Parvovirus

Question 1

parvovirus structure

Answer 1

small capsid (parvus). simple structure, naked icosahedral capsid (t=1). coat protein: 8 stranded antiparallel beta barrel shape

Question 2

parvovirus characteristics

Answer 2

ssDNA linear. 5kb genome. small virions (28nm).

depend on host DNA replication so needs S-phase.

Question 3

types of parvoviridae

Answer 3

densovirinae (insects etc)
parvovirinae (mammals)
- Autonomous replicating viruses (only need dividing cells) ss(-)DNA
- dependoviruses (need adono or herpes coinfection). AAVs either - or + ssDNA

Question 4

genome organization of parvoviruses

Answer 4

replication proteins (NSs/Rep) and capsid protein (Cap/VPs). MVM use 2 promoters one for repl. and one for cap. AAV uses 3, two for repl. and one for cap.

Question 5

DNA replication of parvoviruses

Answer 5

usage of hairpins so that the full DNA can be replicated. after replication endonuclease site creates a free 3’ end. hairpin unwinds and DNA polymerase continues. hairpin refolds and ssDNA unfolds.

Question 6

non structural protein of parvovirus

Answer 6

NS1:
- transcriptional activators
- Site specific endonucleases
- ATP binding, ATPase and helicase activity
- Induce cell cycle arrest
- oncolytic properties
NS2: Efficient Nuclear Egress of Progeny Virions