mRNA Processing and Splicing

Front

5’ cap

Back

modified guanine

Front

3’ poly-A tail

Back

50-250 A's

Front

Functions of 5’ cap and 3’ tail

Back

Export, protect mRNA, attach to ribosomes

Front

Poly A polymerase

Back

adds long chain of adenine

Front

Longer poly-A tail

Back

increases stability

Front

Pre-mRNA

Back

contains introns and exons

Front

Introns

Back

noncoding sequences

Front

Exons

Back

code for amino acids

Front

Splicing

Back

introns cut out, exons joined

Front

snRNPs

Back

small nuclear ribonucleoproteins