Question: how rna is edited prior to leaving the nucleus

title: Post-transcriptional modification
text: Regulatory sequence Regulatory sequence Enhancer / silencer Promoter 5'UTR Open reading frame 3'UTR Enhancer / silencer Proximal Core Start Stop Terminator Transcription DNA Exon Exon Exon Intron Intron Post-transcriptional modification Pre - mRNA Protein coding region 5'cap Poly - A tail Translation Mature mRNA Protein The structure of a eukaryotic protein - coding gene . Regulatory sequence controls when and where expression occurs for the protein coding region ( red ) . Promoter and enhancer regions ( yellow ) regulate the transcription of the gene into a pre-mRNA which is modified to remove introns ( light grey ) and add a 5 ' cap and poly - A tail ( dark grey ) . The mRNA 5 ' and 3 ' untranslated regions ( blue ) regulate translation into the final protein product .