General features of viruses and notable exceptions Flashcards
All DNA viruses encode _____(1)_____ except _____2 and 3.
DNA dep DNA polymerase
Except: papilloma, polyoma, and parvo
replication in cytoplasm instead of nucleus (DNA virus)
pox- also has DNA dep DNA polymerase in core
Herpesviruses- any exceptions here?
encodes thymidine kinase (this phosphorylates acyclovir the first time) and has three classes of transcripts (alpha, beta, gamma)
HepB virus exceptions
cytoplasmic replication (I think within the core), contains reverse transcriptase, DNA from RNA (hence reverse transcriptase)
Usually DNA virus replication have early and Late transcripts–what are the exceptions?
Parvoviruses (B19)
HepB
dsRNA replication
Reoviridae
Replication in core using + RN, has early and late transcripts
+ssRNA replication
genome made from -RNA (duh, otherwise it wouldn’t be +)
translation= polyprotein and needs proteases to make RNA polymerase
What +ssRNA has early and late transcripts?
togaviruses
-ssRNA
Exception?
has RNA dep RNA pol
make + rna and then transcribe/translate
Exception: Orthomyx (influenza) replicates in the nucleus and assembles in cytoplasm
Retrovirus
+ssRNA w/ envelope
Capsid has: RNA dep DNA pol (reverse transcriptase) and integrase
1. Make dsDNA from RNA (using RT)
2. dsDNA integrated into host genome
3. transcription of host/viral genome mix
4. RNA made (used in progeny) and then translated to make polyproteins–>cleaved by proteases to make reverse transcriptase and integrase
5. all that shit is packaged into a new virus and leaves the cell
where does herpes get its envelope?
nuclear membrane
Viruses that give you watery diarrhea
rotavirus, norovirus, adenovirus
Infections that pass to fetus (ToRCHeS)
Name virus and outcome
T/S= bacteria (not included)
2H’s
Rubella= cataracts, deafness, patent ductus arteriosus, deafness, blueberry muffin rash
CMV- hearing loss, petechial,
HIV- Recurrent infections, chronic diarrhea
He= HSV2= encephalitis, vesicular herpetic lesions
