Download structure of RNA

Metabolism of nucleic acids
the structure & function
The structure of nucleic acids
1.summarize
the discovery
The function
The headway
A. nucleotides
base（purine、pyrimdine）+ribose（deoxyribos
N-glycosyl linkage
nucleoside+phosphate
phosphoester linkage
nucleotide
phosphodiester linkage
nucleic acid
B. The structure of the
nucieic acid
一、the
building block molecule of
nucleic acid--nucleotide
In RNA:
AMP、CMP、GMP、TMP
In DNA:
dAMP、dCMP、dGMP 、dUMP
The physiological function
of the nucleotides
二、the
linkage ----
phosphodiester bridge
3’terminal
5’terminal
Nucleotide residues
三、the
primary structure of nucleic
acid
definition
writing method
polinucleotide
oligonucleotide
四、the
structure of DNA
1.the primary structure of DNA
* concept
* writing method
5’-AATTCGGATCTTAGC-3’
* characteristics
specificity in race
non specificity in tissues
Chargff Law
2.the secondary structure of DNA
Watson-Crick double helix
structure
3.the force maintaining the
double helix stability
* hydrogen bond
* Stacking force
4. Some difference
steric
conformation types
of DNA double helix
A型
B型
75%
92%
高盐溶液结晶
方向
右手
右手
左手
直径
2.55nm
2nm
螺距
2.46nm
3.4nm
0.23nm
0.34nm
结晶湿度
相邻碱基距离
螺旋一周所含
碱基
11
10
Z型
表面只有一大
沟碱基为嘌啉
呤，嘧啶交替，
12
5. The tertiary structure
of nucleic acid
The length of genome DNA
6106Kb
DNA supercoiling
The basic structure of
chromosome --- nucleosome
Nucleosome
（ DNA double helix of containing 200bp ）
140bp DNA double
helix
histone
(H2A1)2,(H2B)2,(H3)2,(H4)2，octamer
Core particles
60bp DNAdouble helix fragment+H1histone（linkage region）
Core particles
a string of beads of nucleosome
further fold to form chromosome
五、the
structure of RNA
1.summarize
•
Content
• components & linkage
• inhomogeneity
• steric conformation
• function
2. The structure of tRNA
* kinds
* commonness
(1) The primary structure
of tRNA
* 5’ PG, 3’ CCA
*
more rare bases
(2) The secondary structure
of tRNA
Characteristic structure
*Amino acid arm
* DHU arm
DHU ring
* T ψC arm
TψC ring
•Anticodon arm
anticodon ring
extra fork
(3) The tertiary structure
of tRNA
twisted L
3. The structure of mRNA
(1) Summarize
* characteristic
Prokaryotes --polycistronic
Eukaryotes-- monocistronic
(2) The characteristic of
Prokaryotes mRNA
(3) The characteristic of
eukaryotes mRNA
Heterogeneous nuclear
RNA, hnRNA
•
Concept
• characteristic
The structure of 5’ Cap
(7mG5’ppp5’Np)
The function of 5’cap
The structure of 3’ tail
( Poly A)
The function of 3’ tail
4. The structure of rRNA
(1) Summarize
prokaryotes
eukaryotes
Type
5s, 16s,23s
The number
120 ,1542 ,3200 120,160,1940,4718
of nucleotides
5s,5.8s,18s,28s
prokaryotes
eukaryotes
5s,23s
Large 50s
Subunit
Small
subunit
5s,5.8s,28s
60s
34rP
49rP
16s
30s
18s
40s
21rP
33 rP
Total size 70s
80s
diameter 8nm
diameyer 23nm
Shine-dalgarno sequence in
16s RNA (initiation sequence of
protein synthesis in prokaryotes
conservation sequences of
5sRNA and 5.8sRNA can
recognise TψC ring in tRNA
The physic-chemical
propertices of nucleic acids
1. size
2. Hydrolysis of nucleic acids
3.denaturation,renaturation,
hybridization
a. denaturation,
*concept
* hyperchromic effect
mechanism
* melting curve
• melting temperature (Tm)
Concept
characteristics
b. Renaturation (annealing)
Concept
characteristics
hypochromic effect
mechanism
c. Hybridization
concept
Gene & genome
• Concept of gene
• classification of gene
• concept of genome
• gene family
• split gene
• pseudogene