Loading...
Viral Core Proteins: Proteins found mainly in icosahedral DNA and RNA viruses. They consist of proteins directly associated with the nucleic acid inside the NUCLEOCAPSID.Adenoviruses, Human: Species of the genus MASTADENOVIRUS, causing a wide range of diseases in humans. Infections are mostly asymptomatic, but can be associated with diseases of the respiratory, ocular, and gastrointestinal systems. Serotypes (named with Arabic numbers) have been grouped into species designated Human adenovirus A-F.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 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.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.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).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).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.Oncogene Proteins v-raf: A family of transforming proteins isolated from retroviruses such as MOUSE SARCOMA VIRUSES. They are viral-derived members of the raf-kinase family of serine-theonine kinases.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.Oncogene Protein v-crk: A signal transducing adaptor protein that is encoded by the crk ONCOGENE from TYPE C AVIAN RETROVIRUSES. It contains SRC HOMOLOGY DOMAINS and is closely related to its cellular homolog, PROTO-ONCOGENE PROTEIN C-CRK.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: An oncoprotein from the Cas NS-1 murine retrovirus that induces pre- B-CELL LYMPHOMA and MYELOID LEUKEMIAS. v-cbl protein is a tyrosine-phosphorylated, truncated form of its cellular homologue, PROTO-ONCOGENE PROTEIN C-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.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).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 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.Oncogene Proteins, Viral: Products of viral oncogenes, most commonly retroviral oncogenes. They usually have transforming and often protein kinase activities.Oncogene Proteins, Fusion: The GENETIC TRANSLATION products of the fusion between an ONCOGENE and another gene. The latter may be of viral or cellular origin.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 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.Cell Transformation, Neoplastic: Cell changes manifested by escape from control mechanisms, increased growth potential, alterations in the cell surface, karyotypic abnormalities, morphological and biochemical deviations from the norm, and other attributes conferring the ability to invade, metastasize, and kill.Genes, mos: Retrovirus-associated DNA sequences (mos) originally isolated from the Moloney murine sarcoma virus (Mo-MSV). The proto-oncogene mos (c-mos) codes for a protein which is a member of the serine kinase family. There is no evidence as yet that human c-mos can become transformed or has a role in human cancer. However, in mice, activation can occur when the retrovirus-like intracisternal A-particle inserts itself near the c-mos sequence. The human c-mos gene is located at 8q22 on the long arm of chromosome 8.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.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.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.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.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.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.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.Gene Expression Regulation, Neoplastic: Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action in neoplastic tissue.Cell Line: Established cell cultures that have the potential to propagate indefinitely.Retroviridae Proteins, Oncogenic: Retroviral proteins that have the ability to transform cells. They can induce sarcomas, leukemias, lymphomas, and mammary carcinomas. Not all retroviral proteins are oncogenic.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.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.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.Cell Line, Transformed: Eukaryotic cell line obtained in a quiescent or stationary phase which undergoes conversion to a state of unregulated growth in culture, resembling an in vitro tumor. It occurs spontaneously or through interaction with viruses, oncogenes, radiation, or drugs/chemicals.Amino Acid Sequence: The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.Cell Line, Tumor: A cell line derived from cultured tumor cells.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.Mutation: Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.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.Genes, erbB-2: The erbB-2 gene is a proto-oncogene that codes for the erbB-2 receptor (RECEPTOR, ERBB-2), a protein with structural features similar to the epidermal growth factor receptor. Its name originates from the viral oncogene homolog (v-erbB) which is a truncated form of the chicken erbB gene found in the avian erythroblastosis virus. Overexpression and amplification of the gene is associated with a significant number of adenocarcinomas. The human c-erbB-2 gene is located at 17q21.2.ras Proteins: Small, monomeric GTP-binding proteins encoded by ras genes (GENES, RAS). The protooncogene-derived protein, PROTO-ONCOGENE PROTEIN P21(RAS), plays a role in normal cellular growth, differentiation and development. The oncogene-derived protein (ONCOGENE PROTEIN P21(RAS)) can play a role in aberrant cellular regulation during neoplastic cell transformation (CELL TRANSFORMATION, NEOPLASTIC). This enzyme was formerly listed as EC 3.6.1.47.Transcription, Genetic: The biosynthesis of RNA carried out on a template of DNA. The biosynthesis of DNA from an RNA template is called REVERSE TRANSCRIPTION.Cell Division: The fission of a CELL. It includes CYTOKINESIS, when the CYTOPLASM of a cell is divided, and CELL NUCLEUS DIVISION.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: Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control (induction or repression) of gene action at the level of transcription or translation.DNA, Neoplasm: DNA present in neoplastic tissue.Mice, Transgenic: Laboratory mice that have been produced from a genetically manipulated EGG or EMBRYO, MAMMALIAN.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.Receptor, erbB-2: A cell surface protein-tyrosine kinase receptor that is overexpressed in a variety of ADENOCARCINOMAS. It has extensive homology to and heterodimerizes with the EGF RECEPTOR, the ERBB-3 RECEPTOR, and the ERBB-4 RECEPTOR. Activation of the erbB-2 receptor occurs through heterodimer formation with a ligand-bound erbB receptor family member.Translocation, Genetic: A type of chromosome aberration characterized by CHROMOSOME BREAKAGE and transfer of the broken-off portion to another location, often to a different chromosome.Mice, Nude: Mutant mice homozygous for the recessive gene "nude" which fail to develop a thymus. They are useful in tumor studies and studies on immune responses.DNA-Binding Proteins: Proteins which bind to DNA. The family includes proteins which bind to both double- and single-stranded DNA and also includes specific DNA binding proteins in serum which can be used as markers for malignant diseases.Cells, Cultured: Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.Fibroblasts: Connective tissue cells which secrete an extracellular matrix rich in collagen and other macromolecules.Transcription Factors: Endogenous substances, usually proteins, which are effective in the initiation, stimulation, or termination of the genetic transcription process.Nuclear Proteins: Proteins found in the nucleus of a cell. Do not confuse with NUCLEOPROTEINS which are proteins conjugated with nucleic acids, that are not necessarily present in the nucleus.Protein-Tyrosine Kinases: Protein kinases that catalyze the PHOSPHORYLATION of TYROSINE residues in proteins with ATP or other nucleotides as phosphate donors.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.Cell Proliferation: All of the processes involved in increasing CELL NUMBER including CELL DIVISION.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).