| − | '''RNA polymerases''', often abbreviated to '''RNAP''', are the enzymes in a cell responsible for [[transcription|synthesizing]] strands of [[RNA]]. Because this function is essential to life, all organisms (and quite a few viruses) contain at least one type of RNA polymerase. Depending on the RNA polymerase, transcription requires either a [[DNA]] or an RNA template; although in most contexts, "RNA polymerase" refers to the DNA-dependant RNA polymerases, which use a DNA template to [[transcription|transcribe]] genes into [[mRNA]] ("messenger" RNA). [[reverse transcriptase|Reverse transcriptases]] are enzymes (usually associated with [[retrovirus|retroviruses]]) that perform the opposite function, using an RNA template to synthesize a [[DNA]] product. | + | '''RNA polymerases''', often abbreviated to '''RNAP''', are the enzymes in a cell responsible for [[transcription|synthesizing]] strands of [[RNA]]. Because this function is essential to life, all organisms (and quite a few viruses) contain at least one type of RNA polymerase. Depending on the RNA polymerase, transcription requires either a [[DNA]] or an RNA template; although in most contexts, "RNA polymerase" refers to the DNA-dependant RNA polymerases which use a DNA template to [[transcription|transcribe]] genes into [[mRNA]] ("messenger" RNA). [[reverse transcriptase|Reverse transcriptases]] are enzymes (usually associated with [[retrovirus|retroviruses]]) that perform the opposite function, using an RNA template to synthesize a [[DNA]] product. |