| Line 6: |
Line 6: |
| | | | |
| | <categorytree mode=pages>Retroviridae</categorytree> | | <categorytree mode=pages>Retroviridae</categorytree> |
| − |
| |
| − | BLV-HTLV retroviruses
| |
| − | :''Bovine Leukosis Virus''
| |
| | | | |
| | |logo =FeLV logo.jpg | | |logo =FeLV logo.jpg |
| | }} | | }} |
| | | | |
| − | ==Morphology== | + | {{Learning |Vetstream = <p>[https://www.vetstream.com/felis/Content/Bug/bug60015.asp Feline Immunodeficiency Virus]</p><p>[https://www.vetstream.com/felis/Content/Bug/bug60014.asp Feline Leukemia Virus]</p>}} |
| − | *Fragile, enveloped RNA viruses with roughly spherical spike proteins
| |
| − | *Genome has 3 genes:
| |
| − | **''gag'': group-specific antigen coding gene, encodes capsid proteins
| |
| − | **''pol'': encodes reverse transcriptase (RT) and integrase
| |
| − | **''env'': encodes envelope spikes, and can be used in diagnosis and subunit vaccines
| |
| − | *Both ends of genome show a promoter (LTR: long terminal repeat)
| |
| − | | |
| − | ==Antigenicity==
| |
| − | *Group-specific antigens (gag's) are shared by all isolates of each virus
| |
| − | **This can be exploited by diagnostic tests
| |
| − | *Lentiviruses show variation by mutation, making vaccination difficult
| |
| | | | |
| − | ==Virulence and Pathogenesis==
| |
| − | *Replication involves integrating into the host cell genome:
| |
| − | **'''Uncoating''' to release RNA and RT
| |
| − | **+RNA '''transcribed''' to -DNA by RT
| |
| − | **-DNA becomes circular dsDNA and is '''integrated''' into host chromosome by integrase
| |
| − | **DNA '''codes''' for viral proteins using cellular organelles and enzymes
| |
| − | **Because of this technique, virus replication is much '''slower''', and retroviruses can remain '''latent'''
| |
| − | *Tumor production takes 2 forms:
| |
| − | **Viruses can carry oncogenes within their genome --> tumor production occurs quickly
| |
| − | **Insertion of the viral LTR switches on proto-oncogenes in the host cell genome --> tumor production can take years
| |
| | | | |
| | | | |
| − | [[Category:Viruses]][[Category:To_Do_-_Viruses]] | + | [[Category:Viral Organisms]] |
| | + | [[Category:To_Do_-_Clinical/Viruses]] |