The major homology region of bovine leukaemia virus p24gag is required for virus infectivity in vivo.

Active human immunodeficiency virus protease is required for viral infectivity.

Retroviral proteins are synthesized as polyprotein precursors that undergo proteolytic cleavages to yield the mature viral proteins. The role of the human immunodeficiency virus (HIV) protease in the viral replication cycle was examined by use of a site-directed mutation in the protease gene. The HIV protease gene product was expressed in Escherichia coli and observed to cleave HIV gag p55 to g...

Bovine leukaemia virus and enzootic bovine leukosis.

Infection of bovines with bovine leukaemia virus (BLV) manifests itself in either of two ways: 30-70% of carriers develop persistent lymphocytosis (PL), with the viral genome integrated at a large number of different sites in the DNA of the affected B-lymphocytes, without causing any chromosomal abnormalities. Only 0,1-10% of carriers develop lymphoid tumours, which also consist of B-lymphocyte...

Bovine Leukaemia Virus onco-protein Tax antigen identification in human lymphomas tissue

Background: Bovine leukaemia virus (BLV) is the primary cause of enzootic bovine leukaemia which belongs to the HTLV/BLV group of oncogenic retroviruses including Human T-cell leukaemia virus types 1, 2, and 3 and simian T-lymphotropic virus. Due to daily consumption of milk, meat and other dairy by-products, a possible role in appearing human cancers can be assumed for BLV. Materials and Metho...

Vaccinia virus glycoprotein A34R is required for infectivity of extracellular enveloped virus.

The vaccinia virus strain Western Reserve (WR) A34R gene encodes a C-type lectin-like glycoprotein, gp22-24, that is present in the outer membrane of extracellular enveloped virus (EEV) with type II membrane topology (S.A. Duncan and G.L. Smith, J. Virol. 66:1610-1621, 1992). Here we that a WR A34R deletion mutant (WR delta A34R) released 19- to 24-fold more EEV from infected cells than did WR ...

The occurrence of bovine virus diarrhoea/muscosal disease in Iran