病毒增殖

32
Release
Lysis裂解
Байду номын сангаас
1
2
Budding through plasma membrane
33
Semliki Forest Virus塞姆利基森林病毒 Budding
Schaechter et al, Mechanisms of Microbial Disease, 3rd ed, 1998
2
ADSORPTION
3
ADSORPTION
• Temperature independent • Requires viral specific binding site • Cellular receptors细胞的受体
4
Significance
The specific attachment determines the host range（属主 范围） of the virus: :
• Need to make genome available
• Once uncoating occurs, enter eclipse phase
22
UNCOATING
• Need to make genome available
• Once uncoating occurs, enter eclipse phase
•
（核） or cytoplasm（胞浆）
Protein synthesis is always in the cytoplasm
25
Synthesis
the production of early mRNA & early proteins the replication of genome the production of late mRNA & late proteins
15
Penetration
Enveloped Viruses
from Schaechter et al, Mechanisms of Microbial Disease, 3rd ed, 1998
16
Penetration
NON-ENVELOPED VIRUSES
17
Penetration Naked virus
• Eclipse phase lasts until first new virus particle formed
23
24
Synthesis合成 Viral Nucleic Acid & Protein
• Many strategies（多种策略） • Nucleic acid may be made in nucleus
28
3. (-) Single-stranded RNA viruses
Paramyxovirus 副粘病毒
29
4.Retroviruse
nucleus (provirus，前病毒)
(provirus)
HIV,HTLV-l
30
Assembly & Maturation
Nucleus Cytoplasm At membrane
• Species（种特异性） • organ specificity（器官特异性）
5
Penetration Enveloped Viruses
• Fusion with cell membrane
• Entry via endosome（经内吞体）
6
Penetration
herpesviruses, paramyxoviruses, HIV
Viral multiplication 病毒增殖
1
Basic Steps of Viral replication Cycle 病毒的复制周期
• • • • • • Adsorption吸附 Penetration穿入 Uncoating脱壳 Biosynthesis生物合成 (eclipse phase隐蔽期) Assembly装配& Release释放
31
Smallpox Virus天花病毒 Assembly & Maturation
F. A. Murphy, School of Veterinary Medicine, University of California, Davis. http://www.vetnet.ucdavis.edu/fam_ graphics/ downlo ad. html
7
Penetration Enveloped Viruses
• Fusion with cell membrane
• Entry via endosome
8
9
10
11
12
13
14
Penetration
Enveloped Viruses
• Fusion with cell membrane • Entry via endosomes, fusion with acidic endosome membrane
entry directly across plasma membrane
18
Penetration Naked virus
entry directly across plasma membrane
19
20
UNCOATING
• Need to make genome available
21
UNCOATING
34
HIV Budding & Maturation
Hsiung, GD et al., Diagnostic Virology 1994 p204 (D. Medina)
35
uninfected
HIV infected
HIV infected (at higher magnifcation)
26
1. ds DNA virus
Cytoplasm`
nsp
nucleus
sp
Herpesviruse 疱疹病毒
27
2. (+) Single-stranded RNA viruses
ribosomes
picornaviruse to serve as a messenger RNA to serve as a template for the synthesis of a complementary (-) strand RNA -- make more (+) RNA strands