polymerase synthesizes RNA from DNA, DNA polymerase requires DNA template, and ligase joins nicks. Only reverse transcriptase possesses RNA to DNA polymerase activity essential for initial conversion.