Oncogene Protein p55(v-myc)
Transforming protein coded by myc oncogenes. The v-myc protein has been found in several replication-defective avian retrovirus isolates which induce a broad spectrum of malignancies.
Oncogene Protein p65(gag-jun)
Transforming protein coded by jun oncogenes (GENES, JUN). This is a gag-onc fusion protein of about 65 kDa derived from avian sarcoma virus. v-jun lacks a negative regulatory domain that regulates transcription in c-jun.
Gelatinases
Serine Endopeptidases
Oncogene Proteins v-sis
Transforming proteins coded by sis oncogenes. Transformation of cells by v-sis is related to its interaction with the PDGF receptor and also its ability to alter other transcription factors.
Oncogene Protein p21(ras)
Transforming protein encoded by ras oncogenes. Point mutations in the cellular ras gene (c-ras) can also result in a mutant p21 protein that can transform mammalian cells. Oncogene protein p21(ras) has been directly implicated in human neoplasms, perhaps accounting for as much as 15-20% of all human tumors. This enzyme was formerly listed as EC 3.6.1.47.
Oncogene Protein tpr-met
The GENETIC TRANSLATION product from a GENE FUSION between a sequence from the tpr protein gene on the human CHROMOSOME 1 and the gene for PROTO-ONCOGENE PROTEINS C-MET.
Dipeptidyl-Peptidases and Tripeptidyl-Peptidases
Oncogene Protein v-maf
An oncogene protein that was originally isolated from a spontaneous musculo-aponeurotic FIBROSARCOMA in CHICKEN and shown to be the transforming gene of the avian retrovirus AS42. It is a basic leucine zipper TRANSCRIPTION FACTOR and the founding member of the MAF TRANSCRIPTION FACTORS.
Dipeptidyl Peptidase 4
A serine protease that catalyses the release of an N-terminal dipeptide. Several biologically-active peptides have been identified as dipeptidyl peptidase 4 substrates including INCRETINS; NEUROPEPTIDES; and CHEMOKINES. The protein is also found bound to ADENOSINE DEAMINASE on the T-CELL surface and is believed to play a role in T-cell activation.
Oncogene Protein gp140(v-fms)
Transforming glycoprotein coded by the fms oncogene from the Susan McDonough strain of feline sarcoma virus (SM-FeSV). The oncogene protein v-fms lacks sequences, which, in the highly homologous proto-oncogene protein c-fms (CSF-1 receptor), normally serve to regulate its tyrosine kinase activity. The missing sequences in v-fms mimic the effect of ligand and lead to constitutive cell growth. The protein gp120(v-fms) is post-translationally modified to generate gp140(v-fms).
Membrane Proteins
Antigens, Neoplasm
Oncogene Proteins v-mos
Transforming proteins coded by mos oncogenes. The v-mos proteins were originally isolated from the Moloney murine sarcoma virus (Mo-MSV).
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.
Genes, gag
Tumor Markers, Biological
Molecular products metabolized and secreted by neoplastic tissue and characterized biochemically in cells or body fluids. They are indicators of tumor stage and grade as well as useful for monitoring responses to treatment and predicting recurrence. Many chemical groups are represented including hormones, antigens, amino and nucleic acids, enzymes, polyamines, and specific cell membrane proteins and lipids.
Fibroblasts
Oncogene Proteins v-raf
Oncogene Proteins v-fos
Transforming proteins coded by fos oncogenes. These proteins have been found in the Finkel-Biskis-Jinkins (FBJ-MSV) and Finkel-Biskis-Reilly (FBR-MSV) murine sarcoma viruses which induce osteogenic sarcomas in mice. The FBJ-MSV v-fos gene encodes a p55-kDa protein and the FBR-MSV v-fos gene encodes a p75-kDa fusion protein.
Genes, jun
Retrovirus-associated DNA sequences (jun) originally isolated from the avian sarcoma virus 17 (ASV 17). The proto-oncogene jun (c-jun) codes for a nuclear protein which is involved in growth-related transcriptional control. Insertion of c-jun into ASV-17 or the constitutive expression of the c-jun protein produces tumorgenicity. The human c-jun gene is located at 1p31-32 on the short arm of chromosome 1.
Oncogene Protein v-crk
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.
Oncogene Proteins v-myb
Transforming proteins coded by myb oncogenes. Transformation of cells by v-myb in conjunction with v-ets is seen in the avian E26 leukemia virus.
Oncogene Protein v-cbl
Oncogene Proteins v-erbB
Transforming proteins encoded by erbB oncogenes from the avian erythroblastosis virus. The protein is a truncated form of the EGF receptor (RECEPTOR, EPIDERMAL GROWTH FACTOR) whose kinase domain is constitutively activated by deletion of the ligand-binding domain.
Oncogene Proteins v-abl
Transforming proteins encoded by the abl oncogenes. Oncogenic transformation of c-abl to v-abl occurs by insertional activation that results in deletions of specific N-terminal amino acids.
Oncogenes
Genes whose gain-of-function alterations lead to NEOPLASTIC CELL TRANSFORMATION. They include, for example, genes for activators or stimulators of CELL PROLIFERATION such as growth factors, growth factor receptors, protein kinases, signal transducers, nuclear phosphoproteins, and transcription factors. A prefix of "v-" before oncogene symbols indicates oncogenes captured and transmitted by RETROVIRUSES; the prefix "c-" before the gene symbol of an oncogene indicates it is the cellular homolog (PROTO-ONCOGENES) of a v-oncogene.
Growth Substances
Oncogene Proteins v-rel
Transforming proteins coded by rel oncogenes. The v-rel protein competes with rel-related proteins and probably transforms cells by acting as a dominant negative version of c-rel. This results in the induction of a broad range of leukemias and lymphomas.
Oncogene Proteins v-erbA
Transforming proteins encoded by erbA oncogenes from the avian erythroblastosis virus. They are truncated versions of c-erbA, the thyroid hormone receptor (RECEPTORS, THYROID HORMONE) that have retained both the DNA-binding and hormone-binding domains. Mutations in the hormone-binding domains abolish the transcriptional activation function. v-erbA acts as a dominant repressor of c-erbA, inducing transformation by disinhibiting proliferation.
Oncogene Proteins
Proteins coded by oncogenes. They include proteins resulting from the fusion of an oncogene and another gene (ONCOGENE PROTEINS, FUSION).
Cell Line, Tumor
A cell line derived from cultured tumor cells.
Transfection
The uptake of naked or purified DNA by CELLS, usually meaning the process as it occurs in eukaryotic cells. It is analogous to bacterial transformation (TRANSFORMATION, BACTERIAL) and both are routinely employed in GENE TRANSFER TECHNIQUES.
Neoplasms
gag Gene Products, Human Immunodeficiency Virus
Immunohistochemistry
DNA, Complementary
Alanine
Catalytic Domain
Proto-Oncogene Proteins c-jun
Cellular DNA-binding proteins encoded by the c-jun genes (GENES, JUN). They are involved in growth-related transcriptional control. There appear to be three distinct functions: dimerization (with c-fos), DNA-binding, and transcriptional activation. Oncogenic transformation can take place by constitutive expression of c-jun.
Tumor Suppressor Protein p53
Nuclear phosphoprotein encoded by the p53 gene (GENES, P53) whose normal function is to control CELL PROLIFERATION and APOPTOSIS. A mutant or absent p53 protein has been found in LEUKEMIA; OSTEOSARCOMA; LUNG CANCER; and COLORECTAL CANCER.
Oncogene Protein pp60(v-src)
A tyrosine-specific protein kinase encoded by the v-src oncogene of ROUS SARCOMA VIRUS. The transforming activity of pp60(v-src) depends on both the lack of a critical carboxy-terminal tyrosine phosphorylation site at position 527, and the attachment of pp60(v-src) to the plasma membrane which is accomplished by myristylation of its N-terminal glycine.
Neoplasm Transplantation
Experimental transplantation of neoplasms in laboratory animals for research purposes.
Oncogene Proteins, Viral
Models, Molecular
Flow Cytometry
Technique using an instrument system for making, processing, and displaying one or more measurements on individual cells obtained from a cell suspension. Cells are usually stained with one or more fluorescent dyes specific to cell components of interest, e.g., DNA, and fluorescence of each cell is measured as it rapidly transverses the excitation beam (laser or mercury arc lamp). Fluorescence provides a quantitative measure of various biochemical and biophysical properties of the cell, as well as a basis for cell sorting. Other measurable optical parameters include light absorption and light scattering, the latter being applicable to the measurement of cell size, shape, density, granularity, and stain uptake.
Cell Transformation, Neoplastic
Base Sequence
Genes, ras
Family of retrovirus-associated DNA sequences (ras) originally isolated from Harvey (H-ras, Ha-ras, rasH) and Kirsten (K-ras, Ki-ras, rasK) murine sarcoma viruses. Ras genes are widely conserved among animal species and sequences corresponding to both H-ras and K-ras genes have been detected in human, avian, murine, and non-vertebrate genomes. The closely related N-ras gene has been detected in human neuroblastoma and sarcoma cell lines. All genes of the family have a similar exon-intron structure and each encodes a p21 protein.
Oncogene Proteins, Fusion
Amino Acid Sequence
Oncogene Protein v-akt
A viral oncoprotein originally isolated from a murine T CELL LYMPHOMA infected with the acutely transforming retrovirus AKT8. v-akt protein is the viral homologue of PROTO-ONCOGENE PROTEINS C-AKT.
Bacillus Phages
Viruses whose host is Bacillus. Frequently encountered Bacillus phages include bacteriophage phi 29 and bacteriophage phi 105.
Proto-Oncogene Proteins
Products of proto-oncogenes. Normally they do not have oncogenic or transforming properties, but are involved in the regulation or differentiation of cell growth. They often have protein kinase activity.
Proto-Oncogene Proteins c-fos
Cellular DNA-binding proteins encoded by the c-fos genes (GENES, FOS). They are involved in growth-related transcriptional control. c-fos combines with c-jun (PROTO-ONCOGENE PROTEINS C-JUN) to form a c-fos/c-jun heterodimer (TRANSCRIPTION FACTOR AP-1) that binds to the TRE (TPA-responsive element) in promoters of certain genes.
Mutation
Proto-Oncogenes
Normal cellular genes homologous to viral oncogenes. The products of proto-oncogenes are important regulators of biological processes and appear to be involved in the events that serve to maintain the ordered procession through the cell cycle. Proto-oncogenes have names of the form c-onc.
Transcription Factors
DNA-Binding Proteins
Proto-Oncogene Proteins p21(ras)
Cellular proteins encoded by the H-ras, K-ras and N-ras genes. The proteins have GTPase activity and are involved in signal transduction as monomeric GTP-binding proteins. Elevated levels of p21 c-ras have been associated with neoplasia. This enzyme was formerly listed as EC 3.6.1.47.
Transcription, Genetic
Nuclear Proteins
Retroviridae Proteins, Oncogenic
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.
Retinoblastoma-Like Protein p130
A negative regulator of the CELL CYCLE that undergoes PHOSPHORYLATION by CYCLIN-DEPENDENT KINASES. RBL2 contains a conserved pocket region that binds E2F4 TRANSCRIPTION FACTOR and E2F5 TRANSCRIPTION FACTOR. RBL2 also interacts with viral ONCOPROTEINS such as POLYOMAVIRUS TUMOR ANTIGENS; ADENOVIRUS E1A PROTEINS; and PAPILLOMAVIRUS E7 PROTEINS.
HIV-1
Virus Assembly
The assembly of VIRAL STRUCTURAL PROTEINS and nucleic acid (VIRAL DNA or VIRAL RNA) to form a VIRUS PARTICLE.
Retroviridae Proteins
Proteins from the family Retroviridae. The most frequently encountered member of this family is the Rous sarcoma virus protein.
Signal Transduction
The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.
Gene Expression Regulation
Promoter Regions, Genetic
Tumor Cells, Cultured
Cells grown in vitro from neoplastic tissue. If they can be established as a TUMOR CELL LINE, they can be propagated in cell culture indefinitely.
RNA, Messenger
RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.
Gene Expression Regulation, Neoplastic
Bacteriophage PRD1
Cells, Cultured
Recombinant Fusion Proteins
JNK Mitogen-Activated Protein Kinases
A subgroup of mitogen-activated protein kinases that activate TRANSCRIPTION FACTOR AP-1 via the phosphorylation of C-JUN PROTEINS. They are components of intracellular signaling pathways that regulate CELL PROLIFERATION; APOPTOSIS; and CELL DIFFERENTIATION.
Proto-Oncogene Proteins c-myc
Cellular DNA-binding proteins encoded by the c-myc genes. They are normally involved in nucleic acid metabolism and in mediating the cellular response to growth factors. Elevated and deregulated (constitutive) expression of c-myc proteins can cause tumorigenesis.
Retinoblastoma-Like Protein p107
A negative regulator of the CELL CYCLE that undergoes PHOSPHORYLATION by CYCLIN-DEPENDENT KINASES. It contains a conserved pocket region that binds E2F4 TRANSCRIPTION FACTOR and interacts with viral ONCOPROTEINS such as POLYOMAVIRUS TUMOR ANTIGENS; ADENOVIRUS E1A PROTEINS; and PAPILLOMAVIRUS E7 PROTEINS.
Cell Transformation, Viral
An inheritable change in cells manifested by changes in cell division and growth and alterations in cell surface properties. It is induced by infection with a transforming virus.
Transcription Factor AP-1
A multiprotein complex composed of the products of c-jun and c-fos proto-oncogenes. These proteins must dimerize in order to bind to the AP-1 recognition site, also known as the TPA-responsive element (TRE). AP-1 controls both basal and inducible transcription of several genes.
Cloning, Molecular
The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.
Cell Line, Transformed
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.
Binding Sites
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.
Phosphorylation
Genes, myc
Family of retrovirus-associated DNA sequences (myc) originally isolated from an avian myelocytomatosis virus. The proto-oncogene myc (c-myc) codes for a nuclear protein which is involved in nucleic acid metabolism and in mediating the cellular response to growth factors. Truncation of the first exon, which appears to regulate c-myc expression, is crucial for tumorigenicity. The human c-myc gene is located at 8q24 on the long arm of chromosome 8.
Apoptosis
One of the mechanisms by which CELL DEATH occurs (compare with NECROSIS and AUTOPHAGOCYTOSIS). Apoptosis is the mechanism responsible for the physiological deletion of cells and appears to be intrinsically programmed. It is characterized by distinctive morphologic changes in the nucleus and cytoplasm, chromatin cleavage at regularly spaced sites, and the endonucleolytic cleavage of genomic DNA; (DNA FRAGMENTATION); at internucleosomal sites. This mode of cell death serves as a balance to mitosis in regulating the size of animal tissues and in mediating pathologic processes associated with tumor growth.
Phosphoproteins
Gene Amplification
A selective increase in the number of copies of a gene coding for a specific protein without a proportional increase in other genes. It occurs naturally via the excision of a copy of the repeating sequence from the chromosome and its extrachromosomal replication in a plasmid, or via the production of an RNA transcript of the entire repeating sequence of ribosomal RNA followed by the reverse transcription of the molecule to produce an additional copy of the original DNA sequence. Laboratory techniques have been introduced for inducing disproportional replication by unequal crossing over, uptake of DNA from lysed cells, or generation of extrachromosomal sequences from rolling circle replication.
Retroviridae
Family of RNA viruses that infects birds and mammals and encodes the enzyme reverse transcriptase. The family contains seven genera: DELTARETROVIRUS; LENTIVIRUS; RETROVIRUSES TYPE B, MAMMALIAN; ALPHARETROVIRUS; GAMMARETROVIRUS; RETROVIRUSES TYPE D; and SPUMAVIRUS. A key feature of retrovirus biology is the synthesis of a DNA copy of the genome which is integrated into cellular DNA. After integration it is sometimes not expressed but maintained in a latent state (PROVIRUSES).
3T3 Cells
Cell lines whose original growing procedure consisted being transferred (T) every 3 days and plated at 300,000 cells per plate (J Cell Biol 17:299-313, 1963). Lines have been developed using several different strains of mice. Tissues are usually fibroblasts derived from mouse embryos but other types and sources have been developed as well. The 3T3 lines are valuable in vitro host systems for oncogenic virus transformation studies, since 3T3 cells possess a high sensitivity to CONTACT INHIBITION.
Virion
DNA
A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).
Transcriptional Activation
Cell Division
Fusion Proteins, gag-pol
Blotting, Western
Virus Replication
Protein Precursors
Gene Expression
Plasmids
Extrachromosomal, usually CIRCULAR DNA molecules that are self-replicating and transferable from one organism to another. They are found in a variety of bacterial, archaeal, fungal, algal, and plant species. They are used in GENETIC ENGINEERING as CLONING VECTORS.