HTLV-1 orf-I is linked to immune evasion, viral replication and persistence. Examining the orf-I sequence of 160 HTLV-1-infected individuals; we found polymorphism of orf-I that alters the relative amounts of p12 and its cleavage product p8. Three groups were identified on the basis of p12 and p8 expression: predominantly p12, predominantly p8 and balanced expression of p12 and p8. We found a s...

Transient expression assays have shown that the varicella-zoster virus (VZV) open-reading frame (ORF) 29 gene product can act as a modulator of VZV gene expression. The ORF 29 protein alone does not appear to have any effect on transcription; however, in its presence, changes in the level of reporter gene activity mediated by the VZV immediate early (IE) 62 major transactivator are seen. Increa...

The human T-cell lymphotropic virus type 1 (HTLV-1) is a retrovirus associated with both proliferative and inflammatory disorders. This virus causes a persistent infection, mainly in CD4+ T lymphocyte. The ability to persist in the host is associated with the virus capacity to evade the immune response and to induce infected T-cell proliferation, once the HTLV-1 maintains the infection mainly b...

Following orf virus reinfection in sheep, CD8+ T cells were recruited to the lesion site in the skin during the period of viral replication and appeared in increased numbers in afferent lymph draining the infection site. A proportion of the CD8+ T cells were activated, particularly in the skin, as determined by their expression of the cytolytic cell-associated serine protease, BLT-esterase. Thi...

The nucleotide sequence of the genomic RNA of narcissus mosaic virus (NMV) was deduced from a set of cDNA clones and by direct sequencing of RNA. The genome, with a length of 6955 nucleotides [excluding the 3'poly(A) tail], contains six open reading frames (ORFs) with the capacity to code for polypeptides of more than 10K, with Mr values of 186284, 25845, 13998, 11059, 26097 and 10519. The firs...

The large chlorella virus PBCV-1, which contains double-stranded DNA (dsDNA), encodes a 94-codon open reading frame (ORF) that contains a motif resembling the signature sequence of the pore domain of potassium channel proteins. Phylogenetic analyses of the encoded protein, Kcv, indicate a previously unidentified type of potassium channel. The messenger RNA encoded by the ORF leads to functional...

Langerhans cells (LCs) are suspected to be initial targets for HIV after sexual exposure (by becoming infected or by capturing virus). Here, productive R5 HIV infection of LC ex vivo and LC-mediated transmission of virus to CD4+ T cells were both found to depend on CCR5. By contrast, infection of monocyte-derived dendritic cells and transfer of infection from monocyte-derived dendritic cells to...

DNA extracts from white spot syndrome virus (WSSV) that had infected post-larvae and juveniles of cultured shrimp, wild shrimp and crabs, which had been collected from different hatcheries and farms located along both the east and west coasts of India, revealed considerable variation in several previously identified WSSV DNA repeat regions. These include the 54 bp repeat in ORF 94, the 69 bp re...

Orf virus, a member of the poxvirus family, produces a pustular dermatitis in sheep, goats, and humans. The lesions induced after infection with orf virus show extensive proliferation of vascular endothelial cells, dilation of blood vessels and dermal swelling. An explanation for the nature of these lesions may lie in the discovery that orf virus encodes an apparent homolog of the mammalian vas...

During plaque purification of Spodoptera littoralis nucleopolyhedrovirus in S. littoralis Sl52 cell culture, a deletion mutant virus was isolated. Analysis of the biological properties of this mutant virus revealed an absence of per os infectivity of the occluded virus. Infectivity by injection of the non-occluded (budded) virus is not different between the wild-type and the deleted virus. Rest...