DNA Virus 1 Flashcards Preview

Micro/Immuno Part 2 > DNA Virus 1 > Flashcards

Flashcards in DNA Virus 1 Deck (26):
1

key concepts of DNA viruses

-transcription and replication in nucleus (except pox)
-host RNA pol II transcribes mRNA (except pox)
-viral or hose DNA pol replicates genome

2

parvovirus

-BK virus

3

papova

warts
cancer

4

adeno

colds
keratitis

5

hepadna

hep B

6

herpes

cold sores, etc

7

pox

smallpox

8

DNA genomes

-small circular DNA
-ejected various ways into the nucleus-see slide

9

steps in DNA virus replication

1. recognition
2. attachment
3. entry
4. uncoating
5. transcription of mRNA-Host RNA pol
6. protein synthesis
7. replication of the genome- host or viral DNA pol
8. assembly of virions
9. egress

10

use of host RNA pol for mRNA transcription

-DNA viruses use the host RNA pol
-RNA pol II and TF (x,y) recognize viral promoters
-X and Y are proteins that enhance viral transcription

11

TFs

-both cellular and viral factors regulate transcription by host RNA pol
-viral TFs are important virulence factors and are probably essential
-need cells to recognize viral TFs and promoters in order to transcribe them

12

genome synthesis-host DNA pol

-some virus genomes are recognized by the host DNA pol complex
-these viruses do not encode their own polymerase-small genomes
-parvovirus-adeno associated virus 2
-need to be in dividing cells

13

genome synthesis-viral DNA pol

-large DNA viruses encode their own pol and accessory proteins
-herpes, adeno
-don't have to be in a replicating cell

14

origins of diversity in DNA viruses

-recombination between and within genomes
-DNA pol have higher fidelity than RDRP
-mutations about 1/ 1 mil- like us
-genetically more stable than RNA viruses

15

adenovirus diseases

-resp-bad cold/fever, pharyngoconjunctival fever, laryngitis and cough, pneumonia
-other sites-acute hemorrhagic cystitis, epidemic keratoconjunctivitis, gastroenteritis

16

adeno epidemeology

-aerosol, fecal oral, objects
-poorly chlorinated pools
-children
-military recruits
-daycare centers, swimming clubs, boot camp

17

adenovirus life cycle

-adeno fiber protein binds to cell receptor
-entry by endo
-endosome acidification causes fibers to lyse the vesicle
-capsid traffics to nucleus and DNA genome uncoats through nuclear pore
-genome replicates in nucleus
-host RNA pol II makes mRNA
-immediate early, early, late
-genome replication by viral DNA pol
-capsid assembly in nucleus
-virions egress by lysis

18

gene expression phases in adeno

-immediate early for EIA
-helps make more mRNA
-early for DNA pol, which replicates genome
-late for structural proteins- for assembly

19

adenovirus diagnosis and treatment

-match the diagnostic test to the patient sample
-culture, antigen detection, PCR, serology
-treat immunocompromised patients with cidofovir-dire cases and nephrotoxic

20

adeno prevention

-vaccine
-used only for military personnel
-reinstated for use in late 2011
-incidence of Ad4 infections plummeted

21

HPV diseases

-common
-epithelial disease-common, plantar, genital warts
-malignancies-head and neck cancer, cervical cancer, penile cancer

22

HPV tissue tropism

-differentiated epithelial cells
-infects basal cells, limited amplification and maintenance replication until to top layer, then productive replication

23

HPV infection

-cut
-productive life cycle for 2-3 weeks,grows up with skin
-growing cells express E7/E6, virus sheds
-lack of immune clearance
-skin becomes overgrown with HPV infected cells- oncogene activation
-causes invasive carcinoma

24

HPV DNA replication

-host RNA pol transcribes viral mRNA
-host DNA pol synthesizes viral genomes
-viral factors E6 and E7 are oncogenes

25

HPV diagnosis and treatment

-diagnosis for genital HPV is recommended-DNA tests for type, important to screen for 13 high risk types linked to cancer
-treat warts by excision- freezing, chemical ablation, coposcopy
-treat malignancies with oncotherapy

26

HPV vaccine

-gardasil-quadrivalent for 6,11,16,18
-ceravix is 16,18
-both are virus like particles-empty capsids- makes antibodies to L proteins in genome