RNA?????

1
? ? ? ?
RNA????? (??) RNA Biosynthesis, Transcription
2
?? (transcription)

• ????DNA?????RNA??? ? ????DNA????????RNA??????

??
3
?????????
??? ???
??
?? ?DNA??? ????
??? ?4?NTP dNTP
NTP ???? AT
AU,TA ????5?3 ??DNA????
DDDP DDRP ???????? ??????
mRNA?
tRNA?rRNA
4
???????
?? NTP (ATP, UTP, GTP, CTP) ?? DNA ?
RNA???(RNA polymerase, RNA-pol) ???????
5
???
???? Templates and Enzymes
6
??????

• ????strucural gene
• ????mRNA????????? ????
• ???template strand
• ????????RNA?????????????Watson??
• ???coding strand
• ???????????????????Crick??

7
?? ??????????

• 5 GCATTAGCTAGCTACTAGC 3 DNA
• 3 cgtaatcgatcgatgatcg 5 ??
• ??
• 5 GCAUUAGCUAGCUACUAGC 3 mRNA
• ??
• N Ala?Leu?Ala?Ser?Try C ??

8
???????

• ?????asymmetric transcription
• DNA?????????,?????,???????
• ???????????

9
????
5? 3?
3? 5?
???
???
???
???
10
?? RNA???

• ?????DNA?RNA???
• DNA dependent RNA polymerase
• DDRP

11
?????RNA???

• ?????RNA????2???
• ???2?????????????
• ??????????
• ? ?2????
• ?????????(?????)???????

12
??? (core enzyme)
?? (holoenzyme)
13
RNA??????????????
14
?????RNA???
?
15
?????RNA???
RNA???II?????????????RNA???
16
???????????
???????????????????,?????(operon),?????????????(up
stream)??????
RNA???????DNA???,?????(promoter)?
17
???????????

• ????????
• ?????????
• -35bp?????5-TTGACA-
• -10bp?Pribnow? 5-TATAATPu
• ?????????(?-30?Hogness?TATA?)?

18
RNA??????
? ?
19
????
-35 ?
-10 ?
T T G A C A A A C T G T
T A T A A T Pu A T A T T A Py
RNA-pol???? (recognition site)
(Pribnow box)
???????????
20
????
-GCGC---CAAT---TATA
???????????
21
???
???? The Process of Transcription
22
???????????
(?)????

• ???????????
• RNA?????????????????????
• DNA????,???????????????

23
??????
1. RNA?????(?2????)?????
2. DNA????
3. ?RNA???????????????,?????????
5?-pppG -OH NTP ? 5?-pppGpN - OH 3? ppi
???????
RNApol (?2????) - DNA - pppGpN- OH 3?
24
????????

• ??
• ??????
• ???????GTP?ATP
• ???????(RNA-?????-DNA-pppGpN-OH)
• ?????????, ?????????????????RNA????DNA??????

25
????(transcription bubble)
RNA-pol (???) DNA RNA
26
(?)????
1. ?????,RNApol????????,???????,??DNA????
2. ???????,NTP????,RNA??????
(NMP) n NTP ?? (NMP) n1 PPi
27
?????

• ???????5?3???????
• (NMP)nNTP?(NMP)n1PPi
• ?GC?AU?TA?????
• ???????DNA???????
• ???RNA????????,????????,?????,??????????

28
(No Transcript)
29
?????
30
?????
31
DNA
RNA
5?
3?
RNA???
???
???????????????
32
(?)?????

• ?????RNA??????????????,RNA?????????????
• ????Rho???????????Rho????????

33
1???Rho???????

• Rho???????RNA-DNA?????????,?????????????????????

34
1. ?? Rho???????
A T P
35
2. ??? Rho???????
DNA????????,?????????,???RNA?,RNA???????????????
36
2????Rho???????
37
DNA
5?TTGCAGCCTGACAAATCAGGCTGATGGCTGGTGACTTTTTAGTCACCA
GCCTTTTT... 3?
5UUGCAGCCUGACAAAUCAGGCUGAUGGCUGGUGACUUUUUAGUCACCA
GCCUUUUU... 3
5UUGCAGCCUGACAAAUCAGGCUGAUGGCUGGUGACUUUUUAGUCACCA
GCCUUUUU... 3
5UUGCAGCCUGACAAAUCAGGCUGAUGGCUGGUGACUUUUUAGUCACCA
GCCUUUUU... 3
RNA
??(stem-loop)/??(hairpin)??
38
????????????

• ?RNA?????,????
• ??????????,RNA?????

39
???Rho?????????
RNA????-???,?? ?????? 1.???????RNA??? ???,????????
? 2.DNA?RNA??????? ????,???????? ?,?????????? ?? ?
??????U,???? ?RNA????????? ?????
40
???????????
(?)????
?????????????????????,?????,RNA-pol???????,???????
??????
41
1. ??????????
???
??????(cis-acting element)
????
AATAAA
???
?????
?????
?????
???
???
TATA?
OCT-1
CAAT?
GC?
OCT-1ATTTGCAT???
42
2. ????
?????????????????DNA????,???????,?????????(trans-a
cting factors)?
???????,???????RNA????,???????(transcriptional
factors, TF)?
43
??RNA-pol????TF?
44
3. ???????? (pre-initiation complex, PIC)
????RNA-pol??DNA??????,????????????
45
?RNA-Pol ??????PIC
TAF
TBP
?B
TATA
?A
TF?D-?A-?B-DNA???
?H
?E
?H
?E
TAF
TBP
TF?F
?B
TATA
?A
PIC????,TF?H?CTD???
46
4. ????(piecing theory)
?????????????3?5????????????????,?????,????????,??
RNA??????????????????????
47
(?)????
???????????????????,???????,?????????????
RNA-pol???????????
???????????????????????
48
???????????
???
RNA-Pol
????
RNA-Pol
RNA-Pol
49
(?)????
???????????
AAAAAAA 3? mRNA
5? ------AAUAAA--
3???
5?------AAUAAA-
???
-GUGUGUG
RNA-pol
5?
3?
AATAAA GTGTGTG
5?
3?
????????
50
???????????

• ????mRNA???????????,??????????
• ?????????3???,????????AATAAA,?????????GT??,??????
  ?????????

51
??????????

• ??DNA???
• ????????,?5?3???????????????
• ?????????
• ?????DNA????
• ???????????

52
????????
53
???
?????????? Post-transcriptional Modification
54
??????

• ?????RNA,?????????
• ?????????????,??????????????????,????????

55
?????????
2. ??(cleavage)
1. ??(splicing)
3. ??(modification)
4. ??(addition)
56
??????mRNA??????
(?)??????

• 5???? ????(m7GpppGp )
• 3???????????(poly A tail)

57
????
58
???????
5? pppGp
59
????mRNA??????

• 5?3?????
• ??

60
5??

• ???????????pppG???5-ppG?5-pG
• ?????????????????
• ??????????
• ?????hnRNA?,???????????,???????

61
3?????????

• ????mRNA?poly A????????DNA????
• ??poly A??,?????????3??????????,????polyA?
• 3??????????,?????????
• Poly A??????,???mRNA?????????,????mRNA???????

62
3??????
63
(?)mRNA???
1. hnRNA ? snRNA

• ?????mRNA?????RNA (hetero-nuclear RNA, hnRNA)
• snRNA (small nuclear RNA)

64
????(splite gene)
????????,?????????????????????????,??????????,????
??????????????,???????????
??? A?B?C?D
65
2. ???(exon)????(intron)

• ???
• ????????????????,??????RNA??????
• ???
• ?????????????????????????

66
?????????????????
???????
hnRNA
?????
hnRNA??
???mRNA
67
mRNA
DNA
???????mRNA?DNA?????
68
????mRNA???

• DNA???hnRNA??????,????mRNA?hnRNA?DNA??????????
• ??????????????

69
????

• ?????????,?????????????????,????????,?????????????
  ???
• ?????????????????????
• ??????????????
• ????????????????,???????

70
??????

• ???,???????rRNA??
• ???,????mRNA
• ??????????,?SnRNA????????????????????
• tRNA???

71
3. ??????
?????????????,????????4??
I?????????????????????? rRNA?? II???????????,??
???mRNA III?????????????,???mRNA????????
IV?tRNA???????????????,???????ATP?
72
4. mRNA???
??hnRNA?????,???????

• snRNP?hnRNA???????

?
73
?
?
74

• ???????????
• (twice transesterification)

pG-OH (ppG-OH, pppG-OH)
75
5. mRNA???(mRNA editing)

• RNA??????,??????????????,?????????,?????????(dif
  ferential RNA processing)?

76
??????

• ?????????????
• ????

77
tRNA??????

• ??????5??16??????????14????????

78
??tRNA??????
tRNA??
79
(No Transcript)
80
tRNA??????????
ATP
ADP
81
????
82
???????

• ???
• ??
• ????????
• ????
• 3???CCA-OH

83
??rRNA??????
84
rRNA??????

• ??????????????????????????????
• ?????rRNA?????????
• 45s????????rRNA???,??????????????18S
  rRNA,????5.8S?28S?rRNA?

85
???rRNA???
86
???rRNA???????????
???rRNA????????
5-??????
87
??(ribozyme)

• ??RNA????????,???RNA????????,?????
• ????????????

88

• ?rRNA?,tRNA?mRNA??????????????

• ???????????????
• (hammerhead structure)

• ???60??????
• ?????????????????
• ???????????????

????
89
???????

• ??????????
• ?????????
• ?????????????

90

• ???????

• ?????,???????????
• ??????????????
• ??????????????? ?

91
???????

• ???????????
• ???????????
• X ???????
• ???????

92
??
93
???RNA?????