1. Chapter 17 Transcription and Translation From Gene to Protein

2. Overview The “recipe” for a protein is encoded within the DNA One gene, one protein Recipe for one protein is copied into a working version in the form of RNA (Transcription) Recipe in RNA is used to make a protein (Translation)

3. Two Steps Required for Gene Expression Transcription Polymerization of RNA molecule from DNA template strand One gene one transcript Translation Production of a protein molecule based on the instructions contained within a mRNA molecule

4. Transcription Components Promotor TATA box RNA Polymerase RNA nucleotides Termination sequence

5. Steps in Transcription Initiation Elongation Termination

6. Transcription Initiation Transcription factors bind to TATA box RNA Polymerase joins transcription factors DNA strands opened RNA nucleotides aligned

7. Transcription Elongation Initiation factors remain at promotor RNA Polymerase catalyzes building of RNA molecule 5’-3’ direction of formation of RNA Continues until termination signal is reached

8. Transcription Termination RNA Polymerase reaches the termination signal Snap back Rho Complex destabilization Release of all components DNA closes

9. Movies of Transcription Transcription

10. Post Transcriptional Modification Eukaryotes only 3’ end- poly A tail 5’ end methylated guanine cap Exons Introns Splicing Splicosome Mature mRNA

11. Post transcriptional Modifications Splicing

12. Types of RNA r RNA - Pol I m RNA – Pol II t RNA – Pol III

13. Translation Manufacture of protein from information in mRNA

14. Components Involved in Translation Messenger RNA Ribosome A slot P slot E slot Transfer RNA Amino acids

15. Terms Codon Anticodon Gene Chromosome Genome

17. Steps found in Translation Initiation Elongation Termination

18. Initiation of Translation 5’ end of mRNA Start codon AUG Small sub unit of the ribosome Initiation tRNA Methionine Large sub unit of ribosome A slot P slot E slot

19. Elongation of Translation New A.A. bearing tRNA enters the A slot A.A. transferred from P slot onto AA in A slot Ribosome slides over one codon Continues until a stop codon enters the A slot

20. Termination of Translation Stop codon enters the A slot No tRNA H bonds to stop codon Release factor enters A slot Peptide chain hydrolysed from the tRNA in the P slot

21. Movie of Translation Translation Musical version

22. Recap