1. Gene Expression: from DNA to protein
How is DNA transcribed to RNA?
In bacteria
In eukaryotic cells
How is mRNA translated to protein?

2. Central dogma
phenotype

3. Transcription of RNA from DNA
promoter 5’ 3’

4. Ribosomes act as the workbench for translation
E. coli ribosome; large subunit in pink; small subunit in blue

5. tRNAs match amino acids to mRNA codons

6. Aminoacyl tRNA synthetases “charge” amino acids to the right tRNAs

7. The universal genetic code

8. Translation starts at first AUG from 5’ end

9. Translation termination
No tRNAs recognize stop codons. The ribosome stalls, and a release factor terminates translation.

10. mRNA is translated to protein
Initiation: ribosomes bind to 5’ end of messenger RNA (mRNA), along with initiator Met-tRNA
Elongation: proceeds 5'  3' along mRNA, in 3-base increments (codons)
Polypeptide grows from N-terminus to C- terminus
Termination: at stop (nonsense) codon

11. Prokaryotic gene expression

12. Eukaryotic gene expression

13. Pre-mRNA processing in eukaryotes: addition of 5’ cap

14. Pre-mRNA processing in eukaryotes: splicing to remove introns

15. Pre-mRNA processing in eukaryotes: polyadenylation at 3’ end

16. Animations of transcription and translation
Bioflix
Molecular visualization on YouTube: