DNA Viruses 1 Flashcards
What are two DNA viruses?
Adenovirus, papillomavirus
Where does txn and replication of DNA virus genomes occur? What is the excetion?
Nucleus
Poxvirus
What enzyme transcribes the DNA virus mRNA? What is the exception?
host RNA pol
Poxvirus
What enzyme replicates a DNA viral genome?
viral OR host DNA pol
What are the steps in DNA virus replication?
Recognition of target cell Attachment Entry: Penetration or Fusion Uncoating Transcription of mRNA (host RNA Pol) Protein synthesis Replicate genome (host or viral DNA pol) Assembly of virions Egress: lysis, budding, exocytosis
How does a DNA virus enter a cell?
Penetration or Fusion
How do DNA viruses egress?
lysis, budding, or exocytosis
What host machinery recognizes viral promoters?
RNA Pol II and txn factors (X,Y)
What to viral txn factors do?
Work WITH host txn factors
also virulence factors
might be essential proteins
What is an example of a virus which uses host DNA pol for replication? How is this virus characterized?
Parvovirus
Adeno-assiciated virus 2
Do DNA viruses which use host/virus DNA Pol have small/large genomes?
use host - small genome - don’t encode
use own - large genome - encode enzyme
What are examples of viruses which encode their own DNA pol?
Herpesvirus
Adenovirus
What DNA viruses are the most common causes of disease?
Adenovirus
Papillomavirus
Herpesvirus
What respiratory illnesses does the Adenovirus cause?
bad cold with fever
pharyngoconjunctival fever
laryngitis and cough
pneumonia
What non-respiratory illnesses does the Adenovirus cause?
Acute hemorrhagic cystitis
Epidemic keratoconjunctivitis
Gastroenteritis
What is the transmission of the Adenovirus?
aerosol, fecal-oral, objects
poorly chlorinated pools
What populations are susceptible to adenovirus?
children
military recruits
What are sites of outbreak of the adenovirus?
daycare centers
swim clubs
“boot camp”
How does the adenovirus bind to the cell receptor?
fiber protein
How does adenovirus enter the cell?
Endocytosis
After endocutosis, how does adenovirus get out of the vesicle?
endosome acidification lyses vesicle
When and where does adenovirus uncoating happen?
after edosome is lysed, capsid goes to nucleus
DNA genome uncoats through nuclear pore
What are the gene expression phases of adenovirus?
Immediate early
Early
late
Where does the adenovirus capsid assemble?
nucleus
How do adenovirus virions egress?
lysis
What is the diagnosis of adenovirus?
culture
antigen detection
PCR
serology
What is the treatment of adenovirus?
Only treat dire cases in immunocompromised patients
Cidofovir (but it’s nephrotoxic)
How is adenovirus prevented? What population receives this?
Vaccine
military personnel
What is the most commonly diagnosed STI in the US?
HPV
What epithelial diseases does human Papilloma virus cause?
Verruca vulgaris (common warts) Verruca planaris (plantar warts) Condyloma acuminata (genital warts)
What malignancies does human papilloma virus cause?
head and neck cancer
cervical cancer
penile cancer
What is the tissue tropism of HPV? What layer must it reach?
differentiated epithelial cells
basal
How does HPV-induced malignancy occur?
oncogene activation
How many types of HPV are high risk for cancer?
13
What is the diagnosis of HPV?
recommended for genital
DNA test for type
What is the treatment for warts?
Excision
- cryotherapy (freezing)
- chemical ablation (salicylic acid, etc)
- colposcopy (minor surgery of cervix)
How are HPV malignancies treated?
oncotherapy
what is the prevention of HPV?
vaccines
- Gardasil (6, 11, 16, 18)
- Cervarix (16, 18)
How were the vaccines for HPV created?
both are VLP’s (virus-like particles)
empty capsid
