2. Student Assessment of Learning Gains (SALG) website

4. DNA molecule Gene 1 Gene 2 Gene 3 DNA template strand TRANSCRIPTION TRANSLATION mRNA Protein Codon Amino acid

5. DNA Signal Gene NUCLEUS Chromatin modification Chromatin Gene available for transcription Exon Intron Tail RNA Cap RNA processing Primary transcript mRNA in nucleus Transport to cytoplasm CYTOPLASM Transcription Gene Expression

6. mRNA in cytoplasm Translation CYTOPLASM Degradation of mRNA Protein processing Polypeptide Active protein Cellular function Transport to cellular destination Degradation of protein

7. Transcription

8. 33 1 2 3 Promoter TATA box DNA strand 55 33 55 Transcription factors 55 55 33 33 RNA polymerase 55 55 55 33 33 RNA transcript Transcription initiation complex INITIATION

9. Promoter Transcription unit DNA Start point RNA polymerase 55 55 33 33

10. Promoter Transcription unit DNA Start point RNA polymerase 55 55 33 33 Initiation 33 33 1 RNA transcript 55 55 Unwound DNA Template strand of DNA

11. Promoter Transcription unit DNA Start point RNA polymerase 55 55 33 33 Initiation 33 33 1 RNA transcript 55 55 Unwound DNA Template strand of DNA 2 Elongation Rewound DNA 55 55 55 33 33 33 RNA transcript

12. Promoter Transcription unit DNA Start point RNA polymerase 55 55 33 33 Initiation 33 33 1 RNA transcript 55 55 Unwound DNA Template strand of DNA 2 Elongation Rewound DNA 55 55 55 33 33 33 RNA transcript 3 Termination 55 55 55 33 33 33 Completed RNA transcript

13. Elongation RNA polymerase Nontemplate strand of DNA RNA nucleotides 3  end Direction of transcription (“downstream”) Template strand of DNA Newly made RNA 33 55 55

14. Protein-coding segment Polyadenylation signal 33 3  UTR5  UTR 55 5  Cap Start codon Stop codon Poly-A tail G PPPAAUAAA AAA … NEXT: Add the Poly-AAAAAA tail and GTP Cap (UTR = untranslated region)

15. hn-RNA mRNA Coding segment Introns cut out and exons spliced together 5  Cap Exon1 Intron 55 1 30 40100 Exon2 Intron 120 Exon3 146 33 Poly-A tail 5  Cap 5  UTR3  UTR 1 146 NEXT: (Eukaryotes) Remove Introns Also Alternative Splicing & Trans-splicing occurs SPLICING

16. RNA transcript (pre-mRNA) Exon 1Exon 2Intron Protein snRNA snRNPs Other proteins 55

17. RNA transcript (pre-mRNA) Exon 1Exon 2Intron Protein snRNA snRNPs Other proteins 55 55 Spliceosome

18. RNA transcript (pre-mRNA) Exon 1Exon 2Intron Protein snRNA snRNPs Other proteins 55 55 Spliceosome components Cut-out Intron (lariat) mRNA Exon 1 Exon 2 55

21. The RNA Tie Club was right!

22. RNA transcript (pre-mRNA) Exon 1Exon 2Intron Protein snRNA snRNPs Other proteins 55 55 Spliceosome snRNA ->

23. Amino acid attachment site (a) Two-dimensional structure Hydrogen bonds Anticodon 33 55 tRNA ->

25. Ribosome mRNA Signal peptide Signal- recognition particle (SRP) CYTOSOL Translocation complex SRP receptor protein ER LUMEN Signal peptide removed ER membrane Protein Insulin! SRP-RNA rRNA in ribosomes

26. GFP = Green Florescent Protein (from Jelly fish)

27. Enhancer TATA box Promoter Activators DNA Gene Distal control element Studying Promoters GFP

28. Enhancer TATA box Promoter Activators DNA Gene Distal control element Group of mediator proteins DNA-bending protein General transcription factors Studying Promoters GFP

29. Enhancer TATA box Promoter Activators DNA Gene Distal control element Group of mediator proteins DNA-bending protein General transcription factors RNA polymerase II RNA polymerase II Transcription initiation complex RNA synthesis GFP Studying Promoters

30. Control elements Enhancer Available activators Albumin gene (b) Lens cell Crystallin gene expressed Available activators LENS CELL NUCLEUS LIVER CELL NUCLEUS Crystallin gene Promoter (a) Liver cell Crystallin gene not expressed Albumin gene expressed Albumin gene not expressed GFP (blue) GFP (red) blue! red!

31. “Brainbow” GFP= Nobel Prize 2008 Martin Chalfie, Roger Tsien and Osamu Shimomura

32. TRANSCRIPTION RNA PROCESSING DNA RNA transcript 33 55 RNA polymerase Poly-A RNA transcript (pre-mRNA) Intron Exon NUCLEUS Aminoacyl-tRNA synthetase AMINO ACID ACTIVATION Amino acid tRNA CYTOPLASM Poly-A Growing polypeptide 33 Activated amino acid mRNA TRANSLATION Cap Ribosomal subunits Cap 55 E P A A Anticodon Ribosome Codon E