Dimerization: The process by which two molecules of the same chemical composition form a condensation product or polymer.Protein Multimerization: The assembly of the QUATERNARY PROTEIN STRUCTURE of multimeric proteins (MULTIPROTEIN COMPLEXES) from their composite PROTEIN SUBUNITS.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.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.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.Models, Molecular: Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.Protein Structure, Quaternary: The characteristic 3-dimensional shape and arrangement of multimeric proteins (aggregates of more than one polypeptide chain).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.Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.Protein Conformation: The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).Leucine Zippers: DNA-binding motifs formed from two alpha-helixes which intertwine for about eight turns into a coiled coil and then bifurcate to form Y shaped structures. Leucines occurring in heptad repeats end up on the same sides of the helixes and are adjacent to each other in the stem of the Y (the "zipper" region). The DNA-binding residues are located in the bifurcated region of the Y.Crystallography, X-Ray: The study of crystal structure using X-RAY DIFFRACTION techniques. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)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.Protein Structure, Secondary: The level of protein structure in which regular hydrogen-bond interactions within contiguous stretches of polypeptide chain give rise to alpha helices, beta strands (which align to form beta sheets) or other types of coils. This is the first folding level of protein conformation.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.Mutagenesis, Site-Directed: Genetically engineered MUTAGENESIS at a specific site in the DNA molecule that introduces a base substitution, or an insertion or deletion.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Recombinant Fusion Proteins: Recombinant proteins produced by the GENETIC TRANSLATION of fused genes formed by the combination of NUCLEIC ACID REGULATORY SEQUENCES of one or more genes with the protein coding sequences of one or more genes.Cell Line: Established cell cultures that have the potential to propagate indefinitely.Biopolymers: Polymers synthesized by living organisms. They play a role in the formation of macromolecular structures and are synthesized via the covalent linkage of biological molecules, especially AMINO ACIDS; NUCLEOTIDES; and CARBOHYDRATES.Sequence Homology, Amino Acid: The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.Recombinant Proteins: Proteins prepared by recombinant DNA technology.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.Cross-Linking Reagents: Reagents with two reactive groups, usually at opposite ends of the molecule, that are capable of reacting with and thereby forming bridges between side chains of amino acids in proteins; the locations of naturally reactive areas within proteins can thereby be identified; may also be used for other macromolecules, like glycoproteins, nucleic acids, or other.Transcription Factors: Endogenous substances, usually proteins, which are effective in the initiation, stimulation, or termination of the genetic transcription process.COS Cells: CELL LINES derived from the CV-1 cell line by transformation with a replication origin defective mutant of SV40 VIRUS, which codes for wild type large T antigen (ANTIGENS, POLYOMAVIRUS TRANSFORMING). They are used for transfection and cloning. (The CV-1 cell line was derived from the kidney of an adult male African green monkey (CERCOPITHECUS AETHIOPS).)Macromolecular Substances: Compounds and molecular complexes that consist of very large numbers of atoms and are generally over 500 kDa in size. In biological systems macromolecular substances usually can be visualized using ELECTRON MICROSCOPY and are distinguished from ORGANELLES by the lack of a membrane structure.Amino Acid Motifs: Commonly observed structural components of proteins formed by simple combinations of adjacent secondary structures. A commonly observed structure may be composed of a CONSERVED SEQUENCE which can be represented by a CONSENSUS SEQUENCE.Structure-Activity Relationship: The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.Disulfides: Chemical groups containing the covalent disulfide bonds -S-S-. The sulfur atoms can be bound to inorganic or organic moieties.Protein Interaction Domains and Motifs: Protein modules with conserved ligand-binding surfaces which mediate specific interaction functions in SIGNAL TRANSDUCTION PATHWAYS and the specific BINDING SITES of their cognate protein LIGANDS.Ligands: A molecule that binds to another molecule, used especially to refer to a small molecule that binds specifically to a larger molecule, e.g., an antigen binding to an antibody, a hormone or neurotransmitter binding to a receptor, or a substrate or allosteric effector binding to an enzyme. Ligands are also molecules that donate or accept a pair of electrons to form a coordinate covalent bond with the central metal atom of a coordination complex. (From Dorland, 27th ed)Cysteine: A thiol-containing non-essential amino acid that is oxidized to form CYSTINE.Ultracentrifugation: Centrifugation with a centrifuge that develops centrifugal fields of more than 100,000 times gravity. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)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).Kinetics: The rate dynamics in chemical or physical systems.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.Fluorescence Resonance Energy Transfer: A type of FLUORESCENCE SPECTROSCOPY using two FLUORESCENT DYES with overlapping emission and absorption spectra, which is used to indicate proximity of labeled molecules. This technique is useful for studying interactions of molecules and PROTEIN FOLDING.Protein Folding: Processes involved in the formation of TERTIARY PROTEIN STRUCTURE.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.Phosphorylation: The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.Sequence Deletion: Deletion of sequences of nucleic acids from the genetic material of an individual.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.Escherichia coli: A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.Circular Dichroism: A change from planar to elliptic polarization when an initially plane-polarized light wave traverses an optically active medium. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Mutagenesis: Process of generating a genetic MUTATION. It may occur spontaneously or be induced by MUTAGENS.Mutant Proteins: Proteins produced from GENES that have acquired MUTATIONS.Bacterial Proteins: Proteins found in any species of bacterium.Chromatography, Gel: Chromatography on non-ionic gels without regard to the mechanism of solute discrimination.Helix-Loop-Helix Motifs: Recurring supersecondary structures characterized by 20 amino acids folding into two alpha helices connected by a non-helical "loop" segment. They are found in many sequence-specific DNA-BINDING PROTEINS and in CALCIUM-BINDING PROTEINS.Nucleic Acid Conformation: The spatial arrangement of the atoms of a nucleic acid or polynucleotide that results in its characteristic 3-dimensional shape.Point Mutation: A mutation caused by the substitution of one nucleotide for another. This results in the DNA molecule having a change in a single base pair.RNA, Viral: Ribonucleic acid that makes up the genetic material of viruses.Glycophorin: The major sialoglycoprotein of the human erythrocyte membrane. It consists of at least two sialoglycopeptides and is composed of 60% carbohydrate including sialic acid and 40% protein. It is involved in a number of different biological activities including the binding of MN blood groups, influenza viruses, kidney bean phytohemagglutinin, and wheat germ agglutinin.Two-Hybrid System Techniques: Screening techniques first developed in yeast to identify genes encoding interacting proteins. Variations are used to evaluate interplay between proteins and other molecules. Two-hybrid techniques refer to analysis for protein-protein interactions, one-hybrid for DNA-protein interactions, three-hybrid interactions for RNA-protein interactions or ligand-based interactions. Reverse n-hybrid techniques refer to analysis for mutations or other small molecules that dissociate known interactions.Repressor Proteins: Proteins which maintain the transcriptional quiescence of specific GENES or OPERONS. Classical repressor proteins are DNA-binding proteins that are normally bound to the OPERATOR REGION of an operon, or the ENHANCER SEQUENCES of a gene until a signal occurs that causes their release.Conserved Sequence: A sequence of amino acids in a polypeptide or of nucleotides in DNA or RNA that is similar across multiple species. A known set of conserved sequences is represented by a CONSENSUS SEQUENCE. AMINO ACID MOTIFS are often composed of conserved sequences.Basic-Leucine Zipper Transcription Factors: A large superfamily of transcription factors that contain a region rich in BASIC AMINO ACID residues followed by a LEUCINE ZIPPER domain.Enzyme Activation: Conversion of an inactive form of an enzyme to one possessing metabolic activity. It includes 1, activation by ions (activators); 2, activation by cofactors (coenzymes); and 3, conversion of an enzyme precursor (proenzyme or zymogen) to an active enzyme.Electrophoresis, Polyacrylamide Gel: Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.HEK293 Cells: A cell line generated from human embryonic kidney cells that were transformed with human adenovirus type 5.Models, Biological: Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.Trans-Activators: Diffusible gene products that act on homologous or heterologous molecules of viral or cellular DNA to regulate the expression of proteins.Transcriptional Activation: Processes that stimulate the GENETIC TRANSCRIPTION of a gene or set of genes.Thermodynamics: A rigorously mathematical analysis of energy relationships (heat, work, temperature, and equilibrium). It describes systems whose states are determined by thermal parameters, such as temperature, in addition to mechanical and electromagnetic parameters. (From Hawley's Condensed Chemical Dictionary, 12th ed)HIV-1: The type species of LENTIVIRUS and the etiologic agent of AIDS. It is characterized by its cytopathic effect and affinity for the T4-lymphocyte.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.Cell Membrane: The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.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.Virus Assembly: The assembly of VIRAL STRUCTURAL PROTEINS and nucleic acid (VIRAL DNA or VIRAL RNA) to form a VIRUS PARTICLE.Peptide Fragments: Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.Catalytic Domain: The region of an enzyme that interacts with its substrate to cause the enzymatic reaction.DNA Primers: Short sequences (generally about 10 base pairs) of DNA that are complementary to sequences of messenger RNA and allow reverse transcriptases to start copying the adjacent sequences of mRNA. Primers are used extensively in genetic and molecular biology techniques.Catalysis: The facilitation of a chemical reaction by material (catalyst) that is not consumed by the reaction.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.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.CHO Cells: CELL LINE derived from the ovary of the Chinese hamster, Cricetulus griseus (CRICETULUS). The species is a favorite for cytogenetic studies because of its small chromosome number. The cell line has provided model systems for the study of genetic alterations in cultured mammalian cells.Zinc Fingers: Motifs in DNA- and RNA-binding proteins whose amino acids are folded into a single structural unit around a zinc atom. In the classic zinc finger, one zinc atom is bound to two cysteines and two histidines. In between the cysteines and histidines are 12 residues which form a DNA binding fingertip. By variations in the composition of the sequences in the fingertip and the number and spacing of tandem repeats of the motif, zinc fingers can form a large number of different sequence specific binding sites.Cricetinae: A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.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.Precipitin Tests: Serologic tests in which a positive reaction manifested by visible CHEMICAL PRECIPITATION occurs when a soluble ANTIGEN reacts with its precipitins, i.e., ANTIBODIES that can form a precipitate.Hydrophobic and Hydrophilic Interactions: The thermodynamic interaction between a substance and WATER.Nuclear Magnetic Resonance, Biomolecular: NMR spectroscopy on small- to medium-size biological macromolecules. This is often used for structural investigation of proteins and nucleic acids, and often involves more than one isotope.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.Hydrogen Bonding: A low-energy attractive force between hydrogen and another element. It plays a major role in determining the properties of water, proteins, and other compounds.gag Gene Products, Human Immunodeficiency Virus: Proteins encoded by the GAG GENE of the HUMAN IMMUNODEFICIENCY VIRUS.Magnetic Resonance Spectroscopy: Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).Glutaral: One of the protein CROSS-LINKING REAGENTS that is used as a disinfectant for sterilization of heat-sensitive equipment and as a laboratory reagent, especially as a fixative.Peptides: Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are linear polypeptides that are normally synthesized on RIBOSOMES.Protein Stability: The ability of a protein to retain its structural conformation or its activity when subjected to physical or chemical manipulations.Membrane Proteins: Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.Spectrometry, Fluorescence: Measurement of the intensity and quality of fluorescence.Escherichia coli Proteins: Proteins obtained from ESCHERICHIA COLI.Protein Transport: The process of moving proteins from one cellular compartment (including extracellular) to another by various sorting and transport mechanisms such as gated transport, protein translocation, and vesicular transport.Protein Subunits: Single chains of amino acids that are the units of multimeric PROTEINS. Multimeric proteins can be composed of identical or non-identical subunits. One or more monomeric subunits may compose a protomer which itself is a subunit structure of a larger assembly.Structural Homology, Protein: The degree of 3-dimensional shape similarity between proteins. It can be an indication of distant AMINO ACID SEQUENCE HOMOLOGY and used for rational DRUG DESIGN.Solutions: The homogeneous mixtures formed by the mixing of a solid, liquid, or gaseous substance (solute) with a liquid (the solvent), from which the dissolved substances can be recovered by physical processes. (From Grant & Hackh's Chemical Dictionary, 5th ed)Carrier Proteins: Transport proteins that carry specific substances in the blood or across cell membranes.RNA, Double-Stranded: RNA consisting of two strands as opposed to the more prevalent single-stranded RNA. Most of the double-stranded segments are formed from transcription of DNA by intramolecular base-pairing of inverted complementary sequences separated by a single-stranded loop. Some double-stranded segments of RNA are normal in all organisms.AraC Transcription Factor: A transcription factor found in BACTERIA that positively and negatively regulates the expression of proteins required for the uptake and catabolism of L-ARABINOSE.Saccharomyces cerevisiae: A species of the genus SACCHAROMYCES, family Saccharomycetaceae, order Saccharomycetales, known as "baker's" or "brewer's" yeast. The dried form is used as a dietary supplement.Receptor, Epidermal Growth Factor: A cell surface receptor involved in regulation of cell growth and differentiation. It is specific for EPIDERMAL GROWTH FACTOR and EGF-related peptides including TRANSFORMING GROWTH FACTOR ALPHA; AMPHIREGULIN; and HEPARIN-BINDING EGF-LIKE GROWTH FACTOR. The binding of ligand to the receptor causes activation of its intrinsic tyrosine kinase activity and rapid internalization of the receptor-ligand complex into the cell.Aryl Hydrocarbon Receptor Nuclear Translocator: Aryl hydrocarbon receptor nuclear translocator is a basic HELIX-LOOP-HELIX MOTIF containing protein that forms a complex with DIOXIN RECEPTOR. The complex binds xenobiotic regulatory elements and activates transcription of a variety of genes including UDP GLUCURONOSYLTRANSFERASE. AhR nuclear translocator is also a subunit of HYPOXIA-INDUCIBLE FACTOR 1.Genome, Viral: The complete genetic complement contained in a DNA or RNA molecule in a virus.Saccharomyces cerevisiae Proteins: Proteins obtained from the species SACCHAROMYCES CEREVISIAE. The function of specific proteins from this organism are the subject of intense scientific interest and have been used to derive basic understanding of the functioning similar proteins in higher eukaryotes.Protein Processing, Post-Translational: Any of various enzymatically catalyzed post-translational modifications of PEPTIDES or PROTEINS in the cell of origin. These modifications include carboxylation; HYDROXYLATION; ACETYLATION; PHOSPHORYLATION; METHYLATION; GLYCOSYLATION; ubiquitination; oxidation; proteolysis; and crosslinking and result in changes in molecular weight and electrophoretic motility.DNA Mutational Analysis: Biochemical identification of mutational changes in a nucleotide sequence.Scattering, Radiation: The diversion of RADIATION (thermal, electromagnetic, or nuclear) from its original path as a result of interactions or collisions with atoms, molecules, or larger particles in the atmosphere or other media. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Tacrolimus Binding Proteins: A family of immunophilin proteins that bind to the immunosuppressive drugs TACROLIMUS (also known as FK506) and SIROLIMUS. EC 5.2.1.-Transcription Factor 7-Like 1 Protein: A transcription factor that takes part in WNT signaling pathway where it may play a role in the differentiation of KERATINOCYTES. The transcriptional activity of this protein is regulated via its interaction with BETA CATENIN.Cricetulus: A genus of the family Muridae consisting of eleven species. C. migratorius, the grey or Armenian hamster, and C. griseus, the Chinese hamster, are the two species used in biomedical research.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.Cyclic GMP-Dependent Protein Kinase Type I: A cyclic GMP-dependent protein kinase subtype that is expressed in SMOOTH MUSCLE tissues and plays a role in regulation of smooth muscle contraction. Two isoforms, PKGIalpha and PKGIbeta, of the type I protein kinase exist due to alternative splicing of its mRNA.Protein Isoforms: Different forms of a protein that may be produced from different GENES, or from the same gene by ALTERNATIVE SPLICING.Molecular Weight: The sum of the weight of all the atoms in a molecule.Cytoplasm: The part of a cell that contains the CYTOSOL and small structures excluding the CELL NUCLEUS; MITOCHONDRIA; and large VACUOLES. (Glick, Glossary of Biochemistry and Molecular Biology, 1990)Molecular Conformation: The characteristic three-dimensional shape of a molecule.G-Box Binding Factors: A family of transcription factors found primarily in PLANTS that bind to the G-box DNA sequence CACGTG or to a consensus sequence CANNTG.Oligodeoxyribonucleotides: A group of deoxyribonucleotides (up to 12) in which the phosphate residues of each deoxyribonucleotide act as bridges in forming diester linkages between the deoxyribose moieties.HSP90 Heat-Shock Proteins: A class of MOLECULAR CHAPERONES whose members act in the mechanism of SIGNAL TRANSDUCTION by STEROID RECEPTORS.Viral Proteins: Proteins found in any species of virus.Crystallization: The formation of crystalline substances from solutions or melts. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Models, Chemical: Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.Immunoprecipitation: The aggregation of soluble ANTIGENS with ANTIBODIES, alone or with antibody binding factors such as ANTI-ANTIBODIES or STAPHYLOCOCCAL PROTEIN A, into complexes large enough to fall out of solution.Temperature: The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.Static Electricity: The accumulation of an electric charge on a objectMutation, Missense: A mutation in which a codon is mutated to one directing the incorporation of a different amino acid. This substitution may result in an inactive or unstable product. (From A Dictionary of Genetics, King & Stansfield, 5th ed)Rous sarcoma virus: A species of replication-competent oncogene-containing virus in the genus ALPHARETROVIRUS. It is the original source of the src oncogene (V-SRC GENES) and causes sarcoma in chickens.Receptor Protein-Tyrosine Kinases: A class of cellular receptors that have an intrinsic PROTEIN-TYROSINE KINASE activity.DNA, Complementary: Single-stranded complementary DNA synthesized from an RNA template by the action of RNA-dependent DNA polymerase. cDNA (i.e., complementary DNA, not circular DNA, not C-DNA) is used in a variety of molecular cloning experiments as well as serving as a specific hybridization probe.Molecular Structure: The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.Spodoptera: A genus of owlet moths of the family Noctuidae. These insects are used in molecular biology studies during all stages of their life cycle.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.5' Untranslated Regions: The sequence at the 5' end of the messenger RNA that does not code for product. This sequence contains the ribosome binding site and other transcription and translation regulating sequences.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.Blotting, Western: Identification of proteins or peptides that have been electrophoretically separated by blot transferring from the electrophoresis gel to strips of nitrocellulose paper, followed by labeling with antibody probes.Substrate Specificity: A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.Basic Helix-Loop-Helix Leucine Zipper Transcription Factors: A family of transcription factors that contain regions rich in basic residues, LEUCINE ZIPPER domains, and HELIX-LOOP-HELIX MOTIFS.Adenosine Triphosphatases: A group of enzymes which catalyze the hydrolysis of ATP. The hydrolysis reaction is usually coupled with another function such as transporting Ca(2+) across a membrane. These enzymes may be dependent on Ca(2+), Mg(2+), anions, H+, or DNA.Fluorescence: The property of emitting radiation while being irradiated. The radiation emitted is usually of longer wavelength than that incident or absorbed, e.g., a substance can be irradiated with invisible radiation and emit visible light. X-ray fluorescence is used in diagnosis.Allosteric Regulation: The modification of the reactivity of ENZYMES by the binding of effectors to sites (ALLOSTERIC SITES) on the enzymes other than the substrate BINDING SITES.Tyrosine: A non-essential amino acid. In animals it is synthesized from PHENYLALANINE. It is also the precursor of EPINEPHRINE; THYROID HORMONES; and melanin.Glutathione Transferase: A transferase that catalyzes the addition of aliphatic, aromatic, or heterocyclic FREE RADICALS as well as EPOXIDES and arene oxides to GLUTATHIONE. Addition takes place at the SULFUR. It also catalyzes the reduction of polyol nitrate by glutathione to polyol and nitrite.Drosophila Proteins: Proteins that originate from insect species belonging to the genus DROSOPHILA. The proteins from the most intensely studied species of Drosophila, DROSOPHILA MELANOGASTER, are the subject of much interest in the area of MORPHOGENESIS and development.Receptors, Somatotropin: Cell surface proteins that bind GROWTH HORMONE with high affinity and trigger intracellular changes influencing the behavior of cells. Activation of growth hormone receptors regulates amino acid transport through cell membranes, RNA translation to protein, DNA transcription, and protein and amino acid catabolism in many cell types. Many of these effects are mediated indirectly through stimulation of the release of somatomedins.Aminocoumarins: COUMARINS with an amino group, exemplified by NOVOBIOCIN.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.Molecular Chaperones: A family of cellular proteins that mediate the correct assembly or disassembly of polypeptides and their associated ligands. Although they take part in the assembly process, molecular chaperones are not components of the final structures.14-3-3 Proteins: A large family of signal-transducing adaptor proteins present in wide variety of eukaryotes. They are PHOSPHOSERINE and PHOSPHOTHREONINE binding proteins involved in important cellular processes including SIGNAL TRANSDUCTION; CELL CYCLE control; APOPTOSIS; and cellular stress responses. 14-3-3 proteins function by interacting with other signal-transducing proteins and effecting changes in their enzymatic activity and subcellular localization. The name 14-3-3 derives from numerical designations used in the original fractionation patterns of the proteins.Glycosylation: The chemical or biochemical addition of carbohydrate or glycosyl groups to other chemicals, especially peptides or proteins. Glycosyl transferases are used in this biochemical reaction.HIV Protease: Enzyme of the human immunodeficiency virus that is required for post-translational cleavage of gag and gag-pol precursor polyproteins into functional products needed for viral assembly. HIV protease is an aspartic protease encoded by the amino terminus of the pol gene.Adaptor Proteins, Signal Transducing: A broad category of carrier proteins that play a role in SIGNAL TRANSDUCTION. They generally contain several modular domains, each of which having its own binding activity, and act by forming complexes with other intracellular-signaling molecules. Signal-transducing adaptor proteins lack enzyme activity, however their activity can be modulated by other signal-transducing enzymesCell Nucleus: Within a eukaryotic cell, a membrane-limited body which contains chromosomes and one or more nucleoli (CELL NUCLEOLUS). The nuclear membrane consists of a double unit-type membrane which is perforated by a number of pores; the outermost membrane is continuous with the ENDOPLASMIC RETICULUM. A cell may contain more than one nucleus. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)Green Fluorescent Proteins: Protein analogs and derivatives of the Aequorea victoria green fluorescent protein that emit light (FLUORESCENCE) when excited with ULTRAVIOLET RAYS. They are used in REPORTER GENES in doing GENETIC TECHNIQUES. Numerous mutants have been made to emit other colors or be sensitive to pH.Receptor Aggregation: Chemically stimulated aggregation of cell surface receptors, which potentiates the action of the effector cell.Surface Plasmon Resonance: A biosensing technique in which biomolecules capable of binding to specific analytes or ligands are first immobilized on one side of a metallic film. Light is then focused on the opposite side of the film to excite the surface plasmons, that is, the oscillations of free electrons propagating along the film's surface. The refractive index of light reflecting off this surface is measured. When the immobilized biomolecules are bound by their ligands, an alteration in surface plasmons on the opposite side of the film is created which is directly proportional to the change in bound, or adsorbed, mass. Binding is measured by changes in the refractive index. The technique is used to study biomolecular interactions, such as antigen-antibody binding.Luminescent Proteins: Proteins which are involved in the phenomenon of light emission in living systems. Included are the "enzymatic" and "non-enzymatic" types of system with or without the presence of oxygen or co-factors.Nucleocapsid: A protein-nucleic acid complex which forms part or all of a virion. It consists of a CAPSID plus enclosed nucleic acid. Depending on the virus, the nucleocapsid may correspond to a naked core or be surrounded by a membranous envelope.Bioluminescence Resonance Energy Transfer Techniques: Techniques for determining the proximity of molecules based on ENERGY TRANSFER between bioluminescent chromophores and acceptor fluorophores that have overlapping emission and absorption spectra.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.Microscopy, Fluorescence: Microscopy of specimens stained with fluorescent dye (usually fluorescein isothiocyanate) or of naturally fluorescent materials, which emit light when exposed to ultraviolet or blue light. Immunofluorescence microscopy utilizes antibodies that are labeled with fluorescent dye.Hydrolysis: The process of cleaving a chemical compound by the addition of a molecule of water.Fungal Proteins: Proteins found in any species of fungus.Multiprotein Complexes: Macromolecular complexes formed from the association of defined protein subunits.Protein Denaturation: Disruption of the non-covalent bonds and/or disulfide bonds responsible for maintaining the three-dimensional shape and activity of the native protein.Receptor, erbB-3: A cell surface protein-tyrosine kinase receptor that is specific for NEUREGULINS. It has extensive homology to and can heterodimerize with the EGF RECEPTOR and the ERBB-2 RECEPTOR. Overexpression of the erbB-3 receptor is associated with TUMORIGENESIS.

Transcriptional repression by the Drosophila giant protein: cis element positioning provides an alternative means of interpreting an effector gradient. (1/13650)

Early developmental patterning of the Drosophila embryo is driven by the activities of a diverse set of maternally and zygotically derived transcription factors, including repressors encoded by gap genes such as Kruppel, knirps, giant and the mesoderm-specific snail. The mechanism of repression by gap transcription factors is not well understood at a molecular level. Initial characterization of these transcription factors suggests that they act as short-range repressors, interfering with the activity of enhancer or promoter elements 50 to 100 bp away. To better understand the molecular mechanism of short-range repression, we have investigated the properties of the Giant gap protein. We tested the ability of endogenous Giant to repress when bound close to the transcriptional initiation site and found that Giant effectively represses a heterologous promoter when binding sites are located at -55 bp with respect to the start of transcription. Consistent with its role as a short-range repressor, as the binding sites are moved to more distal locations, repression is diminished. Rather than exhibiting a sharp 'step-function' drop-off in activity, however, repression is progressively restricted to areas of highest Giant concentration. Less than a two-fold difference in Giant protein concentration is sufficient to determine a change in transcriptional status of a target gene. This effect demonstrates that Giant protein gradients can be differentially interpreted by target promoters, depending on the exact location of the Giant binding sites within the gene. Thus, in addition to binding site affinity and number, cis element positioning within a promoter can affect the response of a gene to a repressor gradient. We also demonstrate that a chimeric Gal4-Giant protein lacking the basic/zipper domain can specifically repress reporter genes, suggesting that the Giant effector domain is an autonomous repression domain.  (+info)

Four dimers of lambda repressor bound to two suitably spaced pairs of lambda operators form octamers and DNA loops over large distances. (2/13650)

Transcription factors that are bound specifically to DNA often interact with each other over thousands of base pairs [1] [2]. Large DNA loops resulting from such interactions have been observed in Escherichia coli with the transcription factors deoR [3] and NtrC [4], but such interactions are not, as yet, well understood. We propose that unique protein complexes, that are not present in solution, may form specifically on DNA. Their uniqueness would make it possible for them to interact tightly and specifically with each other. We used the repressor and operators of coliphage lambda to construct a model system in which to test our proposition. lambda repressor is a dimer at physiological concentrations, but forms tetramers and octamers at a hundredfold higher concentration. We predict that two lambda repressor dimers form a tetramer in vitro when bound to two lambda operators spaced 24 bp apart and that two such tetramers interact to form an octamer. We examined, in vitro, relaxed circular plasmid DNA in which such operator pairs were separated by 2,850 bp and 2,470 bp. Of these molecules, 29% formed loops as seen by electron microscopy (EM). The loop increased the tightness of binding of lambda repressor to lambda operator. Consequently, repression of the lambda PR promoter in vivo was increased fourfold by the presence of a second pair of lambda operators, separated by a distance of 3,600 bp.  (+info)

ETO-2, a new member of the ETO-family of nuclear proteins. (3/13650)

The t(8;21) is associated with 12-15% of acute myelogenous leukemias of the M2 subtype. The translocation results in the fusion of two genes, AML1 (CBFA2) on chromosome 21 and ETO (MTG8) on chromosome 8. AML1 encodes a DNA binding factor; the ETO protein product is less well characterized, but is thought to be a transcription factor. Here we describe the isolation and characterization of ETO-2, a murine cDNA that encodes a new member of the ETO family of proteins. ETO-2 is 75% identical to murine ETO and shares very high sequence identities over four regions of the protein with ETO (domain I-III and zinc-finger). Northern analysis identifies ETO-2 transcripts in many of the murine tissues analysed and in the developing mouse embryo. ETO-2 is also expressed in myeloid and erythroid cell lines. We confirmed the nuclear localization of ETO-2 and demonstrated that domain III and the zinc-finger region are not required for nuclear localization. We further showed that a region within ETO, containing domain II, mediates dimerization among family members. This region is conserved in the oncoprotein AML-1/ETO. The recent identification of another ETO-like protein, myeloid translocation gene-related protein 1, together with the data presented here, demonstrates that at least three ETO proteins exist with the potential to form dimers in the cell nucleus.  (+info)

Coupling of the cell cycle and myogenesis through the cyclin D1-dependent interaction of MyoD with cdk4. (4/13650)

Proliferating myoblasts express the muscle determination factor, MyoD, throughout the cell cycle in the absence of differentiation. Here we show that a mitogen-sensitive mechanism, involving the direct interaction between MyoD and cdk4, restricts myoblast differentiation to cells that have entered into the G0 phase of the cell cycle under mitogen withdrawal. Interaction between MyoD and cdk4 disrupts MyoD DNA-binding, muscle-specific gene activation and myogenic conversion of 10T1/2 cells independently of cyclin D1 and the CAK activation of cdk4. Forced induction of cyclin D1 in myotubes results in the cytoplasmic to nuclear translocation of cdk4. The specific MyoD-cdk4 interaction in dividing myoblasts, coupled with the cyclin D1-dependent nuclear targeting of cdk4, suggests a mitogen-sensitive mechanism whereby cyclin D1 can regulate MyoD function and the onset of myogenesis by controlling the cellular location of cdk4 rather than the phosphorylation status of MyoD.  (+info)

Assembly requirements of PU.1-Pip (IRF-4) activator complexes: inhibiting function in vivo using fused dimers. (5/13650)

Gene expression in higher eukaryotes appears to be regulated by specific combinations of transcription factors binding to regulatory sequences. The Ets factor PU.1 and the IRF protein Pip (IRF-4) represent a pair of interacting transcription factors implicated in regulating B cell-specific gene expression. Pip is recruited to its binding site on DNA by phosphorylated PU.1. PU.1-Pip interaction is shown to be template directed and involves two distinct protein-protein interaction surfaces: (i) the ets and IRF DNA-binding domains; and (ii) the phosphorylated PEST region of PU.1 and a lysine-requiring putative alpha-helix in Pip. Thus, a coordinated set of protein-protein and protein-DNA contacts are essential for PU.1-Pip ternary complex assembly. To analyze the function of these factors in vivo, we engineered chimeric repressors containing the ets and IRF DNA-binding domains connected by a flexible POU domain linker. When stably expressed, the wild-type fused dimer strongly repressed the expression of a rearranged immunoglobulin lambda gene, thereby establishing the functional importance of PU.1-Pip complexes in B cell gene expression. Comparative analysis of the wild-type dimer with a series of mutant dimers distinguished a gene regulated by PU.1 and Pip from one regulated by PU.1 alone. This strategy should prove generally useful in analyzing the function of interacting transcription factors in vivo, and for identifying novel genes regulated by such complexes.  (+info)

p50(cdc37) acting in concert with Hsp90 is required for Raf-1 function. (6/13650)

Genetic screens in Drosophila have identified p50(cdc37) to be an essential component of the sevenless receptor/mitogen-activated kinase protein (MAPK) signaling pathway, but neither the function nor the target of p50(cdc37) in this pathway has been defined. In this study, we examined the role of p50(cdc37) and its Hsp90 chaperone partner in Raf/Mek/MAPK signaling biochemically. We found that coexpression of wild-type p50(cdc37) with Raf-1 resulted in robust and dose-dependent activation of Raf-1 in Sf9 cells. In addition, p50(cdc37) greatly potentiated v-Src-mediated Raf-1 activation. Moreover, we found that p50(cdc37) is the primary determinant of Hsp90 recruitment to Raf-1. Overexpression of a p50(cdc37) mutant which is unable to recruit Hsp90 into the Raf-1 complex inhibited Raf-1 and MAPK activation by growth factors. Similarly, pretreatment with geldanamycin (GA), an Hsp90-specific inhibitor, prevented both the association of Raf-1 with the p50(cdc37)-Hsp90 heterodimer and Raf-1 kinase activation by serum. Activation of Raf-1 via baculovirus coexpression with oncogenic Src or Ras in Sf9 cells was also strongly inhibited by dominant negative p50(cdc37) or by GA. Thus, formation of a ternary Raf-1-p50(cdc37)-Hsp90 complex is crucial for Raf-1 activity and MAPK pathway signaling. These results provide the first biochemical evidence for the requirement of the p50(cdc37)-Hsp90 complex in protein kinase regulation and for Raf-1 function in particular.  (+info)

C/EBPalpha regulates generation of C/EBPbeta isoforms through activation of specific proteolytic cleavage. (7/13650)

C/EBPalpha and C/EBPbeta are intronless genes that can produce several N-terminally truncated isoforms through the process of alternative translation initiation at downstream AUG codons. C/EBPbeta has been reported to produce four isoforms: full-length 38-kDa C/EBPbeta, 35-kDa LAP (liver-enriched transcriptional activator protein), 21-kDa LIP (liver-enriched transcriptional inhibitory protein), and a 14-kDa isoform. In this report, we investigated the mechanisms by which C/EBPbeta isoforms are generated in the liver and in cultured cells. Using an in vitro translation system, we found that LIP can be generated by two mechanisms: alternative translation and a novel mechanism-specific proteolytic cleavage of full-length C/EBPbeta. Studies of mice in which the C/EBPalpha gene had been deleted (C/EBPalpha-/-) showed that the regulation of C/EBPbeta proteolysis is dependent on C/EBPalpha. The induction of C/EBPalpha in cultured cells leads to induced cleavage of C/EBPbeta to generate the LIP isoform. We characterized the cleavage activity in mouse liver extracts and found that the proteolytic cleavage activity is specific to prenatal and newborn livers, is sensitive to chymostatin, and is completely abolished in C/EBPalpha-/- animals. The lack of cleavage activity in the livers of C/EBPalpha-/- mice correlates with the decreased levels of LIP in the livers of these animals. Analysis of LIP production during liver regeneration showed that, in this system, the transient induction of LIP is dependent on the third AUG codon and most likely involves translational control. We propose that there are two mechanisms by which C/EBPbeta isoforms might be generated in the liver and in cultured cells: one that is determined by translation and a second that involves C/EBPalpha-dependent, specific proteolytic cleavage of full-length C/EBPbeta. The latter mechanism implicates C/EBPalpha in the regulation of posttranslational generation of the dominant negative C/EBPbeta isoform, LIP.  (+info)

The significance of tetramerization in promoter recruitment by Stat5. (8/13650)

Stat5a and Stat5b are rapidly activated by a wide range of cytokines and growth factors, including interleukin-2 (IL-2). We have previously shown that these signal transducers and activators of transcription (STAT proteins) are key regulatory proteins that bind to two tandem gamma interferon-activated site (GAS) motifs within an IL-2 response element (positive regulatory region III [PRRIII]) in the human IL-2Ralpha promoter. In this study, we demonstrate cooperative binding of Stat5 to PRRIII and explore the molecular basis underlying this cooperativity. We demonstrate that formation of a tetrameric Stat5 complex is essential for the IL-2-inducible activation of PRRIII. Stable tetramer formation of Stat5 is mediated through protein-protein interactions involving a tryptophan residue conserved in all STATs and a lysine residue in the Stat5 N-terminal domain (N domain). The functional importance of tetramer formation is shown by the decreased levels of transcriptional activation associated with mutations in these residues. Moreover, the requirement for STAT protein-protein interactions for gene activation from a promoter with tandemly linked GAS motifs can be relieved by strengthening the avidity of protein-DNA interactions for the individual binding sites. Taken together, these studies demonstrate that a dimeric but tetramerization-deficient Stat5 protein can activate only a subset of target sites. For functional activity on a wider range of potential recognition sites, N-domain-mediated oligomerization is essential.  (+info)

  • In addition, by analyzing a construct, encoding only the carboxy-terminal 151 amino acids of vWF, we find that the formation of dimers is an event independent of other domains present on pro-vWF, such as the domains C1 and C2 previously suggested to be involved in dimerization. (rupress.org)
  • We show that dimerization is crucial for IRAK4 autophosphorylation invitro and ligand-dependent signaling in cells. (mendeley.com)
  • Quantitative investigations through molecular diffusion and adsorption kinetics show that Btk undergoes dimerization-mediated activation in a PIP 3 density-dependent manner, providing a ligand-counting mechanism with a sharp sensitivity to signal strength. (pnas.org)
  • While stable in CH 2 Cl 2 , hexane or THF, in the presence of MeOH, self-promoted dimerization of the triarylphosphine-alkene 1 , a ligand for Pd-catalyzed reactions, produced an unusual racemic bis(phosphine) 2 in high yield. (springer.com)
  • 3 different RGD-containing ligands (including Integrilin) are used to form receptor-ligand complexes, and measured dimerization of ligand-bound receptors as a fuction of temperature in the range 20-40C using a variety of methods. (physicsforums.com)
  • 40 1.79*10^6 3.47*10^6 4.00*10^5 a) which ligand leads to the greates degree of dimerization of the integrin-ligand complex at 20C? (physicsforums.com)
  • The D/D Solubilizer is a synthetic, cell-permeable ligand that can be used to disrupt dimerization of fusion proteins containing the DmrD domain. (clontech.com)
  • The results suggest that those metalloporphyrins which caused dimerization were able to acquire a thiolate ligand from the protein, and we propose that this ligation is the trigger for dimerization. (biochemj.org)
  • Pertuzumab (rhuMAb 2C4), a humanized HER2 antibody, represents a new class of targeted therapeutics that inhibit dimerization of HER2 with ligand-activated EGFR (HER1), HER3, and HER-4. (aacrjournals.org)
  • Functional characterization included the determination of total expression, cell surface expression and dimerisation studies by a sandwich-ELISA approach as well as ligand binding and signal transduction properties. (endocrine-abstracts.org)
  • We present the first report of a peptidomimetic approach to design of small-molecule inhibitors of Stat3 that are also among the first examples of disruptors of transcription factor dimerization with the potential for novel cancer therapy. (aacrjournals.org)
  • Our findings also provide proof-of-principle that small-molecule inhibitors of Stat3 represent potential novel cancer therapeutic agents, and together with an earlier report of a peptidomimetic inhibitor of Myc/Max ( 22 ) are among the first examples of small-molecule inhibitors of transcription factor dimerization ( 1 ). (aacrjournals.org)
  • This approach is questionable, however, due to virus mutations and the high toxicity of the drugs, An alternative method to inhibit the dimeric HIV protease is the targeting of the interface region of the protease subunits in order to prevent subunit dimerization and enzyme activity, This approach should be less prone to inactivation by mutation, A list of improved 'dimerization inhibitors' of HIV-1 protease is presented. (uni-muenchen.de)
  • The BglG phosphorylation site, His 208 , resides at the junction of the two putative dimerization domains. (asm.org)
  • Possible mechanisms by which the phosphorylation of BglG controls its dimerization and thus its activity are discussed. (asm.org)
  • As part of the global effort to elucidate the mechanism by which reversible phosphorylation of BglG, in response to an environmental stimulus, controls its dimeric state, we attempted to map its dimerization site relative to the phosphorylation site and characterize it. (asm.org)
  • It is especially demanding for members of the OmpR/PhoB subfamily, the largest RR subfamily, which share a conserved dimerization interface for phosphorylation-mediated transcription regulation. (pubmedcentralcanada.ca)
  • The Absolute Configuration of Rhizopodin and Its Inhibition of Actin Polymerization by Dimerization. (docme.ru)
  • Angewandte Chemie DOI: 10.1002/anie.200802915 Protein-Inhibitor Complexes The Absolute Configuration of Rhizopodin and Its Inhibition of Actin Polymerization by Dimerization** Gregor Hagelueken, Simone C. Albrecht, Heinrich Steinmetz, Rolf Jansen, Dirk W. Heinz, Markus Kalesse, and Wolf-Dieter Schubert* In 1993 the novel polyketide rhizopodin (Figure 1) was isolated from the myxobacterium Myxococcus stipitatus. (docme.ru)
  • Here, we report an inhibitor of NADH-dependent dimerization of the C-terminal binding protein (CtBP) transcriptional repressor, identified by screening genetically encoded cyclic peptide libraries of up to 64 million members. (soton.ac.uk)
  • The most potent inhibitor from our screen (cyclo-SGWTVVRMY) is demonstrated to disrupt CtBP dimerization in vitro and in cells. (soton.ac.uk)
  • Dimerization is driven by interactions that are specific, dominated by the helix-helix interface, and involve no potentially ionizable groups. (nih.gov)
  • The iDimerize Reverse Dimerization System brings the disruption of protein complexes under real-time, small molecule control. (clontech.com)
  • Bacteria downregulate their ribosomal activity through dimerization of 70S ribosomes, yielding inactive 100S complexes. (rug.nl)
  • Together, this data suggest a novel model whereby Bet uses two possibly complementary mechanisms to counteract A3G: (1) Bet prevents encapsidation of A3G by blocking A3G dimerization, and (2) sequesters A3G in immobile complexes, impairing its ability to interact with nascent virions. (epfl.ch)
  • ATP-induced domain dimerization and DNA binding for SMC and Rad50 complexes. (nih.gov)
  • This inter-complex dimerization may be favored between complexes bound near each other on DNA. (nih.gov)
  • Carbene dimerization is a type of organic reaction in which two carbene or carbenoid precursors react in a formal dimerization to an alkene. (wikipedia.org)
  • Disclosed herein are processes for tandem alkene dehydrogenation/alkene dimerization using an iridium pincer complex catalyst on a support comprising magnesium. (patents.com)
  • The iDimerize Reverse Dimerization System is a "reverse dimerization" system-aggregation is the resting state, and the D/D Solubilizer breaks up protein-protein interactions. (clontech.com)
  • On the basis of the known importance of pTyr-SH2 interactions for STAT dimerization ( 11 , 19 , 20 ), we previously identified a dimerization-disrupting phosphopeptide sequence that is derived from the SH2 domain-binding region of Stat3, PY*LKTK (where Y* represents phosphotyrosine) and its tripeptide derivatives PY*L and AY*L, as inhibitors of Stat3 activation and biological function ( 21 ). (aacrjournals.org)
  • Moreover, the K88E mutant had even stronger dimerization ability, primarily due to interactions involving the C-terminal region. (asm.org)
  • To determine the possible impact of dimerization on redox-activation, AtGCL mutants were generated in which salt bridges or hydrophobic interactions at the dimer interface were interrupted. (portlandpress.com)
  • Sevoflurane increased dimer-dependent self-quenching and both decreased oligomer-dependent spectral shifting, suggesting that inhaled anesthetics promoted HSA dimerization. (hindawi.com)
  • Remarkably, K-Ras4B-GTP, but not GDP-bound, is able to form stable homodimers with different dimer interfaces, suggesting that the nucleotide-dependent dimerization with various dimer interfaces can resolve nanoclustering and cluster reorganization accomplishment with Raf's activation. (nih.gov)
  • Dimerization changed the chemical regioselectivity, substrate-binding affinity, and enzymatic activity of UGT1A1 and UGT1A9 in glucuronidation of quercetin. (sigmaaldrich.com)
  • Substrate and tetrahydrobiopterin binding sites only emerged with the metalloporphyrins that caused dimerization. (biochemj.org)
  • The telomerization is the linear dimerization of 1,3-dienes with simultaneous addition of a nucleophile in a catalytic reaction. (wikipedia.org)
  • The self heating process of Tetrafluoroethylene caused by an exothermic dimerization reaction was studied. (comsol.com)
  • EL222 was found to also exhibit photoinduced dimerization even in the absence of target DNA, although the yield of the reaction was low (∼0.08 compared with that of the EL-LOV domain). (rsc.org)
  • But recent studies of analogous receptors in bacteria indicate that dimerization may be only a prerequisite for signaling. (nih.gov)
  • Chen J, Nagle AM, Wang YF, Boone DN , Lee AV. Controlled dimerization of insulin-like grown factor-1 and insulin receptors reveal shared and distinct activities of holo and hybrid receptors. (pitt.edu)
  • In particular, we are interested in determining where PG1 dimerization is most favorable. (mdpi.com)
  • In Escherichia coli, dimerization is mediated by the hibernation promotion factor (HPF) and ribosome modulation factor. (rug.nl)
  • A direct metal carbene dimerization has been used in the synthesis of novel Polyalkynylethenes March, Jerry (1985), Advanced Organic Chemistry: Reactions, Mechanisms, and Structure (3rd ed. (wikipedia.org)
  • Structure-based mutagenesis reveals that TRAF6 dimerization is crucial for polyubiquitin synthesis and autoubiquitination. (nih.gov)
  • In spite of the dimerization defect, the genomic RNA from Myr1E particles serves efficiently as a template for reverse transcription as measured by an endogenous reverse transcriptase assay. (asm.org)
  • We report here a pattern of 7 amino acids (LIxxGVxxGVxxT) which when introduced into several hydrophobic transmembrane alpha-helices promotes their specific dimerization. (nih.gov)
  • This assembly relies on processing in the endoplasmic reticulum (ER) and involves multiple steps, including early association with the ER-resident chaperones calnexin/calreticulin and subsequent dimerization facilitated by lipase maturation factor 1 (LMF1) ( 19 - 23 ). (diabetesjournals.org)
  • It is concluded that the activation of PKG-1 α via H 2 O 2 -induced protein dimerization and subsequent opening of BK Ca channels serves as a novel mechanism of flow-induced H 2 O 2 -mediated relaxations in HCA. (ahajournals.org)
  • Here, we define the domains of vWF involved in dimerization, using deletion mutants of full-length vWF cDNA transiently expressed in monkey kidney COS-1 cells. (rupress.org)
  • 1997, 2163-2164 doi:10.1039/A706459D Maleates from diazoacetates and dilactones from head-to-head dimerisation of alkenyl diazoacetates using Grubbs' 2nd-generation ruthenium carbene catalyst David M. Hodgson and Deepshikha Angrish Chem. (wikipedia.org)
Structural basis for protein-protein interactions in the 14-3-3 protein family | PNAS
Structural basis for protein-protein interactions in the 14-3-3 protein family | PNAS (pnas.org)
Caspase - Wikipedia
Caspase - Wikipedia (en.wikipedia.org)
Nanosensing protein allostery using a bivalent mouse double minute two (MDM2) assay | PNAS
Nanosensing protein allostery using a bivalent mouse double minute two (MDM2) assay | PNAS (pnas.org)
Discuss briefly the difference between an orbit (as | bartleby
Discuss briefly the difference between an orbit (as | bartleby (bartleby.com)
Plus it
Plus it (jneurosci.org)
Asymmetric receptor contact is required for tyrosine autophosphorylation of fibroblast growth factor receptor in living cells |...
Asymmetric receptor contact is required for tyrosine autophosphorylation of fibroblast growth factor receptor in living cells |... (pnas.org)
Structural basis for inhibition of TLR2 by staphylococcal superantigen-like protein 3 (SSL3) | PNAS
Structural basis for inhibition of TLR2 by staphylococcal superantigen-like protein 3 (SSL3) | PNAS (pnas.org)
Three-dimensional aromaticity in an antiaromatic cyclophane | Nature Communications
Three-dimensional aromaticity in an antiaromatic cyclophane | Nature Communications (nature.com)
Structural basis for dimerization of the Dictyostelium gelation factor (ABP120) rod | Nature Structural & Molecular Biology
Structural basis for dimerization of the Dictyostelium gelation factor (ABP120) rod | Nature Structural & Molecular Biology (nature.com)
The impact of water on the ambivalent behavior and paradoxical phenomenon of the amyloid-β fibril protein : Biomolecular...
The impact of water on the ambivalent behavior and paradoxical phenomenon of the amyloid-β fibril protein : Biomolecular... (degruyter.com)
Frontiers | Three Rice NAC Transcription Factors Heteromerize and Are Associated with Seed Size | Plant Science
Frontiers | Three Rice NAC Transcription Factors Heteromerize and Are Associated with Seed Size | Plant Science (frontiersin.org)
Zeitschrift für Naturforschung A
Zeitschrift für Naturforschung A (degruyter.com)
Gal80 Dimerization and the Yeast GAL Gene Switch | Genetics
Gal80 Dimerization and the Yeast GAL Gene Switch | Genetics (genetics.org)
Gal80 Dimerization and the Yeast GAL Gene Switch | Genetics
Gal80 Dimerization and the Yeast GAL Gene Switch | Genetics (genetics.org)
Mutational Hypersensitivity of a Gene Regulatory Protein: Saccharomyces cerevisiae Gal80p | Genetics
Mutational Hypersensitivity of a Gene Regulatory Protein: Saccharomyces cerevisiae Gal80p | Genetics (genetics.org)
Contribution of Invariant Residues to the Function of Rgg Family Transcription Regulators | Journal of Bacteriology
Contribution of Invariant Residues to the Function of Rgg Family Transcription Regulators | Journal of Bacteriology (jb.asm.org)
Table of Contents - August 21, 2018, 11 (544) | Science Signaling
Table of Contents - August 21, 2018, 11 (544) | Science Signaling (stke.sciencemag.org)
MXI1 Gene - GeneCards | MXI1 Protein | MXI1 Antibody
MXI1 Gene - GeneCards | MXI1 Protein | MXI1 Antibody (genecards.org)
RCSB PDB - 6WZO: Structure of SARS-CoV-2 Nucleocapsid dimerization domain, P1 form
RCSB PDB - 6WZO: Structure of SARS-CoV-2 Nucleocapsid dimerization domain, P1 form (rcsb.org)
Frontiers | Nrf2 Negatively Regulates Type I Interferon Responses and Increases Susceptibility to Herpes Genital Infection in...
Frontiers | Nrf2 Negatively Regulates Type I Interferon Responses and Increases Susceptibility to Herpes Genital Infection in... (frontiersin.org)
Frontiers | Molecular Bases of VEGFR-2-Mediated Physiological Function and Pathological Role | Cell and Developmental Biology
Frontiers | Molecular Bases of VEGFR-2-Mediated Physiological Function and Pathological Role | Cell and Developmental Biology (frontiersin.org)
Genome-Wide Classification and Evolutionary Analysis of the bHLH Family of Transcription Factors in Arabidopsis, Poplar, Rice,...
Genome-Wide Classification and Evolutionary Analysis of the bHLH Family of Transcription Factors in Arabidopsis, Poplar, Rice,... (plantphysiol.org)
The Arabidopsis Basic/Helix-Loop-Helix Transcription Factor Family | Plant Cell
The Arabidopsis Basic/Helix-Loop-Helix Transcription Factor Family | Plant Cell (plantcell.org)
Activation of the p53 pathway by small-molecule-induced MDM2 and MDMX dimerization | PNAS
Activation of the p53 pathway by small-molecule-induced MDM2 and MDMX dimerization | PNAS (pnas.org)
Georgios Kontogeorgis - DTU
Georgios Kontogeorgis - DTU (dtu.dk)
A novel self-promoted Morita-Baylis-Hillman-like dimerization | SpringerLink
A novel self-promoted Morita-Baylis-Hillman-like dimerization | SpringerLink (link.springer.com)
Highlights from Recent Cancer Literature | Cancer Research
Highlights from Recent Cancer Literature | Cancer Research (cancerres.aacrjournals.org)
Plus it
Plus it (plantphysiol.org)
GPCR Molecular Pharmacology and Drug Targeting: Shifting Paradigms and New Directions | Drug Discovery & Development |...
GPCR Molecular Pharmacology and Drug Targeting: Shifting Paradigms and New Directions | Drug Discovery & Development |... (wiley.com)
The histone fold: a ubiquitous architectural motif utilized in DNA compaction and protein dimerization | PNAS
The histone fold: a ubiquitous architectural motif utilized in DNA compaction and protein dimerization | PNAS (pnas.org)
Dimerization of a specific DNA-binding protein on the DNA | Science
Dimerization of a specific DNA-binding protein on the DNA | Science (science.sciencemag.org)
IUCr) Acta Crystallographica Section F Volume 73, Part 3, March 2017
IUCr) Acta Crystallographica Section F Volume 73, Part 3, March 2017 (journals.iucr.org)
Mechanisms in Transcriptional Regulation | Molecular Biology (Life Sciences) | Cell & Molecular Biology | Life Sciences |...
Mechanisms in Transcriptional Regulation | Molecular Biology (Life Sciences) | Cell & Molecular Biology | Life Sciences |... (wiley.com)
Applied Petrochemical Research - a SpringerOpen journal (Societies)
Applied Petrochemical Research - a SpringerOpen journal (Societies) (springer.com)