Central Dogma

1
????????????????????????????
Central Dogma
2
???????????? - ???????????????????????????????????
structural sequence - ??????????????????????????
???????????? regulatory sequence promoter ????
5 ??? ss terminator ???? 3 ??? ss
3
????????????????
Polycistronic gene 1 ??? regulatory
sequence ???????? (??????? structural sequence)
4
????????????????
Promoter ?????????? 6 ???????????? ??????? 35
??? 10
5
????????????????
????????????? ???????? ???? ?????????? ???????
RNA polymerase ??????????????? ?????????????????
??????????
6
????????????????
RNA 1 ??????? ??????????????????? ???????????????
?????????????? promoter ??? terminator
7
???????????????
Monocistronic gene 1 regulatory sequence 1
structural sequence / gene 1 mRNA 1 protein
8
???????????????
Structural sequence exon ???????????????????????
?? expressed region intron ?????????????????
??????????? intervening sequence
9
???????????????
???????????? intron ???????????????????????
10
???????????????
Promoter TATA box / Hogness box ????????????????
???? RNA polymerase
11
???????????????? Gene Expression
???????????????????????????????????? ?????????????
?????????????????????????????? ???????????????????
??????????????
12
??????????
RNA ribonucleic acid Polynucleotide single
strand
?????????? ??? ???????? Purine, Pu ???
????????? Pyrimidine, Py ?????? ????? Ribose
(2-OH) ?????????? Phosphate group
13
??????????
???????????
????????????
??????? Adenine, A
??????? Cytosine, C
?????? Guanine, G
??????? Uracil, U
14
??????????
???????????????????? ???????????????
???????????????????????? ????????????
???????????????? ?????????????????????????????????
??????????
15
?????????????????????????? ??????????????
Messenger RNA mRNA ???????????????????? Ribosomal
RNA rRNA ???????????????????? Transfer
RNA tRNA ??????????????????????????
16
???????????????????????
??????????
- ??????????????? ???????????? Double stranded
DNA, dsDNA - ??????? RNA polymerase -
???????????? NTPs ATP, GTP, CTP,
UTP ??????????????????
17
???????????????????????
????????? transcription ??????????????????????????
??????? ????????????????????? ????????? 3 ??
5 ??????????????????? ??? ?????????????? ???????
????????? ????????? 5 ?? 3 ????????????????
?????????????? ???????????????????????????????????
??????
18
???????????????????????
????????????????????????????? ???????????????????
????????????????????? template / noncoding /
antisense strand ????????????????????????????? ??
????????????????????????????????????? nontemplate
/ coding / sense strand ?????? T ???????????
U
19
????????? transcription
20
????????? transcription
21
????????? transcription
22
???????????????????????
??????????????????????????????????????????? nucle
ar RNA, pre-mRNA primary transcript ??????????
exon ??? intron ????????? RNA processing ????????
??????????????????????????????? ?????????????????
????????????????
23
???????????????????????
?????????? 3 ???????
5 Capping ???? 7-methyl guanosine
nucleotide Splicing ??? intron ??? ??????? exon
??????????? 3 Polyadenylation ???? poly A tail
(100-250 A residues)
24
???????????????????????
mRNA, mature RNA, mature transcript
25
???????????????????????
????????????????????? (cap and tail) ?????????????
??????????????????? ????????????????????????????
?????????????????????????????????????? ???????????
?????????????????????? ????????????????????
translation
26
???????????????? ???????????? ??? ?????????
27
?????????????????????? mRNA ???????????? ???
?????????
28
???????????????????
????????? translation ??????? / ???
???????????? ??????????????????????????? ?????????
????????????
????????????? ???? genetic code ?????????????? 3
??? (1 codon) ???????????????? 1 ????
29
???????????????????
????? ?????????????????????? 3 ??????? ???????????
?????? 4 ???? (A, U, C, G) ?????????????
(444) 64 ???
???????????????????? (translation
initiation) start codon AUG
methionine ??????????????????? (translation
termination) stop codon UAA, UAG, UGA no aa
30
???????????????????
???????????????????????????????? 61 ??? ??????
????????? 20 ???? ????????? 1 ???? ??? 1
????????? ???????????????????? 1 ???? ?????? 1
aa degeneracy of the code degenerate codon
5 AUG GUC GCC ACG CCG UCG UAA 3 Met Val
Ala Thr Pro Ser Stop
31
Genetic Code Table
32
???????????????????
??????????
mRNA genetic code Ribosome alignment tRNA amin
o acid carrier others
33
???????????????????
????????????????
??????????? ??? ?????????
34
Ribosome
rRNA rProtein Small subunit Large subunit
35
(No Transcript)
36
(No Transcript)
37
???????????????????
Small subunit ?????????? ????? mRNA Large
subunit ?????????? ???????? tRNA ???????
??????????????? ???????????? AUG
38
???????????????????
tRNA ?????? Methionine ???????????????????????? P
site ?????????????? start codon tRNA
??????????????? ???????? ???????????????? ????????
????????? A site Peptide bond formation
39
???????????????????
??????????????????????? 3 ??????? 1 ????? tRNA
???????????????????? E site tRNA
?????????????????? ??? stop codon ?????
tRNA ????????????????? ??????????????
40
??????
Amino terminal ---------- Carboxyl
terminal ??????????? ?????? 5 ----------- 3 ??
mRNA Protein folding ????????????????????????????
????? ????????????????????????????????????????????
????????
41
????????????????????????????
Central Dogma
42
Reverse transcription
???????????????? RNA ???? DNA ??????? reverse
transcriptase ?????????? dNTPs
43
????????????????????????? Control of gene
expression
???????????????? ????????????????? ?????????????
??????????????????? ????????????????????????????
?
44
?????????????????????????
Housekeeping genes ???????????????
??????????? Specific/Inducible genes ????????????
??? ??????????? ???????????????????????? (??????
- ????????????)
45
?????????????????????????
Transcriptional control

• Transcription switch on/off
• ?????????????????? ???????? ??? ??????
• ???????? ??? ???????????????? 5 ??? TATA box
• ?????? ??? Transcription factor
• ?????????????????????????????????????????????????
• ?????????? ???? ???????????????????????????????
  TATA box

46
?????????????????????????

• ????????? ????????????????????????
• ?????????????????? ???????? ??? ??????
• Enhancer/ Repressor
• - ????????????? mRNA

47
?????????????????????????
Translational control - ?????????????????????????
???????? - ????????????????????? -
??????????????????? ????? - ??????????????