Parvovirs

Parvoviruses
· Subfamily Parvoviridae has three genera - Parvovirus, Erythrovirus (Human B19 virus), Dependovirus (Adeno-associated virus 2)
· This subfamily is mainly realted to animals and humans.
· Parvovirus occur mainly in humans and in mice
· Erythrovirus only occurs in humans
· Dependovirus need other viruses such as herpes to be able to complete is replication cycle and itsused in gene therapy
· New genera of viruses include Amdovirus (Aleutian mink disease virus) and Bocavirus (Bovine parvovirus) which occur in humans and cows
· Subfamily Densovirus also has three genera - Densovirus (Junonia coenia densovirus), Iteravirus (Bombyx mori densovirus), Contravirus or Brevidensovirus(Aedes aegypti densovirus)
· All of these including Pefudensovirus (Periplanetafulginosa densovirus) occur in insects
· The viruses in the parvoviridae family have Greek and Latin roots
· Adeno - gland
· Brevi - short
· Depedo - to hang down
· Entomo - insect
· Erythro - red
· Denso - thick, compact
· Parvo - small
· B-19 is very related to other parvoviruses such as the macaque
· Adeno-associated virus are related to each other from 1 to 6 and itdoesn't cause any disease in humans since is used in gene therapy. very important which to choose for gene therapy depending on wheater they are very close or far related to each other
· Canine is very closely related to the feline virus and the mink enteritis virus which are more closel related
· Human bocavirus has been identified as the cause of pneumonia and they are closely related to oneanother such as strains in bacteria
· Parvoviruses are naked, icasohedral nucleocapsids. They are around 18 - 26 nm and contain 60 capsomeres. They have ssDNA + or - and encapsilated, It's only 1.5 to 2.0 10^6 daltons (5,000 nucleotied) long. It also contains inverted complementary sequences at the ends which are involved in priming
· The inverted repeats of the autonomous viruses are different fromeach other in comparison to the dependovirus that depend on viruses such as adeno or herpes virus to replicate and they require their transforming functions.
· The multiplication of the autonomous viruses is a productive or lytic infection and they bing to heparin sulfate proteoglycan cell receptor and fibroblast growth factor receptor??
· Absorbtion, penetration, uncoating, DNA to nucleus,replication, production of proteins, assembly and release of completed particles
· The Adeno-associated viruses have a different replication cycle can be lytic or lysogenic
· They will enter the cell on their own, they will replicate and integrate into the chromosome (chromosome 19), and the cells will divide. If at the same time the cell is infected with an adenovirus you can produce productiveinfection and will get complete replication and release of complete virus particles. And if the adeno-associated virus is integrated into the genome and then infected with a adenovirus it will replicate infectious perticles. The replicase binds to the region of the inverted repeat tha is double stranded.
· Adeno-associated viruses there are basically two genes associated with it, replicase and acapsid. There are four REP gene products with DNA binding, endonuclease, ATPase, helicase and ligase. There are two capsid gene products, VP1 and VP2 & VP3
· B19 has a lot of parts of its genes that will be spliced to form the final product. B19 can have the power to alter the function of the cell
· The parental DNA is ssDNA and at the inverted repeats at the end, hairpin structures are formedwhich serve as a region to start adding nucleotides and then the gap has to be filled since they are cut.
· NS1 is a packaging protein that is not a part of the capsid and it binds to one end of the single stranded DNA, it guides unit length DNA to the capsid, then it is cleaved from the ssDNA allowing completion of nucleoid capsid. This protein has been a targt to pharmaceuticals so it doesn't...