1. From DNA to Protein

2. DNA Review Nucleic acid Double helix Two strands of nucleotides Phosphate-sugar backbone Nitrogenous base steps Adenine Guanine Cytosine Thymine

3. Ribonucleic acid (RNA) Nucleic acid Usually single strand of nucleotides Sugar-phosphate backbone Nitrogenous bases Adenine Guanine Cytosine Uracil

4. DNA/RNA Comparison Structure DNA: double helix RNA: single strand Sugars DNA: deoxyribose RNA: ribose Bases DNA: A, G, C and T RNA: A, G, C, and U Base-pairing rules DNA A = T G = C RNA A = U G = C

5. Getting the info out… Where is DNA stored?

6. Getting the info out… Where is DNA stored? nucleus Where are proteins synthesized?

7. Getting the info out… Where is DNA stored? nucleus Where are proteins synthesized? Ribosomes in the cytoplasm Problem?

8. Getting the info out… Where is DNA stored? nucleus Where are proteins synthesized? Ribosomes in the cytoplasm Problem? How does the cell get the info to the workers?

9. RNA is the solution! 3 types of RNA mRNA: messenger RNA tRNA: transfer RNA rRNA: ribosomal RNA RNA helps build proteins

10. mRNA Single, uncoiled chain Carries genetic information from nucleus to cytoplasm

11. tRNA Single chain folded into a hairpin ~80 nucleotides long Binds to specific amino acids ~ 45 varieties of tRNA

12. rRNA RNA folded into globular form Combines with proteins to form ribosomes Ribosomes build proteins!

13. Transcription of RNA Copying genetic info from DNA into RNA Begins at promoter (special DNA segment) Ends at termination signal Assisted by RNA polymerase

14. RNA DNA RNA polymerase Transcription Base pairing DNA RNA G ≡ C C ≡ G T = A A = U Adenine (DNA and RNA) Cystosine (DNA and RNA) Guanine(DNA and RNA) Thymine (DNA only) Uracil (RNA only)

15. Importance of Proteins Proteins determine structure & function of cell Protein = polymer of amino acids Folded upon itself (globular) 3-D structure IMPORTANT for function

16. Genetic Code Genetic code = triplets of mRNA that code for amino acids CODON = 3 nucleotide bases in row ONLY 20 different amino acids 64 possible triplets START codon: AUG STOP codons: UAA, UAG, UGA

17. Genetic Code

18. Translation RNA  protein Process of assembling polypeptides from mRNA info

19. Protein synthesis 1. mRNA is transcribed in nucleus and leaves through nuclear pore

20. Protein synthesis 2. mRNA attaches to a ribosome translation starts at start codon (AUG) tRNA has anticodon - complementary to mRNA codon

21. Protein synthesis 3. Polypeptide assembly line

22. Insert video from Presentation – Protein synthesis

23. Protein Synthesis

24. nucleus mRNA tRNA ribosomeanticodon mRNAcodon