<P> RNA polymerase ( ribonucleic acid polymerase ) , both abbreviated RNAP or RNApol , official name DNA - directed RNA polymerase , is a member of a family of enzymes that are essential to life : they are found in all organisms ( - species ) and many viruses . RNAP locally opens the double - stranded DNA ( usually about four turns of the double helix ) so that one strand of the exposed nucleotides can be used as a template for the synthesis of RNA , a process called transcription . A transcription factor and its associated transcription mediator complex must be attached to a DNA binding site called a promoter region before RNAP can initiate the DNA unwinding at that position . RNAP has intrinsic helicase activity , therefore no separate enzyme is needed to unwind the DNA ( in contrast to DNA polymerase ) . RNAP not only initiates RNA transcription , it also guides the nucleotides into position , facilitates attachment and elongation , has intrinsic proofreading and replacement capabilities , and termination recognition capability . In eukaryotes , RNAP can build chains as long as 2.4 million nucleotides . </P>
<P> RNA polymerase ( ribonucleic acid polymerase ) , both abbreviated RNAP or RNApol , official name DNA - directed RNA polymerase , is a member of a family of enzymes that are essential to life : they are found in all organisms ( - species ) and many viruses . RNAP locally opens the double - stranded DNA ( usually about four turns of the double helix ) so that one strand of the exposed nucleotides can be used as a template for the synthesis of RNA , a process called transcription . A transcription factor and its associated transcription mediator complex must be attached to a DNA binding site called a promoter region before RNAP can initiate the DNA unwinding at that position . RNAP has intrinsic helicase activity , therefore no separate enzyme is needed to unwind the DNA ( in contrast to DNA polymerase ) . RNAP not only initiates RNA transcription , it also guides the nucleotides into position , facilitates attachment and elongation , has intrinsic proofreading and replacement capabilities , and termination recognition capability . In eukaryotes , RNAP can build chains as long as 2.4 million nucleotides . </P>
what role does rna polymerase play in transcription
what role does rna polymerase play in transcription
locally opens the double - stranded DNA ( usually about four turns of the double helix ) so that one strand of the exposed nucleotides can be used as a template for the synthesis of RNA , a process called transcription
locally opens the double - stranded DNA ( usually about four turns of the double helix ) so that one strand of the exposed nucleotides can be used as a template for the synthesis of RNA , a process called transcription