GENE
Exon 1
Intron
Exon 3
Intron
Exon 4
Exon 2
Intron
Promoter
Enhancer
mRNA transcript
Exon 1
Intron
Exon 3
Intron
Exon 4
Exon 2
Intron
5・-untranslated
region
5・
3・
Poly(A) signal
Exon 1
Exon 3
Exon 4
Exon 2
3・
3・-untranslated
region
(AAAAAA)n
Mataure mRNA
Transcription
Processing
7-mG cap
The Organization of an Eukaryotic Gene