Human immunodeficiency virus type 1 (HIV-1) vpr inhibits the replication of tumor cell lines and peripheral blood mononuclear cells. Here it is demonstrated that expression vpr, either in context a provirus or from an independent genetic element, induces discrete cycle arrest, with cells containing 4N DNA. Low cyclin B-associated kinase activity, as well status p34cdc2 cdc25C phosphorylation, indicates cascade reactions which drives into mitosis has not been initiated. The phosphatase...

Cyclophilin A (CyPA) is incorporated into human immunodeficiency virus type 1 (HIV-1) virions via contact with the Gag polyprotein. Genetic or pharmacologic disruption of CyPA incorporation causes a quantitative reduction in virion infectivity no discernible effects on assembly endogenous reverse transcriptase activity. Instead, virion-associated accompanied by parallel, decrease initiation viral DNA synthesis after infection T cells. The CyPA-deficient not restored pseudotyping Env...

The human immunodeficiency virus type 1 (HIV-1) Gag polyprotein binds to cyclophilin A and incorporates this cellular peptidyl prolyl-isomerase into virions. Disruption of incorporation, either by gag mutations or cyclosporine A, inhibits virion infectivity, indicating that plays an essential role in the HIV-1 life cycle. Using assays for packaging virions viral replication sensitivity as well information gleaned from alignment residues encoded representative isolates, we demonstrate five...

The cellular peptidyl-prolyl isomerase cyclophilin A is incorporated into human immunodeficiency virus type 1 virions via contacts with the proline-rich domain of Gag polyprotein. Cyclosporine and nonimmunosuppressive analogs bind high affinity to A, compete for binding prevent incorporation virions; in parallel disruption virions, there a linear reduction initiation reverse transcription after infection T cell. Passage presence drug selects one two mutations, either which alters sufficient...

ABSTRACT Cell surface glycosaminoglycans (GAGs), in particular heparan sulfate (HS), have been proposed to mediate the attachment of human immunodeficiency virus type 1 (HIV-1) target cells prior entry, and both viral gp120 envelope protein virion-associated cyclophilin A (CypA) shown directly interact with HS its analogues. To determine role GAGs HIV infection, we generated HIV-susceptible derivatives CHO cell lines that either express high levels (CHO-K1) or lack (pgsA745). Using a panel...

Completion of an early step in the human immunodeficiency virus type 1 (HIV-1) life cycle requires incorporation into virions cellular peptidyl-prolyl isomerase cyclophilin A (CyPA) by Gag polyprotein. Elucidation biochemical role CyPA would be aided a detailed analysis genetic requirements for formation Gag-CyPA complex; previous experiments have demonstrated requirement critical proline and immediately preceding glycine, located within capsid domain Gag, but nothing is known about...

ABSTRACT Human immunodeficiency virus type 1 (HIV-1) Gag and the cellular protein cyclophilin A form an essential complex in virion core: virions produced by proviruses encoding mutants with decreased affinity exhibit attenuated infectivity, as do presence of competitive inhibitor cyclosporine. The A224E mutant has no effect on but renders HIV-1 replication cyclosporine resistant Jurkat T cells. In contrast, is dead H9 cells, although rescued or expression cis a that decreases A-affinity....

ABSTRACT Strategies to prime CD8 + T cells against Murine gammaherpesvirus 68 (γHV68; MHV68) latency have, date, resulted in only limited effects. While early forms of (<21 days) were significantly reduced, effects not seen at later times, indicating loss control by the primed cells. In present study, we evaluated an optimized system, consisting OTI T-cell-receptor (TCR) transgenic mice, which generate clonal specific for K b -SIINFEKL OVA, and a recombinant γHV68 that expresses OVA...

Journal Article Locations and contexts of sequences that hybridize to poly(dG-dT).(dC-dA) in mammalian ribosomal DNAs two X-linked genes Get access Douglas C. Braaten, Braaten Search for other works by this author on: Oxford Academic PubMed Google Scholar James R. Thomas, Thomas Randall D. Little, Little Kevin Dickson, Dickson Ilya Goldberg, Goldberg David Schlessinger, Schlessinger Alfredo Ciccodicola, Ciccodicola 1International Institute Genetics BiophysicsNaples 80125, Italy Michele...

CD4 T cells are important for control of infection with murine gammaherpesvirus 68 (gamma HV68), but it is not known whether function via provision help to other lymphocyte subsets, such as B and CD8 cells, or have an independent antiviral function. Moreover, under conditions natural infection, the T-cell response sufficient eliminate infection. To determine functional capacities optimal near-optimal can gamma HV68 in absence we studied effect ovalbumin (OVA)-specific on a recombinant that...

Control of virus infection is mediated in part by major histocompatibility complex (MHC) Class Ia presentation viral peptides to conventional CD8 T cells. Although important, the absolute requirement for MHC Ia–dependent cells control chronic has not been formally demonstrated. We show here that mice lacking molecules (Kb−/−xDb−/− mice) effectively γ-herpesvirus 68 (γHV68) via a robust expansion β2-microglobulin (β2-m)-dependent, but CD1d-independent, unconventional These expressed: (1)...

Mouse L-cell nucleoli were isolated from sonicated nuclei by centrifugation and extensively treated with pancreatic DNase or micrococcal nuclease to obtain "core nucleoli." Core still contained the precursors rRNA about 1% of total nuclear DNA, which remained tightly bound even after removal some chromatin proteins 2 M NaCl. The core nucleolar DNA electrophoresed in a series discrete bands, 20 200 base pairs length. Hybridization tests specific probes showed that was devoid sequences...

Mouse L-cell nucleoli were isolated from sonicated nuclei by centrifugation and extensively treated with pancreatic DNase or micrococcal nuclease to obtain "core nucleoli." Core still contained the precursors rRNA about 1% of total nuclear DNA, which remained tightly bound even after removal some chromatin proteins 2 M NaCl. The core nucleolar DNA electrophoresed in a series discrete bands, 20 200 base pairs length. Hybridization tests specific probes showed that was devoid sequences...

Herpesviruses are thought to be highly genetically stable, and their use as vaccine vectors has been proposed. However, studies of the human gammaherpesvirus, Epstein-Barr virus, have found viral isolates containing mutations in HLA class I-restricted epitopes. Using murine gammaherpesvirus 68 expressing ovalbumin (OVA), we examined stability a antigenic locus under strong CD8 T cell selection vivo. OVA-specific cells selected OVA but minimal alterations other genomic regions. Thus, response...