Disease relevance of Genes, pX

• This concept was further supported by the finding that the HTLV-1 trans-activator, the tax gene product, caused trans-activation of the PTHrP gene promoter linked to the CAT gene [1].
• Syngeneic rat cells selectively expressing gag, env, or pX gene coded Ag were prepared by infection of recombinant vaccinia viruses [2].
• Using transient cotransfection assays, we demonstrate that introduction of the tax gene of either HTLV-I or HTLV-II is sufficient to activate GM-CSF promoter constructs in an unstimulated T-cell line [3].
• Brain tumours and lymphomas in transgenic mice that carry HTLV-I LTR/c-myc and Ig/tax genes [4].
• Anomalous behavior of bacteriophage lambda polypeptides in polyacrylamide gels: resolution, identification, and control of the lambda rex gene product [5].

High impact information on Genes, pX

• We examined the effect of the human T lymphotropic virus type 1 (HTLV-I) Tax gene product on the human transforming growth factor beta 1 (TGF-beta 1) promoter [6].
• The ligand (muOX40L) is a type II membrane protein with significant identity to human gp34 (gp34), a protein whose expression on HTLV-1-infected human leukemic T cells is regulated by the tax gene [7].
• However, in either EL-4 (T) cells or S194 cells, both lower-affinity sites can be significantly induced by the tax gene product of human T-cell leukemia virus type I, showing that NF-kappa B activity can be modulated even in a B-cell line that constitutively expresses this factor [8].
• To explore whether there is genetic variation in HTLV-I tax that can escape CTL recognition during the development of ATL, the HTLV-I tax gene was sequenced in 55 patients with ATL, 61 patients with HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP), and 62 healthy carriers, and it was correlated with the presence of HLA-A*02 [9].
• The human T-lymphotropic virus type I tax gene can cooperate with the ras oncogene to induce neoplastic transformation of cells [10].

Chemical compound and disease context of Genes, pX

• The human T-cell leukemia virus type I (HTLV-I) long terminal repeat (LTR) is inducible both by the retroviral tax gene product and by cyclic AMP in the murine thymoma S49 cell line [11].
• The rex genes of lambda prophage modify ultraviolet light and N-methyl-N-nitrosourea-induced responses to DNA damage in Escherichia coli [12].

Biological context of Genes, pX

• Transgenic mice were produced by constructing DNAs that express the tax gene alone under the control of either its own LTR or CD4 enhancer/promoter and by microinjecting them into C3H/HeN-fertilized ova [13].
• A sequence homology between the pX genes of HTLV-I/II and the murine IL-3 gene [14].
• Using the linkage disequilibrium approach, we refined the critical region to a specific genomic interval of about 100 Kb which contains only the loricrin (LOR) gene [15].
• An open reading frame was also identified on the minus DNA strand situated between the env and rex/tax genes which exhibits 0.1-6.9% nucleotide sequence variation among HTLV1 strains [16].
• These results suggested that the tax gene in the HTLV-I genome might be a key molecule involved in cell proliferation and CD25 expression [17].

Anatomical context of Genes, pX

• To investigate the pathogenesis of pX gene in lymphoid tissues, we established a series of novel transgenic rats carrying the pX gene under the control of a rat lymphocyte-specific protein tyrosine kinase (p56lck) proximal promoter [18].
• The tax gene of human T-lymphotropic virus-I (HTLV-I) immortalizes CD4-positive lymphocytes, induces IFN-gamma, and has been detected in patients with classical CTCL who are seronegative for HTLV-I [19].

Gene context of Genes, pX

• These results suggest that the HTLV-I tax gene may transactivate the IL-8 gene through the kappa B site in HTLV-I-infected cells and that constitutive expression of the IL-8 gene may play a role in HTLV-I-associated pathogenesis [20].
• Characterization of the loricrin (LOR) gene as a positional candidate for the PSORS4 psoriasis susceptibility locus [15].
• trans activation of granulocyte-macrophage colony-stimulating factor and the interleukin-2 receptor in transgenic mice carrying the human T-lymphotropic virus type 1 tax gene [21].
• Furthermore, the tax gene strongly transactivated IL-6 gene promoter activity assayed by CAT assay [22].
• These in vivo findings are consistent with other reports which have demonstrated in vitro cis-regulatory elements within the 5'-flanking regions of the genes for GM-CSF and the IL-2 receptor which are responsive to trans activation by the tax gene [21].

Analytical, diagnostic and therapeutic context of Genes, pX

• The location of the pX gene products in human T-cell leukemia virus type 1-producing cells, MT-2 and HUT 102, was studied by immunoelectron microscopy using the direct and indirect peroxidase-labeled antibody methods [23].
• HGC/MT2 (Cl-1) and HGC/MT2 (Cl-2) cells were positive for HTLV-I gag proteins (p19 and p24) and pX gene products, p40x, as demonstrated by immunohistochemistry and immunoblotting analysis, contained HTLV-I provirus DNA, and consistently produced type C virus particles [24].
• When serially diluted DNA of MT-2 cells were amplified by 35 cycles of PCR, the detection limit of the pX gene by using the primer pairs was DNA from about 1.5 MT-2 cells [25].

References