2. 1 Gene transcription,post- transcriptional processing & reverse transcription

3. 2 1.Concept A. Enzymes involved in transcription a. RNA polymerase ( DNA-dependent RNA polymerase,DDRP )

4. 3 require: (1) four NTP (2) Mg 2+ or Mn 2+ (3) DNA template (4) synthesis direction

5. 4 Products: single strand RNA containing DNA heredity information

6. 5 RNA pol in prokaryotes ( E.coli RNA polymerase ) * functions * constitute four subunites

7. 6

8. 7

9. 8 core enzyme & holoenzyme RNA pol in eukaryotes

10. 9

11. 10 RNA pol in eukaryotes

12. 11 Type I II III location nucleoli nucleoplasm ucleoplasm products 18s,5.8s, pre-mRNA, RNA,5sRNA 28s rRNA hnRNA U6 sensitivity none +++ + to a amantin

13. 12

14. 13 B. Process of transcription initiation, elongation, termination a. the initiation stage promoter * concept * characteristics

15. 14

16. 15 *Promoter of prokaryotes -10bp-------TATAAT (TATA box) (pribnow box) -35bp------- TTGACA

17. 16

18. 17 Promoter of eukaryote -25bp-------TATAAT (TATA box) (hogness box -40bp------- GCbox -110bp-----CAAT box

19. 18 -110-40-25+1 CCAAT box GC box TATA box

20. 19

21. 20 GC or CAAT box both in sense or antisense strand all effective

22. 21 antisense strand (template strand, (-)strand,) Sense strand (coding strand,(+)strand)

23. 22

24. 23 DNA: antisense 5’AACGTTACCGATC 3’ 3’TTGCAATGGCTAG 5’ sence mRNA UUGCAAUGGCUAG

25. 24 synthesis direction 5’ 3’ characteristic of transcription----- asymmetrical transcription

26. 25

27. 26 enhancer *concept * characteristics

28. 27 cis -acting element *concept trans-acting element *concept

29. 28

30. 29 b.elongation stage the transcription products elongate along the 5’to 3’

31. 30 the RNA pol moves along the 3’ to 5’ 50 nucleotides/second/per molecular enzyme

32. 31 newly synthesis DNA-RNA hybridized strand is unsteadiness

33. 32

34. 33

35. 34

36. 35

37. 36 C.termination * concept *the type of termination a.Rho(  )-dependent termination

38. 37 *the structure of Rho factor *the functure of Oho factor

39. 38

40. 39

41. 40 b.Rho(  )-independent termination the special region in the DNA template

42. 41

43. 42

44. 43

45. 44

46. 45 B.inhibitors of transcription E.summarize a.RNA pol b.process

47. 46

48. 47

49. 48 initiation elongation termination c. characteristics of transcription

50. 49 d. the different of mRNA transcription in prokayotes & eukaryotes

51. 50 Prokaryotes eukaryotes Policistronic transcript monocistronic transcrip Transcription coupled with translation seprate No processing processing Shorter half life longer half life

52. 51 C.post –transcriptional processing in eukaryotes 1.processing of mRNA (1) capping of mRNA

53. 52 * The structure of cap m GpppG * The process of capping *the functure of cap

54. 53

55. 54 (2) Added poly A tail in mRNA 3’end * The structure of tail * The process *the functure of tail

56. 55

57. 56 (3) Splicing remove intron, join exon, mature mRNA

58. 57

59. 58

60. 59 snRNA & snRNP exit RNA processing event

61. 60 (4) RNA editing * concept * significant

62. 61 2.processing of rRNA * quantity * type & arrangement * site * process of processing

63. 62

64. 63 Ribozyme discovery concept structure functure

65. 64

66. 65

67. 66

68. 67 3. processing of tRNA * remove 5’end sequence * CCA is added in 3’end * multiple internal bases are modified

69. 68

70. 69 D. reverse transcription 1.retrovirus & reverse- transcriptase (1) History 1964 Temin

71. 70

72. 71 found RNA virus 1970 found reverse - transcriptase (2) The function of reverse - transcriptase

73. 72 RNA as template Four dNTP Produce DNA containing RNA heredity information

74. 73 reverse – transcriptase (RNA dependent DNA polymerase,RDDP) its function: RNA dependent DNA polymerase RNA hydrolyse DNA-dependent DNA synthetase

75. 74

76. 75 (2) Genome of ASV

77. 76

78. 77

79. 78 (3) Life cycle of retrovirus two stage: * RNA reverse transcription DNA provirus intergrate into host cell

80. 79 * DNA transcription mRNA Protein virus particles

81. 80

82. 81 2.oncogen& tumer suppressor gene (1) concept of oncogen & pro-oncogen

83. 82 (2) proto-oncogen become oncogene *enhanced expression *mutatiom

84. 83 (3) Products &function of pro-oncogene * grows factors *trans-membrane receptors *transducers in the cell *transcriptional factors