Gene Transcription

Transcription is the first step in gene expression. It involves copying a gene's DNA sequence to make an RNA molecule. • Transcription is performed by enzymes called RNA polymerases, which link nucleotides to form an RNA strand (using a DNA strand as a template). • Transcription has three stages: initiation, elongation, and termination. • In eukaryotes, RNA molecules must be processed after transcription: they are spliced and have a 5' cap and poly-A tail put on their ends. • Transcription is controlled separately for each gene in your genome.