1. Chapter 12-13 – DNA and How Genes Work

2. What is transforming agent? DNA or protein? Avery, MacLeod and McCarty

4. DNA carries the heritable information Avery, MacLeod and McCarty conclusion 1944

5. Hershey and Chase Martha Cowles Chase Alfred Day Hershey

6. Hershey and Chase Bacteriophage: viruses that infect bacterial cells

7. Hershey and Chase

8. Genetic material in virus was DNA DNA is agent of heredity Hershey and Chase conclusion INDEPENDENT FUNCTIONS OF VIRAL PROTEIN AND NUCLEIC ACID IN GROWTH OF BACTERIOPHAGE* B~ A. D. HERSHEY AND MARTHA CHASE (From the Department of Genetics, Carnegie Institution of Washington, Cold Spring Harbor, Long Island) (Received for publication, April 9, 1952) The work of Doermaml (1948), Doermann and Dissosway (1949), and Anderson and Doermann (1952) has shown that bacteriophages T2, T3, and T4 multiply in the bacterial cell in a non-infective form. The same is true of the phage carried by certain lysogenic bacteria (Lwoff and Gutmann, 1950). Little else is known about the vegetative phase of these viruses. The experiments reported in this paper show that one of the first steps in the growth of T2 is the release from its protein coat of the nucleic acid of the virus particle, after which the bulk of the sulfur-containing protein has no further function.

9. DNA – just what is it?

10. Nucleic Acids Monomers = nucleotides Polymer = DNA, RNA

11. DNA Nucleotide (monomer) 4 bases

12. DNA “double helix”

13. DNA

14. A - T G - C

15. DNA “double helix” A - T G - C

16. Rosalind Franklin (1920-1958) X-ray crystalography

17. Structure of DNA Watson and Crick 1953

18. Watson and Crick (1953)

19. Replication Expression DNA

20. DNA Replication

26. DNA Information stored in order of the bases

27. +/- 1200 copies

28. Central Dogma of Cell Biology DNA (gene) Protein

29. GENETICS: TA TUM AND BEADLE GENETIC CONTROL OF BIOCHEMICAL REACTIONS IN NEUROSPORA: AN "AMINOBENZOICLESS" MUTANT* By E. L. TATUM AND G. W. BEADLE DEPARTMENT OF BIOLOGY, STANFORD UNIVERSITY Communicated April 17, 1942 Para-aminobenzoic acid has recently been recognized as a factor required for the growth of a number of micro6rganisms' and as a member of the vitamin B group.2 One of the number of x-ray induced mutants of Neurospora crassa, obtained as described elsewhere,' is characterized by the loss of ability to synthesize p-aminobenzoic acid. This "aminobenzoicless“ mutant is differentiated from normal by a single gene, is unable to grow on unsupplemented synthetic medium, but its growth is indistinguishable from normal when p-aminobenzoic acid is supplied. Each gene codes for a specific and unique protein 1958 – Nobel Prize One-Gene/One-Polypeptide Hypothesis

30. Central dogma of molecular biology

31. Extracting and using the information Two Steps: 1. 2.

32. Extracting and using the information The information

33. Extracting and using the information An intermediate

34. Extracting and using the information The product

35. Translation – constructing a protein DNA mRNA protein transcription translation

36. Transcription DNA copied into mRNA

37. mRNA single-stranded U instead of T

38. Translation – constructing a protein DNA mRNA protein transcription translation

39. Instructions are coded in the order of the bases

40. 20 amino acids Protein is a polymer of amino acids Instructions are an ordered list of amino acids in protein

41. Each ‘word’ in the DNA-RNA vocabulary is 3 ‘letters’ long One “word”

42. Each ‘word’ in the DNA-RNA vocabulary is 3 ‘letters’ long A ‘word’ is called a codon

43. Triplet Codon: group of 3 bases that specifies an amino acid

44. The Genetic Code -Redundant -Not ambiguous -Stop codons -AUG - start -Universal (nearly) Marshal W. Nirenberg

45. The Dictionary

46. Punch tape

48. Ribosome mRNA tRNA

49. tRNA brings in the amino acides

50. Translation

60. Universal (nearly)

61. Reading frames

62. the red dog ate the bug Reading frames her edd oga tet heb ug