TRANSCRIPTION
- Transcription is the process by which the information in a Segment of DNA is copied into messenger RNA (mRNA)
- Transcription is the first step in gene expression.
- It occurs in the nucleus of eukaryotic cells and the cytoplasm of prokaryotic cells.
- The resulting mRNA molecule is used in the next stage, translation, to synthesize proteins.
RNA POLYMERASE
- The enzyme involved in transcription is RNA polymerase. Unlike DNA polymerase it can initiate transcription by itself, it does not require primase.
More exactly it is a DNA dependent RNA polymerase.
- During the process of transcription, RNA polymerase copies the sequence of DNA into an RNA sequence with the help of the enzyme helicase that opens up the wounded DNA strands.
- It differ in prokaryote and eukaryote
RNA POLYMERASE IN PROKARYOTE
