A5008050382- HIV Research and Treatment
- HIV/AIDS drug development and treatment
- Monoclonal and Polyclonal Antibodies Research
- Virus-based gene therapy research
- Bacteriophages and microbial interactions
- RNA Interference and Gene Delivery
- Mosquito-borne diseases and control
- RNA Research and Splicing
- Tuberculosis Research and Epidemiology
- Lipid Membrane Structure and Behavior
- Escherichia coli research studies
- Protein Structure and Dynamics
- Immune Cell Function and Interaction
- RNA and protein synthesis mechanisms
- Crystallization and Solubility Studies
- Cellular Mechanics and Interactions
- CRISPR and Genetic Engineering
- Glycosylation and Glycoproteins Research
- SARS-CoV-2 and COVID-19 Research
- Viral Infectious Diseases and Gene Expression in Insects
- X-ray Diffraction in Crystallography
- Signaling Pathways in Disease
- Force Microscopy Techniques and Applications
- Animal Virus Infections Studies
- T-cell and Retrovirus Studies
Oregon Health & Science University
2016-2025
University of British Columbia
2023
Boston Children's Hospital
2023
Harvard University
2023
University of Victoria
2023
Vollum Institute
2000-2012
Bipar
1997
Purdue University West Lafayette
1997
Massachusetts Institute of Technology
1982-1989
Whitehead Institute for Biomedical Research
1985-1987
ABSTRACT Previous studies have shown that in addition to its function specific RNA encapsidation, the human immunodeficiency virus type 1 (HIV-1) nucleocapsid (NC) is required for efficient particle assembly. However, mechanism by which NC facilitates assembly process not clearly established. Formally, could act constraining Pr55 gag polyprotein into an assembly-competent conformation or masking residues block process. Alternatively, capacity of bind make interprotein contacts might affect...
We studied the effects of gag mutations on human immunodeficiency virus type 1 (HIV-1) assembly, processing, and infectivity by using a replication-defective HIV expression system. mutants were screened for transduction selectable marker examined assembly monitoring particle release from transfected cells. Gag protein processing reverse transcriptase activities mutant particles also assayed. Surprisingly, most assembled processed. The two exceptions to this rule myristylation-minus mutant,...
The human immunodeficiency virus type 1 (HIV-1) matrix (MA) protein targets HIV-1 precursor Gag (PrGag) proteins to assembly sites at plasma membrane (PM) that are enriched in cholesterol and phosphatidylinositol-(4,5)-bisphosphate [PI(4,5)P(2)]. MA is myristoylated, which enhances binding, specifically binds PI(4,5)P(2) through headgroup 2' acyl chain contacts. also nucleic acids, although the significance of this association with regard viral life cycle unclear. We have devised a novel...
We have analyzed the roles of Gag protein nucleocapsid (NC) domains in packaging or encapsidation retroviral RNAs into virus particles. found that mutation both zinc finger motifs human immunodeficiency (HIV) NC domain reduced but did not eliminate HIV viral RNA. However, mutations also resulted a three- to fourfold reduction specificity RNA encapsidation, as determined by comparison virus-associated genomic and spliced levels. As complementary approach, we replaced Moloney murine leukemia...
Abstract Zika virus (ZIKV), an arbovirus of global concern, remodels intracellular membranes to form replication sites. How ZIKV dysregulates lipid networks allow this, and consequences for disease, is poorly understood. Here, we perform comprehensive lipidomics create a network map during infection. We find that significantly alters host composition, with the most striking changes seen within subclasses sphingolipids. Ectopic expression NS4B protein results in similar changes, demonstrating...
We constructed a human immunodeficiency virus (HIV) matrix (MA) deletion mutant by of about 80% the HIV type 1 Gag MA domain but retaining myristylation and proteolytic processing signals. The effects this (dl.MA) on particle assembly, processing, infectivity were analyzed. Surprisingly, dl.MA still could assemble process particles, had wild-type (wt) retrovirus density, possessed wt reverse transcriptase activity. RNase protection experiments showed that particles preferentially packaged...
We have studied the process of Moloney murine leukemia virus (M-MuLV) assembly by characterization core (gag) protein mutants and analysis wild-type (wt) gag proteins produced cells in presence ionophore monensin. Our genetic studies involved examination linker insertion a Gag-beta-galactosidase (Gag-beta-gal) fusion protein, GBG2051, which is incorporated into particles when expressed wt viral proteins. Analysis indicated that amino-terminal two-thirds matrix domain essential for targeting...
We studied the expression of beta-galactosidase (beta-gal) and 15 gag-beta-gal fusion proteins in presence Moloney murine leukemia virus wild-type core (gag) proteins. Analysis indicated that retaining amino-terminal portion gag through capsid protein-coding region were incorporated into retrovirus particles. Proteins which deleted portions protein assembled virions at low efficiency, indicating importance interactions assembly. Fusion retained matrix polyprotein but lacked released...
Retrovirus expression in embryonal carcinoma (EC) cells is blocked at a postintegration stage of the viral life cycle, part because inadequate function long terminal repeat promoter this cell type. However, selection for retrovirus EC has identified mutations Moloney murine leukemia virus (M-MuLV) located tRNA primer-binding site (PBS) region which relieve cell-specific repression. We have found that exchanging M-MuLV proline PBS glutamine one recombinant permits cells. By using as backbone,...
ABSTRACT We have examined the interactions of wild-type (WT) and matrix protein-deleted (ΔMA) HIV-1 precursor Gag (PrGag) proteins in virus-producing cells using a biotin ligase-tagging approach. To do so, WT ΔMA PrGag were tagged with Escherichia coli promiscuous ligase (BirA*), expressed cells, examined. Localization patterns biotinylated overlapped, consistent observations that BirA*-tagged biotinylate neighbor are close proximity. Results indicate themselves as well trans . Previous data...
The spike glycoprotein of SARS-CoV-2 engages with human ACE 2 to facilitate infection. Here, we describe an alpaca-derived heavy chain antibody fragment (VHH), saRBD-1, that disrupts this interaction by competitively binding the protein receptor-binding domain. We further generated engineered bivalent nanobody construct a flexible linker and dimeric Fc conjugated construct. Both multivalent nanobodies blocked infection at picomolar concentrations demonstrated no loss potency against emerging...
Based on observations that HIV-1 envelope (Env) proteins the surfaces of cells have capacity to fuse with neighboring or enveloped viruses express CD4 receptors and CXCR4 co-receptors, we tested factors affect capacities lentiviral vectors pseudotyped variants infect Env-expressing cells. The process, which refer as fusion in reverse, involves binding activation cellular Env membranes lentiviruses carrying proteins. We found infection via reverse depends cell surface levels, is inhibitable...
Based on observations that HIV-1 envelope (Env) proteins the surfaces of cells have capacity to fuse with neighboring or enveloped viruses express CD4 receptors and CXCR4 co-receptors, we tested factors affect capacities lentiviral vectors pseudotyped variants infect Env-expressing cells. The process, which refer as fusion in reverse, involves binding activation cellular Env membranes lentiviruses carrying proteins. We found infection via reverse depends cell surface levels, is inhibitable...
ABSTRACT Hantaviruses are enveloped, negative-strand RNA viruses which can be lethal to humans, causing either a hemorrhagic fever with renal syndrome or hantaviral pulmonary syndrome. The viral genomes consist of three segments: the L segment encodes polymerase, M surface glycoproteins G1 and G2, S nucleocapsid (N) protein. N protein is 420- 430-residue, 50-kDa appears direct hantavirus assembly, although mechanisms oligomerization, encapsidation, budding, release poorly understood. We have...
The human immunodeficiency virus (HIV) Pr55Gag precursor proteins direct particle assembly. While Gag-Gag protein interactions which affect HIV assembly occur in the capsid (CA) domain of Pr55Gag, nucleocapsid (NC) domain, functions viral RNA encapsidation, also appears to participate In order dissect roles NC and p6 C-terminal Gag we examined effects mutations on encapsidation. our experimental system, did not appear release efficiency but deletions truncations reduced specificity genomic...
Moloney murine leukemia virus (M-MuLV) and M-MuLV-derived retroviral vectors are not expressed in early mouse embryos or embryonal carcinoma cells. mutants M-MuLV-related variants which transduce the neomycin phosphotransferase gene can, however, induce drug resistance cells with high efficiency. In this study we investigated sequences critical for expression two different cell lines, F9 PCC4. We show that synergistically acting sequence elements mediate One of these is located within U3...
HIV-1 Nef triggers down-regulation of cell-surface MHC-I by assembling a Src family kinase (SFK)-ZAP-70/Syk-PI3K cascade. Here, we report that chemical disruption the Nef-SFK interaction with small molecule inhibitor 2c blocks assembly multi-kinase complex and represses HIV-1–mediated in primary CD4 + T-cells. did not interfere PACS-2–dependent trafficking required for or AP-1 PACS-1–dependent sequestering internalized MHC-I, suggesting specifically interfered triggering down-regulation....