Genes, vpu
DNA sequences that form the coding region for the HIV-1 regulatory protein vpu (viral protein U) that greatly increases the export of virus particles from infected cells. The vpu genes are not present in HIV-2 or SIMIAN IMMUNODEFICIENCY VIRUS.
Viral Regulatory and Accessory Proteins
A broad category of viral proteins that play indirect roles in the biological processes and activities of viruses. Included here are proteins that either regulate the expression of viral genes or are involved in modifying host cell functions. Many of the proteins in this category serve multiple functions.
GPI-Linked Proteins
A subclass of lipid-linked proteins that contain a GLYCOSYLPHOSPHATIDYLINOSITOL LINKAGE which holds them to the CELL MEMBRANE.
Virus Release
Release of a virus from the host cell following VIRUS ASSEMBLY and maturation. Egress can occur by host cell lysis, EXOCYTOSIS, or budding through the plasma membrane.
HIV-1
beta-Transducin Repeat-Containing Proteins
A family of F-box domain proteins that contain sequences that are homologous to the beta subunit of transducin (BETA-TRANSDUCIN). They play an important role in the protein degradation pathway by becoming components of SKP CULLIN F-BOX PROTEIN LIGASES, which selectively act on a subset of proteins including beta-catenin and IkappaBbeta.
Antigens, CD4
55-kDa antigens found on HELPER-INDUCER T-LYMPHOCYTES and on a variety of other immune cell types. CD4 antigens are members of the immunoglobulin supergene family and are implicated as associative recognition elements in MAJOR HISTOCOMPATIBILITY COMPLEX class II-restricted immune responses. On T-lymphocytes they define the helper/inducer subset. CD4 antigens also serve as INTERLEUKIN-15 receptors and bind to the HIV receptors, binding directly to the HIV ENVELOPE PROTEIN GP120.
Antigens, CD
Differentiation antigens residing on mammalian leukocytes. CD stands for cluster of differentiation, which refers to groups of monoclonal antibodies that show similar reactivity with certain subpopulations of antigens of a particular lineage or differentiation stage. The subpopulations of antigens are also known by the same CD designation.
Macaca nemestrina
Reassortant Viruses
Gene Products, env
Retroviral proteins, often glycosylated, coded by the envelope (env) gene. They are usually synthesized as protein precursors (POLYPROTEINS) and later cleaved into the final viral envelope glycoproteins by a viral protease.
Virion
Leukemia Virus, Gibbon Ape
HeLa Cells
The first continuously cultured human malignant CELL LINE, derived from the cervical carcinoma of Henrietta Lacks. These cells are used for VIRUS CULTIVATION and antitumor drug screening assays.
Molecular Sequence Data
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
Simian immunodeficiency virus
Species of the genus LENTIVIRUS, subgenus primate immunodeficiency viruses (IMMUNODEFICIENCY VIRUSES, PRIMATE), that induces acquired immunodeficiency syndrome in monkeys and apes (SAIDS). The genetic organization of SIV is virtually identical to HIV.
Cercopithecus
A genus of Old World monkeys found in Africa although some species have been introduced into the West Indies. This genus is composed of at least twenty species: C. AETHIOPS, C. ascanius, C. campbelli, C. cephus, C. denti, C. diana, C. dryas, C. erythrogaster, C. erythrotis, C. hamlyni, C. lhoesti, C. mitis, C. mona, C. neglectus, C. nictitans, C. petaurista, C. pogonias, C. preussi, C. salongo, and C. wolfi.
Amino Acid Sequence
Gene Products, nef
Products of the retroviral NEF GENE. They play a role as accessory proteins that influence the rate of viral infectivity and the destruction of the host immune system. nef gene products were originally found as factors that trans-suppress viral replication and function as negative regulators of transcription. nef stands for negative factor.
Rimantadine
Protein Interaction Domains and Motifs
Lentiviruses, Primate
A subgenus of LENTIVIRUS comprising viruses that produce immunodeficiencies in primates, including humans.
Virus Replication
Genes, vpr
DNA sequences that form the coding region for a trans-activator protein that specifies rapid growth in human immunodeficiency virus (HIV). vpr is short for viral protein R, where R is undefined.
Cell Membrane
The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.
Down-Regulation
Gene Expression Regulation, Viral
Gorilla gorilla
This single species of Gorilla, which is a member of the HOMINIDAE family, is the largest and most powerful of the PRIMATES. It is distributed in isolated scattered populations throughout forests of equatorial Africa.
Protein Structure, Tertiary
The level of protein structure in which combinations of secondary protein structures (alpha helices, beta sheets, loop regions, and motifs) pack together to form folded shapes called domains. Disulfide bridges between cysteines in two different parts of the polypeptide chain along with other interactions between the chains play a role in the formation and stabilization of tertiary structure. Small proteins usually consist of only one domain but larger proteins may contain a number of domains connected by segments of polypeptide chain which lack regular secondary structure.
Genes, env
Simian Acquired Immunodeficiency Syndrome
Acquired defect of cellular immunity that occurs naturally in macaques infected with SRV serotypes, experimentally in monkeys inoculated with SRV or MASON-PFIZER MONKEY VIRUS; (MPMV), or in monkeys infected with SIMIAN IMMUNODEFICIENCY VIRUS.
Protein Transport
vpr Gene Products, Human Immunodeficiency Virus
Casein Kinase II
A ubiquitous casein kinase that is comprised of two distinct catalytic subunits and dimeric regulatory subunit. Casein kinase II has been shown to phosphorylate a large number of substrates, many of which are proteins involved in the regulation of gene expression.
HIV Infections
Includes the spectrum of human immunodeficiency virus infections that range from asymptomatic seropositivity, thru AIDS-related complex (ARC), to acquired immunodeficiency syndrome (AIDS).
HEK293 Cells
A cell line generated from human embryonic kidney cells that were transformed with human adenovirus type 5.
Gene Products, vpr
Trans-acting proteins which accelerate retroviral virus replication. The vpr proteins act in trans to increase the levels of specified proteins. vpr is short for viral protein R, where R is undefined.
Genes, vif
Cytoplasm
Subtilisin
Recombinant Fusion Proteins
Protein Binding
The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.
Endoplasmic Reticulum
A system of cisternae in the CYTOPLASM of many cells. In places the endoplasmic reticulum is continuous with the plasma membrane (CELL MEMBRANE) or outer membrane of the nuclear envelope. If the outer surfaces of the endoplasmic reticulum membranes are coated with ribosomes, the endoplasmic reticulum is said to be rough-surfaced (ENDOPLASMIC RETICULUM, ROUGH); otherwise it is said to be smooth-surfaced (ENDOPLASMIC RETICULUM, SMOOTH). (King & Stansfield, A Dictionary of Genetics, 4th ed)
Gene Products, vif
Retrovirally encoded accessary proteins that play an essential role VIRUS REPLICATION. They are found in the cytoplasm of host cells and associate with a variety of host cell proteins. Vif stands for "virion infectivity factor".
Ion Channels
Genes, tat
DNA sequences that form the coding region for the protein responsible for trans-activation of transcription (tat) in human immunodeficiency virus (HIV).
vif Gene Products, Human Immunodeficiency Virus
trans-Golgi Network
A network of membrane compartments, located at the cytoplasmic side of the GOLGI APPARATUS, where proteins and lipids are sorted for transport to various locations in the cell or cell membrane.
Pan troglodytes
Virus Assembly
Genes, rev
Potassium Channels, Tandem Pore Domain
Lipid Bilayers
Base Sequence
Endoplasmic Reticulum-Associated Degradation
A degradation process whereby incorrectly folded proteins are selectively transported out of the ENDOPLASMIC RETICULUM and into the CYTOSOL. The misfolded proteins are subsequently ubiquitinated and degraded by the PROTEASOME.
Genes, nef
DNA sequences that form the coding region for a protein that down-regulates the expression of human immunodeficiency virus (HIV). nef is short for negative factor.
Dichlororibofuranosylbenzimidazole
Gene Products, gag
Proteins coded by the retroviral gag gene. The products are usually synthesized as protein precursors or POLYPROTEINS, which are then cleaved by viral proteases to yield the final products. Many of the final products are associated with the nucleoprotein core of the virion. gag is short for group-specific antigen.
Radioimmunoprecipitation Assay
Sensitive assay using radiolabeled ANTIGENS to detect specific ANTIBODIES in SERUM. The antigens are allowed to react with the serum and then precipitated using a special reagent such as PROTEIN A sepharose beads. The bound radiolabeled immunoprecipitate is then commonly analyzed by gel electrophoresis.
Host-Pathogen Interactions
Macaca mulatta
Protein Structure, Secondary
Sequence Alignment
The arrangement of two or more amino acid or base sequences from an organism or organisms in such a way as to align areas of the sequences sharing common properties. The degree of relatedness or homology between the sequences is predicted computationally or statistically based on weights assigned to the elements aligned between the sequences. This in turn can serve as a potential indicator of the genetic relatedness between the organisms.
Jurkat Cells
A CELL LINE derived from human T-CELL LEUKEMIA and used to determine the mechanism of differential susceptibility to anti-cancer drugs and radiation.
rev Gene Products, Human Immunodeficiency Virus
gag Gene Products, Human Immunodeficiency Virus
Amino Acid Substitution
The naturally occurring or experimentally induced replacement of one or more AMINO ACIDS in a protein with another. If a functionally equivalent amino acid is substituted, the protein may retain wild-type activity. Substitution may also diminish, enhance, or eliminate protein function. Experimentally induced substitution is often used to study enzyme activities and binding site properties.
CD4-Positive T-Lymphocytes
A critical subpopulation of T-lymphocytes involved in the induction of most immunological functions. The HIV virus has selective tropism for the T4 cell which expresses the CD4 phenotypic marker, a receptor for HIV. In fact, the key element in the profound immunosuppression seen in HIV infection is the depletion of this subset of T-lymphocytes.
Endosomes
Cytoplasmic vesicles formed when COATED VESICLES shed their CLATHRIN coat. Endosomes internalize macromolecules bound by receptors on the cell surface.
HIV Core Protein p24
A major core protein of the human immunodeficiency virus encoded by the HIV gag gene. HIV-seropositive individuals mount a significant immune response to p24 and thus detection of antibodies to p24 is one basis for determining HIV infection by ELISA and Western blot assays. The protein is also being investigated as a potential HIV immunogen in vaccines.
Genes, gag
Transfection
env Gene Products, Human Immunodeficiency Virus
HIV-2
An HIV species related to HIV-1 but carrying different antigenic components and with differing nucleic acid composition. It shares serologic reactivity and sequence homology with the simian Lentivirus SIMIAN IMMUNODEFICIENCY VIRUS and infects only T4-lymphocytes expressing the CD4 phenotypic marker.
Viral Envelope Proteins
Layers of protein which surround the capsid in animal viruses with tubular nucleocapsids. The envelope consists of an inner layer of lipids and virus specified proteins also called membrane or matrix proteins. The outer layer consists of one or more types of morphological subunits called peplomers which project from the viral envelope; this layer always consists of glycoproteins.
Proviruses
Duplex DNA sequences in eukaryotic chromosomes, corresponding to the genome of a virus, that are transmitted from one cell generation to the next without causing lysis of the host. Proviruses are often associated with neoplastic cell transformation and are key features of retrovirus biology.
Cloning, Molecular
Retroviridae Proteins
HIV
Human immunodeficiency virus. A non-taxonomic and historical term referring to any of two species, specifically HIV-1 and/or HIV-2. Prior to 1986, this was called human T-lymphotropic virus type III/lymphadenopathy-associated virus (HTLV-III/LAV). From 1986-1990, it was an official species called HIV. Since 1991, HIV was no longer considered an official species name; the two species were designated HIV-1 and HIV-2.
Ebolavirus
A genus in the family FILOVIRIDAE consisting of several distinct species of Ebolavirus, each containing separate strains. These viruses cause outbreaks of a contagious, hemorrhagic disease (HEMORRHAGIC FEVER, EBOLA) in humans, usually with high mortality.
Primaquine
An aminoquinoline that is given by mouth to produce a radical cure and prevent relapse of vivax and ovale malarias following treatment with a blood schizontocide. It has also been used to prevent transmission of falciparum malaria by those returning to areas where there is a potential for re-introduction of malaria. Adverse effects include anemias and GI disturbances. (From Martindale, The Extra Pharmacopeia, 30th ed, p404)
Micelles
Particles consisting of aggregates of molecules held loosely together by secondary bonds. The surface of micelles are usually comprised of amphiphatic compounds that are oriented in a way that minimizes the energy of interaction between the micelle and its environment. Liquids that contain large numbers of suspended micelles are referred to as EMULSIONS.
CD4 Lymphocyte Count
The number of CD4-POSITIVE T-LYMPHOCYTES per unit volume of BLOOD. Determination requires the use of a fluorescence-activated flow cytometer.
Mutation
Viral Load
The quantity of measurable virus in a body fluid. Change in viral load, measured in plasma, is sometimes used as a SURROGATE MARKER in disease progression.
HIV Envelope Protein gp120
External envelope protein of the human immunodeficiency virus which is encoded by the HIV env gene. It has a molecular weight of 120 kDa and contains numerous glycosylation sites. Gp120 binds to cells expressing CD4 cell-surface antigens, most notably T4-lymphocytes and monocytes/macrophages. Gp120 has been shown to interfere with the normal function of CD4 and is at least partly responsible for the cytopathic effect of HIV.
Immunoprecipitation
Brefeldin A
Superinfection
A frequent complication of drug therapy for microbial infection. It may result from opportunistic colonization following immunosuppression by the primary pathogen and can be influenced by the time interval between infections, microbial physiology, or host resistance. Experimental challenge and in vitro models are sometimes used in virulence and infectivity studies.
Acquired Immunodeficiency Syndrome
An acquired defect of cellular immunity associated with infection by the human immunodeficiency virus (HIV), a CD4-positive T-lymphocyte count under 200 cells/microliter or less than 14% of total lymphocytes, and increased susceptibility to opportunistic infections and malignant neoplasms. Clinical manifestations also include emaciation (wasting) and dementia. These elements reflect criteria for AIDS as defined by the CDC in 1993.
Interferons
Proteins secreted by vertebrate cells in response to a wide variety of inducers. They confer resistance against many different viruses, inhibit proliferation of normal and malignant cells, impede multiplication of intracellular parasites, enhance macrophage and granulocyte phagocytosis, augment natural killer cell activity, and show several other immunomodulatory functions.
Green Fluorescent Proteins
Leukocytes, Mononuclear
Species Specificity
The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.
Cercopithecus aethiops
A species of CERCOPITHECUS containing three subspecies: C. tantalus, C. pygerythrus, and C. sabeus. They are found in the forests and savannah of Africa. The African green monkey (C. pygerythrus) is the natural host of SIMIAN IMMUNODEFICIENCY VIRUS and is used in AIDS research.
Hexosaminidases
Enzymes that catalyze the hydrolysis of N-acylhexosamine residues in N-acylhexosamides. Hexosaminidases also act on GLUCOSIDES; GALACTOSIDES; and several OLIGOSACCHARIDES.
Endocytosis
Cellular uptake of extracellular materials within membrane-limited vacuoles or microvesicles. ENDOSOMES play a central role in endocytosis.
Models, Molecular
Nuclear Magnetic Resonance, Biomolecular
T-Lymphocytes
Lymphocytes responsible for cell-mediated immunity. Two types have been identified - cytotoxic (T-LYMPHOCYTES, CYTOTOXIC) and helper T-lymphocytes (T-LYMPHOCYTES, HELPER-INDUCER). They are formed when lymphocytes circulate through the THYMUS GLAND and differentiate to thymocytes. When exposed to an antigen, they divide rapidly and produce large numbers of new T cells sensitized to that antigen.