Cyclin B1: A cyclin B subtype that colocalizes with MICROTUBULES during INTERPHASE and is transported into the CELL NUCLEUS at the end of the G2 PHASE.Cyclin B: A cyclin subtype that is transported into the CELL NUCLEUS at the end of the G2 PHASE. It stimulates the G2/M phase transition by activating CDC2 PROTEIN KINASE.Cyclin D1: Protein encoded by the bcl-1 gene which plays a critical role in regulating the cell cycle. Overexpression of cyclin D1 is the result of bcl-1 rearrangement, a t(11;14) translocation, and is implicated in various neoplasms.Cyclin A: A cyclin subtype that has specificity for CDC2 PROTEIN KINASE and CYCLIN-DEPENDENT KINASE 2. It plays a role in progression of the CELL CYCLE through G1/S and G2/M phase transitions.Cyclin E: A 50-kDa protein that complexes with CYCLIN-DEPENDENT KINASE 2 in the late G1 phase of the cell cycle.CDC2 Protein Kinase: Phosphoprotein with protein kinase activity that functions in the G2/M phase transition of the CELL CYCLE. It is the catalytic subunit of the MATURATION-PROMOTING FACTOR and complexes with both CYCLIN A and CYCLIN B in mammalian cells. The maximal activity of cyclin-dependent kinase 1 is achieved when it is fully dephosphorylated.Cyclin A1: A cyclin A subtype primarily found in male GERM CELLS. It may play a role in the passage of SPERMATOCYTES into meiosis I.Cyclin D2: A cyclin D subtype which is regulated by GATA4 TRANSCRIPTION FACTOR. Experiments using KNOCKOUT MICE suggest a role for cyclin D2 in granulosa cell proliferation and gonadal development.Cyclin D3: A broadly expressed type D cyclin. Experiments using KNOCKOUT MICE suggest a role for cyclin D3 in LYMPHOCYTE development.Cyclin A2: A widely-expressed cyclin A subtype that functions during the G1/S and G2/M transitions of the CELL CYCLE.Cyclins: A large family of regulatory proteins that function as accessory subunits to a variety of CYCLIN-DEPENDENT KINASES. They generally function as ENZYME ACTIVATORS that drive the CELL CYCLE through transitions between phases. A subset of cyclins may also function as transcriptional regulators.Cyclin D: A cyclin subtype that is specific for CYCLIN-DEPENDENT KINASE 4 and CYCLIN-DEPENDENT KINASE 6. Unlike most cyclins, cyclin D expression is not cyclical, but rather it is expressed in response to proliferative signals. Cyclin D may therefore play a role in cellular responses to mitogenic signals.Phosphorylation: The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.Mitosis: A type of CELL NUCLEUS division by means of which the two daughter nuclei normally receive identical complements of the number of CHROMOSOMES of the somatic cells of the species.Cyclin-Dependent Kinases: Protein kinases that control cell cycle progression in all eukaryotes and require physical association with CYCLINS to achieve full enzymatic activity. Cyclin-dependent kinases are regulated by phosphorylation and dephosphorylation events.Cell Cycle: The complex series of phenomena, occurring between the end of one CELL DIVISION and the end of the next, by which cellular material is duplicated and then divided between two daughter cells. The cell cycle includes INTERPHASE, which includes G0 PHASE; G1 PHASE; S PHASE; and G2 PHASE, and CELL DIVISION PHASE.Cyclin G1: A cyclin G subtype that is constitutively expressed throughout the cell cycle. Cyclin G1 is considered a major transcriptional target of TUMOR SUPPRESSOR PROTEIN P53 and is highly induced in response to DNA damage.Cyclin G: A cyclin subtype that is found associated with CYCLIN-DEPENDENT KINASE 5; cyclin G associated kinase, and PROTEIN PHOSPHATASE 2.Protein-Serine-Threonine Kinases: A group of enzymes that catalyzes the phosphorylation of serine or threonine residues in proteins, with ATP or other nucleotides as phosphate donors.G2 Phase: The period of the CELL CYCLE following DNA synthesis (S PHASE) and preceding M PHASE (cell division phase). The CHROMOSOMES are tetraploid in this point.Cell Cycle Proteins: Proteins that control the CELL DIVISION CYCLE. This family of proteins includes a wide variety of classes, including CYCLIN-DEPENDENT KINASES, mitogen-activated kinases, CYCLINS, and PHOSPHOPROTEIN PHOSPHATASES as well as their putative substrates such as chromatin-associated proteins, CYTOSKELETAL PROTEINS, and TRANSCRIPTION FACTORS.Protein Kinases: A family of enzymes that catalyze the conversion of ATP and a protein to ADP and a phosphoprotein.Cyclin-Dependent Kinase 2: A key regulator of CELL CYCLE progression. It partners with CYCLIN E to regulate entry into S PHASE and also interacts with CYCLIN A to phosphorylate RETINOBLASTOMA PROTEIN. Its activity is inhibited by CYCLIN-DEPENDENT KINASE INHIBITOR P27 and CYCLIN-DEPENDENT KINASE INHIBITOR P21.Cyclin C: A cyclin subtype that binds to the CYCLIN-DEPENDENT KINASE 3 and CYCLIN-DEPENDENT KINASE 8. Cyclin C plays a dual role as a transcriptional regulator and a G1 phase CELL CYCLE regulator.Cyclin B2: A cyclin B subtype that colocalizes with GOLGI APPARATUS during INTERPHASE and is transported into the CELL NUCLEUS at the end of the G2 PHASE.CDC2-CDC28 Kinases: A family of cell cycle-dependent kinases that are related in structure to CDC28 PROTEIN KINASE; S CEREVISIAE; and the CDC2 PROTEIN KINASE found in mammalian species.cdc25 Phosphatases: A subclass of dual specificity phosphatases that play a role in the progression of the CELL CYCLE. They dephosphorylate and activate CYCLIN-DEPENDENT KINASES.Cyclin T: A cyclin subtype that is found associated with CYCLIN-DEPENDENT KINASE 9. Unlike traditional cyclins, which regulate the CELL CYCLE, type T cyclins appear to regulate transcription and are components of positive transcriptional elongation factor B.Maturation-Promoting Factor: Protein kinase that drives both the mitotic and meiotic cycles in all eukaryotic organisms. In meiosis it induces immature oocytes to undergo meiotic maturation. In mitosis it has a role in the G2/M phase transition. Once activated by CYCLINS; MPF directly phosphorylates some of the proteins involved in nuclear envelope breakdown, chromosome condensation, spindle assembly, and the degradation of cyclins. The catalytic subunit of MPF is PROTEIN P34CDC2.Cyclin H: A cyclin subtype that is found as a component of a heterotrimeric complex containing cyclin-dependent kinase 7 and CDK-activating kinase assembly factor. The complex plays a role in cellular proliferation by phosphorylating several CYCLIN DEPENDENT KINASES at specific regulatory threonine sites.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.Cyclin-Dependent Kinase 4: Cyclin-dependent kinase 4 is a key regulator of G1 PHASE of the CELL CYCLE. It partners with CYCLIN D to phosphorylate RETINOBLASTOMA PROTEIN. CDK4 activity is inhibited by CYCLIN-DEPENDENT KINASE INHIBITOR P16.G1 Phase: The period of the CELL CYCLE preceding DNA REPLICATION in S PHASE. Subphases of G1 include "competence" (to respond to growth factors), G1a (entry into G1), G1b (progression), and G1c (assembly). Progression through the G1 subphases is effected by limiting growth factors, nutrients, or inhibitors.S Phase: Phase of the CELL CYCLE following G1 and preceding G2 when the entire DNA content of the nucleus is replicated. It is achieved by bidirectional replication at multiple sites along each chromosome.Cyclin G2: An unusual cyclin subtype that is found highly expressed in terminally differentiated cells. Unlike conventional cyclins increased expression of cyclin G2 is believed to cause a withdrawal of cells from the CELL CYCLE.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.Serine: A non-essential amino acid occurring in natural form as the L-isomer. It is synthesized from GLYCINE or THREONINE. It is involved in the biosynthesis of PURINES; PYRIMIDINES; and other amino acids.Starfish: Echinoderms having bodies of usually five radially disposed arms coalescing at the center.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.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.Oocytes: Female germ cells derived from OOGONIA and termed OOCYTES when they enter MEIOSIS. The primary oocytes begin meiosis but are arrested at the diplotene state until OVULATION at PUBERTY to give rise to haploid secondary oocytes or ova (OVUM).Protamine Kinase: An aspect of protein kinase (EC 22.214.171.124) in which serine residues in protamines and histones are phosphorylated in the presence of ATP.Cell Line: Established cell cultures that have the potential to propagate indefinitely.Cyclin-Dependent Kinase Inhibitor p27: A cyclin-dependent kinase inhibitor that coordinates the activation of CYCLIN and CYCLIN-DEPENDENT KINASES during the CELL CYCLE. It interacts with active CYCLIN D complexed to CYCLIN-DEPENDENT KINASE 4 in proliferating cells, while in arrested cells it binds and inhibits CYCLIN E complexed to CYCLIN-DEPENDENT KINASE 2.Retinoblastoma Protein: Product of the retinoblastoma tumor suppressor gene. It is a nuclear phosphoprotein hypothesized to normally act as an inhibitor of cell proliferation. Rb protein is absent in retinoblastoma cell lines. It also has been shown to form complexes with the adenovirus E1A protein, the SV40 T antigen, and the human papilloma virus E7 protein.Threonine: An essential amino acid occurring naturally in the L-form, which is the active form. It is found in eggs, milk, gelatin, and other proteins.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.Cell Division: The fission of a CELL. It includes CYTOKINESIS, when the CYTOPLASM of a cell is divided, and CELL NUCLEUS DIVISION.Substrate Specificity: A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.Ubiquitin-Protein Ligase Complexes: Complexes of enzymes that catalyze the covalent attachment of UBIQUITIN to other proteins by forming a peptide bond between the C-terminal GLYCINE of UBIQUITIN and the alpha-amino groups of LYSINE residues in the protein. The complexes play an important role in mediating the selective-degradation of short-lived and abnormal proteins. The complex of enzymes can be broken down into three components that involve activation of ubiquitin (UBIQUITIN-ACTIVATING ENZYMES), conjugation of ubiquitin to the ligase complex (UBIQUITIN-CONJUGATING ENZYMES), and ligation of ubiquitin to the substrate protein (UBIQUITIN-PROTEIN LIGASES).Meiosis: A type of CELL NUCLEUS division, occurring during maturation of the GERM CELLS. Two successive cell nucleus divisions following a single chromosome duplication (S PHASE) result in daughter cells with half the number of CHROMOSOMES as the parent cells.Cell 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)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.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.Proto-Oncogene Proteins c-mos: Cellular proteins encoded by the c-mos genes (GENES, MOS). They function in the cell cycle to maintain MATURATION PROMOTING FACTOR in the active state and have protein-serine/threonine kinase activity. Oncogenic transformation can take place when c-mos proteins are expressed at the wrong time.Xenopus: An aquatic genus of the family, Pipidae, occurring in Africa and distinguished by having black horny claws on three inner hind toes.Protein-Tyrosine Kinases: Protein kinases that catalyze the PHOSPHORYLATION of TYROSINE residues in proteins with ATP or other nucleotides as phosphate donors.Xenopus Proteins: Proteins obtained from various species of Xenopus. Included here are proteins from the African clawed frog (XENOPUS LAEVIS). Many of these proteins have been the subject of scientific investigations in the area of MORPHOGENESIS and development.Cell Line, Tumor: A cell line derived from cultured tumor cells.Cyclin-Dependent Kinase Inhibitor p21: A cyclin-dependent kinase inhibitor that mediates TUMOR SUPPRESSOR PROTEIN P53-dependent CELL CYCLE arrest. p21 interacts with a range of CYCLIN-DEPENDENT KINASES and associates with PROLIFERATING CELL NUCLEAR ANTIGEN and CASPASE 3.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.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.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.Metaphase: The phase of cell nucleus division following PROMETAPHASE, in which the CHROMOSOMES line up across the equatorial plane of the SPINDLE APPARATUS prior to separation.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.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.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.Cell Proliferation: All of the processes involved in increasing CELL NUMBER including CELL DIVISION.Cyclin I: A cyclin subtype that is found abundantly in post-mitotic tissues. In contrast to the classical cyclins, its level does not fluctuate during the cell cycle.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.Prometaphase: The phase of cell nucleus division following PROPHASE, when the breakdown of the NUCLEAR ENVELOPE occurs and the MITOTIC SPINDLE APPARATUS enters the nuclear region and attaches to the KINETOCHORES.Calcium-Calmodulin-Dependent Protein Kinases: A CALMODULIN-dependent enzyme that catalyzes the phosphorylation of proteins. This enzyme is also sometimes dependent on CALCIUM. A wide range of proteins can act as acceptor, including VIMENTIN; SYNAPSINS; GLYCOGEN SYNTHASE; MYOSIN LIGHT CHAINS; and the MICROTUBULE-ASSOCIATED PROTEINS. (From Enzyme Nomenclature, 1992, p277)Nocodazole: Nocodazole is an antineoplastic agent which exerts its effect by depolymerizing microtubules.Tumor Suppressor Proteins: Proteins that are normally involved in holding cellular growth in check. Deficiencies or abnormalities in these proteins may lead to unregulated cell growth and tumor development.Phosphoserine: The phosphoric acid ester of serine.Anaphase-Promoting Complex-Cyclosome: An E3 ubiquitin ligase primarily involved in regulation of the metaphase-to-anaphase transition during MITOSIS through ubiquitination of specific CELL CYCLE PROTEINS. Enzyme activity is tightly regulated through subunits and cofactors, which modulate activation, inhibition, and substrate specificity. The anaphase-promoting complex, or APC-C, is also involved in tissue differentiation in the PLACENTA, CRYSTALLINE LENS, and SKELETAL MUSCLE, and in regulation of postmitotic NEURONAL PLASTICITY and excitability.Recombinant Proteins: Proteins prepared by recombinant DNA technology.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.Anaphase: The phase of cell nucleus division following METAPHASE, in which the CHROMATIDS separate and migrate to opposite poles of the spindle.Securin: Securin is involved in the control of the metaphase-anaphase transition during MITOSIS. It promotes the onset of anaphase by blocking SEPARASE function and preventing proteolysis of cohesin and separation of sister CHROMATIDS. Overexpression of securin is associated with NEOPLASTIC CELL TRANSFORMATION and tumor formation.Oncogene Proteins: Proteins coded by oncogenes. They include proteins resulting from the fusion of an oncogene and another gene (ONCOGENE PROTEINS, FUSION).Spindle Apparatus: A microtubule structure that forms during CELL DIVISION. It consists of two SPINDLE POLES, and sets of MICROTUBULES that may include the astral microtubules, the polar microtubules, and the kinetochore microtubules.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.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.Transcription Factors: Endogenous substances, usually proteins, which are effective in the initiation, stimulation, or termination of the genetic transcription process.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.Cyclin-Dependent Kinase 6: Cyclin-dependent kinase 6 associates with CYCLIN D and phosphorylates RETINOBLASTOMA PROTEIN during G1 PHASE of the CELL CYCLE. It helps regulate the transition to S PHASE and its kinase activity is inhibited by CYCLIN-DEPENDENT KINASE INHIBITOR P18.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.Enzyme Inhibitors: Compounds or agents that combine with an enzyme in such a manner as to prevent the normal substrate-enzyme combination and the catalytic reaction.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.Phosphothreonine: The phosphoric acid ester of threonine. Used as an identifier in the analysis of peptides, proteins, and enzymes.Xenopus laevis: The commonest and widest ranging species of the clawed "frog" (Xenopus) in Africa. This species is used extensively in research. There is now a significant population in California derived from escaped laboratory animals.PhosphopeptidesPhosphoproteinsCdh1 Proteins: Cdh1 is an activator of the anaphase-promoting complex-cyclosome, and is involved in substrate recognition. It associates with the complex in late MITOSIS from anaphase through G1 to regulate activity of CYCLIN-DEPENDENT KINASES and to prevent premature DNA replication.Peptide Mapping: Analysis of PEPTIDES that are generated from the digestion or fragmentation of a protein or mixture of PROTEINS, by ELECTROPHORESIS; CHROMATOGRAPHY; or MASS SPECTROMETRY. The resulting peptide fingerprints are analyzed for a variety of purposes including the identification of the proteins in a sample, GENETIC POLYMORPHISMS, patterns of gene expression, and patterns diagnostic for diseases.Microtubule-Associated Proteins: High molecular weight proteins found in the MICROTUBULES of the cytoskeletal system. Under certain conditions they are required for TUBULIN assembly into the microtubules and stabilize the assembled microtubules.Genes, bcl-1: The B-cell leukemia/lymphoma-1 genes, associated with various neoplasms when overexpressed. Overexpression results from the t(11;14) translocation, which is characteristic of mantle zone-derived B-cell lymphomas. The human c-bcl-1 gene is located at 11q13 on the long arm of chromosome 11.Mitogen-Activated Protein Kinases: A superfamily of PROTEIN-SERINE-THREONINE KINASES that are activated by diverse stimuli via protein kinase cascades. They are the final components of the cascades, activated by phosphorylation by MITOGEN-ACTIVATED PROTEIN KINASE KINASES, which in turn are activated by mitogen-activated protein kinase kinase kinases (MAP KINASE KINASE KINASES).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.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)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.Kinetics: The rate dynamics in chemical or physical systems.Tyrosine: A non-essential amino acid. In animals it is synthesized from PHENYLALANINE. It is also the precursor of EPINEPHRINE; THYROID HORMONES; and melanin.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.Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.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.RNA, Small Interfering: Small double-stranded, non-protein coding RNAs (21-31 nucleotides) involved in GENE SILENCING functions, especially RNA INTERFERENCE (RNAi). Endogenously, siRNAs are generated from dsRNAs (RNA, DOUBLE-STRANDED) by the same ribonuclease, Dicer, that generates miRNAs (MICRORNAS). The perfect match of the siRNAs' antisense strand to their target RNAs mediates RNAi by siRNA-guided RNA cleavage. siRNAs fall into different classes including trans-acting siRNA (tasiRNA), repeat-associated RNA (rasiRNA), small-scan RNA (scnRNA), and Piwi protein-interacting RNA (piRNA) and have different specific gene silencing functions.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.Centrosome: The cell center, consisting of a pair of CENTRIOLES surrounded by a cloud of amorphous material called the pericentriolar region. During interphase, the centrosome nucleates microtubule outgrowth. The centrosome duplicates and, during mitosis, separates to form the two poles of the mitotic spindle (MITOTIC SPINDLE APPARATUS).Cell Extracts: Preparations of cell constituents or subcellular materials, isolates, or substances.Immunoblotting: Immunologic method used for detecting or quantifying immunoreactive substances. The substance is identified by first immobilizing it by blotting onto a membrane and then tagging it with labeled antibodies.Promoter Regions, Genetic: DNA sequences which are recognized (directly or indirectly) and bound by a DNA-dependent RNA polymerase during the initiation of transcription. Highly conserved sequences within the promoter include the Pribnow box in bacteria and the TATA BOX in eukaryotes.Interphase: The interval between two successive CELL DIVISIONS during which the CHROMOSOMES are not individually distinguishable. It is composed of the G phases (G1 PHASE; G0 PHASE; G2 PHASE) and S PHASE (when DNA replication occurs).Down-Regulation: A negative regulatory effect on physiological processes at the molecular, cellular, or systemic level. At the molecular level, the major regulatory sites include membrane receptors, genes (GENE EXPRESSION REGULATION), mRNAs (RNA, MESSENGER), and proteins.Cdc20 Proteins: Highly conserved proteins that specifically bind to and activate the anaphase-promoting complex-cyclosome, promoting ubiquitination and proteolysis of cell-cycle-regulatory proteins. Cdc20 is essential for anaphase-promoting complex activity, initiation of anaphase, and cyclin proteolysis during mitosis.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.Phosphoprotein Phosphatases: A group of enzymes removing the SERINE- or THREONINE-bound phosphate groups from a wide range of phosphoproteins, including a number of enzymes which have been phosphorylated under the action of a kinase. (Enzyme Nomenclature, 1992)Intracellular Signaling Peptides and Proteins: Proteins and peptides that are involved in SIGNAL TRANSDUCTION within the cell. Included here are peptides and proteins that regulate the activity of TRANSCRIPTION FACTORS and cellular processes in response to signals from CELL SURFACE RECEPTORS. Intracellular signaling peptide and proteins may be part of an enzymatic signaling cascade or act through binding to and modifying the action of other signaling factors.CDC28 Protein Kinase, S cerevisiae: A protein kinase encoded by the Saccharomyces cerevisiae CDC28 gene and required for progression from the G1 PHASE to the S PHASE in the CELL CYCLE.Glycogen Synthase Kinase 3: A glycogen synthase kinase that was originally described as a key enzyme involved in glycogen metabolism. It regulates a diverse array of functions such as CELL DIVISION, microtubule function and APOPTOSIS.Time Factors: Elements of limited time intervals, contributing to particular results or situations.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.Prophase: The first phase of cell nucleus division, in which the CHROMOSOMES become visible, the CELL NUCLEUS starts to lose its identity, the SPINDLE APPARATUS appears, and the CENTRIOLES migrate toward opposite poles.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.Okadaic Acid: A specific inhibitor of phosphoserine/threonine protein phosphatase 1 and 2a. It is also a potent tumor promoter. (Thromb Res 1992;67(4):345-54 & Cancer Res 1993;53(2):239-41)Casein Kinases: A group of protein-serine-threonine kinases that was originally identified as being responsible for the PHOSPHORYLATION of CASEINS. They are ubiquitous enzymes that have a preference for acidic proteins. Casein kinases play a role in SIGNAL TRANSDUCTION by phosphorylating a variety of regulatory cytoplasmic and regulatory nuclear proteins.Immunohistochemistry: Histochemical localization of immunoreactive substances using labeled antibodies as reagents.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).)E2F Transcription Factors: A family of basic helix-loop-helix transcription factors that control expression of a variety of GENES involved in CELL CYCLE regulation. E2F transcription factors typically form heterodimeric complexes with TRANSCRIPTION FACTOR DP1 or transcription factor DP2, and they have N-terminal DNA binding and dimerization domains. E2F transcription factors can act as mediators of transcriptional repression or transcriptional activation.Ovum: A mature haploid female germ cell extruded from the OVARY at OVULATION.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.Fibroblasts: Connective tissue cells which secrete an extracellular matrix rich in collagen and other macromolecules.Carrier Proteins: Transport proteins that carry specific substances in the blood or across cell membranes.RNA Interference: A gene silencing phenomenon whereby specific dsRNAs (RNA, DOUBLE-STRANDED) trigger the degradation of homologous mRNA (RNA, MESSENGER). The specific dsRNAs are processed into SMALL INTERFERING RNA (siRNA) which serves as a guide for cleavage of the homologous mRNA in the RNA-INDUCED SILENCING COMPLEX. DNA METHYLATION may also be triggered during this process.F-Box Proteins: A family of proteins that share the F-BOX MOTIF and are involved in protein-protein interactions. They play an important role in process of protein ubiquition by associating with a variety of substrates and then associating into SCF UBIQUITIN LIGASE complexes. They are held in the ubiquitin-ligase complex via binding to SKP DOMAIN PROTEINS.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.Cyclin-Dependent Kinase 9: A multifunctional CDC2 kinase-related kinase that plays roles in transcriptional elongation, CELL DIFFERENTIATION, and APOPTOSIS. It is found associated with CYCLIN T and is a component of POSITIVE TRANSCRIPTIONAL ELONGATION FACTOR B.DNA Damage: Injuries to DNA that introduce deviations from its normal, intact structure and which may, if left unrepaired, result in a MUTATION or a block of DNA REPLICATION. These deviations may be caused by physical or chemical agents and occur by natural or unnatural, introduced circumstances. They include the introduction of illegitimate bases during replication or by deamination or other modification of bases; the loss of a base from the DNA backbone leaving an abasic site; single-strand breaks; double strand breaks; and intrastrand (PYRIMIDINE DIMERS) or interstrand crosslinking. Damage can often be repaired (DNA REPAIR). If the damage is extensive, it can induce APOPTOSIS.Cell Cycle Checkpoints: Regulatory signaling systems that control the progression through the CELL CYCLE. They ensure that the cell has completed, in the correct order and without mistakes, all the processes required to replicate the GENOME and CYTOPLASM, and divide them equally between two daughter cells. If cells sense they have not completed these processes or that the environment does not have the nutrients and growth hormones in place to proceed, then the cells are restrained (or "arrested") until the processes are completed and growth conditions are suitable.Cyclic AMP-Dependent Protein Kinases: A group of enzymes that are dependent on CYCLIC AMP and catalyze the phosphorylation of SERINE or THREONINE residues on proteins. Included under this category are two cyclic-AMP-dependent protein kinase subtypes, each of which is defined by its subunit composition.Protein Kinase C: An serine-threonine protein kinase that requires the presence of physiological concentrations of CALCIUM and membrane PHOSPHOLIPIDS. The additional presence of DIACYLGLYCEROLS markedly increases its sensitivity to both calcium and phospholipids. The sensitivity of the enzyme can also be increased by PHORBOL ESTERS and it is believed that protein kinase C is the receptor protein of tumor-promoting phorbol esters.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.Purines: A series of heterocyclic compounds that are variously substituted in nature and are known also as purine bases. They include ADENINE and GUANINE, constituents of nucleic acids, as well as many alkaloids such as CAFFEINE and THEOPHYLLINE. Uric acid is the metabolic end product of purine metabolism.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.DNA Replication: The process by which a DNA molecule is duplicated.NIH 3T3 Cells: A continuous cell line of high contact-inhibition established from NIH Swiss mouse embryo cultures. The cells are useful for DNA transfection and transformation studies. (From ATCC [Internet]. Virginia: American Type Culture Collection; c2002 [cited 2002 Sept 26]. Available from http://www.atcc.org/)Histones: Small chromosomal proteins (approx 12-20 kD) possessing an open, unfolded structure and attached to the DNA in cell nuclei by ionic linkages. Classification into the various types (designated histone I, histone II, etc.) is based on the relative amounts of arginine and lysine in each.Proteasome Endopeptidase Complex: A large multisubunit complex that plays an important role in the degradation of most of the cytosolic and nuclear proteins in eukaryotic cells. It contains a 700-kDa catalytic sub-complex and two 700-kDa regulatory sub-complexes. The complex digests ubiquitinated proteins and protein activated via ornithine decarboxylase antizyme.Cyclin-Dependent Kinase 5: A serine-threonine kinase that plays important roles in CELL DIFFERENTIATION; CELL MIGRATION; and CELL DEATH of NERVE CELLS. It is closely related to other CYCLIN-DEPENDENT KINASES but does not seem to participate in CELL CYCLE regulation.Mitogen-Activated Protein Kinase Kinases: A serine-threonine protein kinase family whose members are components in protein kinase cascades activated by diverse stimuli. These MAPK kinases phosphorylate MITOGEN-ACTIVATED PROTEIN KINASES and are themselves phosphorylated by MAP KINASE KINASE KINASES. JNK kinases (also known as SAPK kinases) are a subfamily.E2F1 Transcription Factor: An E2F transcription factor that interacts directly with RETINOBLASTOMA PROTEIN and CYCLIN A and activates GENETIC TRANSCRIPTION required for CELL CYCLE entry and DNA synthesis. E2F1 is involved in DNA REPAIR and APOPTOSIS.Proliferating Cell Nuclear Antigen: Nuclear antigen with a role in DNA synthesis, DNA repair, and cell cycle progression. PCNA is required for the coordinated synthesis of both leading and lagging strands at the replication fork during DNA replication. PCNA expression correlates with the proliferation activity of several malignant and non-malignant cell types.G2 Phase Cell Cycle Checkpoints: CELL CYCLE regulatory signaling systems that are triggered by DNA DAMAGE or lack of nutrients during G2 PHASE. When triggered they restrain cells transitioning from G2 phase to M PHASE.Proteins: Linear POLYPEPTIDES that are synthesized on RIBOSOMES and may be further modified, crosslinked, cleaved, or assembled into complex proteins with several subunits. The specific sequence of AMINO ACIDS determines the shape the polypeptide will take, during PROTEIN FOLDING, and the function of the protein.Embryo, Nonmammalian: The developmental entity of a fertilized egg (ZYGOTE) in animal species other than MAMMALS. For chickens, use CHICK EMBRYO.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.Mitogen-Activated Protein Kinase 1: A proline-directed serine/threonine protein kinase which mediates signal transduction from the cell surface to the nucleus. Activation of the enzyme by phosphorylation leads to its translocation into the nucleus where it acts upon specific transcription factors. p40 MAPK and p41 MAPK are isoforms.Mutagenesis, Site-Directed: Genetically engineered MUTAGENESIS at a specific site in the DNA molecule that introduces a base substitution, or an insertion or deletion.Casein Kinase II: A ubiquitous casein kinase that is comprised of two distinct catalytic subunits and dimeric regulatory subunit. Casein kinase II has been shown to phosphorylate a large number of substrates, many of which are proteins involved in the regulation of gene expression.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.Phosphotransferases: A rather large group of enzymes comprising not only those transferring phosphate but also diphosphate, nucleotidyl residues, and others. These have also been subdivided according to the acceptor group. (From Enzyme Nomenclature, 1992) EC 2.7.MAP Kinase Signaling System: An intracellular signaling system involving the MAP kinase cascades (three-membered protein kinase cascades). Various upstream activators, which act in response to extracellular stimuli, trigger the cascades by activating the first member of a cascade, MAP KINASE KINASE KINASES; (MAPKKKs). Activated MAPKKKs phosphorylate MITOGEN-ACTIVATED PROTEIN KINASE KINASES which in turn phosphorylate the MITOGEN-ACTIVATED PROTEIN KINASES; (MAPKs). The MAPKs then act on various downstream targets to affect gene expression. In mammals, there are several distinct MAP kinase pathways including the ERK (extracellular signal-regulated kinase) pathway, the SAPK/JNK (stress-activated protein kinase/c-jun kinase) pathway, and the p38 kinase pathway. There is some sharing of components among the pathways depending on which stimulus originates activation of the cascade.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.Gene Expression: The phenotypic manifestation of a gene or genes by the processes of GENETIC TRANSCRIPTION and GENETIC TRANSLATION.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.Active Transport, Cell Nucleus: Gated transport mechanisms by which proteins or RNA are moved across the NUCLEAR MEMBRANE.Microtubules: Slender, cylindrical filaments found in the cytoskeleton of plant and animal cells. They are composed of the protein TUBULIN and are influenced by TUBULIN MODULATORS.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.Protein Biosynthesis: The biosynthesis of PEPTIDES and PROTEINS on RIBOSOMES, directed by MESSENGER RNA, via TRANSFER RNA that is charged with standard proteinogenic AMINO ACIDS.Ribosomal Protein S6 Kinases, 90-kDa: A family of ribosomal protein S6 kinases that are structurally distinguished from RIBOSOMAL PROTEIN S6 KINASES, 70-KDA by their apparent molecular size and the fact they contain two functional kinase domains. Although considered RIBOSOMAL PROTEIN S6 KINASES, members of this family are activated via the MAP KINASE SIGNALING SYSTEM and have been shown to act on a diverse array of substrates that are involved in cellular regulation such as RIBOSOMAL PROTEIN S6 and CAMP RESPONSE ELEMENT-BINDING PROTEIN.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.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.Transcriptional Activation: Processes that stimulate the GENETIC TRANSCRIPTION of a gene or set of genes.CCAAT-Binding Factor: A heterotrimeric DNA-binding protein that binds to CCAAT motifs in the promoters of eukaryotic genes. It is composed of three subunits: A, B and C.Oogenesis: The process of germ cell development in the female from the primordial germ cells through OOGONIA to the mature haploid ova (OVUM).Apc3 Subunit, Anaphase-Promoting Complex-Cyclosome: A highly evolutionarily conserved subunit of the anaphase-promoting complex (APC-C) containing multiple 34-amino-acid tetratricopeptide repeats. These domains, also found in Apc subunits 6, 7, and 8, have been shown to mediate protein-protein interactions, suggesting that Apc3 may assist in coordinating the juxtaposition of the catalytic and substrate recognition module subunits relative to co-activators and APC-C inhibitors.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).Reverse Transcriptase Polymerase Chain Reaction: A variation of the PCR technique in which cDNA is made from RNA via reverse transcription. The resultant cDNA is then amplified using standard PCR protocols.Genes, cdc: Genes that code for proteins that regulate the CELL DIVISION CYCLE. These genes form a regulatory network that culminates in the onset of MITOSIS by activating the p34cdc2 protein (PROTEIN P34CDC2).Trans-Activators: Diffusible gene products that act on homologous or heterologous molecules of viral or cellular DNA to regulate the expression of proteins.Cyclin-Dependent Kinase Inhibitor p16: A product of the p16 tumor suppressor gene (GENES, P16). It is also called INK4 or INK4A because it is the prototype member of the INK4 CYCLIN-DEPENDENT KINASE INHIBITORS. This protein is produced from the alpha mRNA transcript of the p16 gene. The other gene product, produced from the alternatively spliced beta transcript, is TUMOR SUPPRESSOR PROTEIN P14ARF. Both p16 gene products have tumor suppressor functions.G0 Phase: A quiescent state of cells during G1 PHASE.Aurora Kinases: A family of highly conserved serine-threonine kinases that are involved in the regulation of MITOSIS. They are involved in many aspects of cell division, including centrosome duplication, SPINDLE APPARATUS formation, chromosome alignment, attachment to the spindle, checkpoint activation, and CYTOKINESIS.G-Protein-Coupled Receptor Kinase 5: A G-protein-coupled receptor kinase subtype that is primarily expressed in the MYOCARDIUM and may play a role in the regulation of cardiac functions.Proto-Oncogene Proteins c-akt: A protein-serine-threonine kinase that is activated by PHOSPHORYLATION in response to GROWTH FACTORS or INSULIN. It plays a major role in cell metabolism, growth, and survival as a core component of SIGNAL TRANSDUCTION. Three isoforms have been described in mammalian cells.src-Family Kinases: A PROTEIN-TYROSINE KINASE family that was originally identified by homology to the Rous sarcoma virus ONCOGENE PROTEIN PP60(V-SRC). They interact with a variety of cell-surface receptors and participate in intracellular signal transduction pathways. Oncogenic forms of src-family kinases can occur through altered regulation or expression of the endogenous protein and by virally encoded src (v-src) genes.Phosphotransferases (Alcohol Group Acceptor): A group of enzymes that transfers a phosphate group onto an alcohol group acceptor. EC 2.7.1.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.Mad2 Proteins: Mad2 is a component of the spindle-assembly checkpoint apparatus. It binds to and inhibits the Cdc20 activator subunit of the anaphase-promoting complex, preventing the onset of anaphase until all chromosomes are properly aligned at the metaphase plate. Mad2 is required for proper microtubule capture at KINETOCHORES.Microinjections: The injection of very small amounts of fluid, often with the aid of a microscope and microsyringes.Phosphatidylinositol 3-Kinases: Phosphotransferases that catalyzes the conversion of 1-phosphatidylinositol to 1-phosphatidylinositol 3-phosphate. Many members of this enzyme class are involved in RECEPTOR MEDIATED SIGNAL TRANSDUCTION and regulation of vesicular transport with the cell. Phosphatidylinositol 3-Kinases have been classified both according to their substrate specificity and their mode of action within the cell.Polyploidy: The chromosomal constitution of a cell containing multiples of the normal number of CHROMOSOMES; includes triploidy (symbol: 3N), tetraploidy (symbol: 4N), etc.Protein Kinase Inhibitors: Agents that inhibit PROTEIN KINASES.Isoenzymes: Structurally related forms of an enzyme. Each isoenzyme has the same mechanism and classification, but differs in its chemical, physical, or immunological characteristics.Ubiquitin: A highly conserved 76-amino acid peptide universally found in eukaryotic cells that functions as a marker for intracellular PROTEIN TRANSPORT and degradation. Ubiquitin becomes activated through a series of complicated steps and forms an isopeptide bond to lysine residues of specific proteins within the cell. These "ubiquitinated" proteins can be recognized and degraded by proteosomes or be transported to specific compartments within the cell.Ubiquitin-Protein Ligases: A diverse class of enzymes that interact with UBIQUITIN-CONJUGATING ENZYMES and ubiquitination-specific protein substrates. Each member of this enzyme group has its own distinct specificity for a substrate and ubiquitin-conjugating enzyme. Ubiquitin-protein ligases exist as both monomeric proteins multiprotein complexes.Neoplasm Proteins: Proteins whose abnormal expression (gain or loss) are associated with the development, growth, or progression of NEOPLASMS. Some neoplasm proteins are tumor antigens (ANTIGENS, NEOPLASM), i.e. they induce an immune reaction to their tumor. Many neoplasm proteins have been characterized and are used as tumor markers (BIOMARKERS, TUMOR) when they are detectable in cells and body fluids as monitors for the presence or growth of tumors. Abnormal expression of ONCOGENE PROTEINS is involved in neoplastic transformation, whereas the loss of expression of TUMOR SUPPRESSOR PROTEINS is involved with the loss of growth control and progression of the neoplasm.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.M Phase Cell Cycle Checkpoints: The cellular signaling system that halts the progression of cells through MITOSIS or MEIOSIS if a defect that will affect CHROMOSOME SEGREGATION is detected.Electrophoresis, Polyacrylamide Gel: Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.
2004). "Cyclin-dependent kinases phosphorylate human Cdt1 and induce its degradation". J. Biol. Chem. 279 (17): 17283-8. doi: ... 2004). "Cdt1 phosphorylation by cyclin A-dependent kinases negatively regulates its function without affecting geminin binding ...
Deshaies, R.J., Chau, V., and Kirschner, M.W. (1995). Ubiquitination of the G1 cyclin Cln2p by a Cdc34p-dependent pathway. EMBO ... and Cdc53/Cullin Catalyzes Ubiquitination of the Phosphorylated CDK Inhibitor Sic1. Cell 91, 221-230 ... Verma, R., Annan, R., Huddleston, M., Carr, S., Reynard, G., and Deshaies, R.J. (1997). Phosphorylation of Sic1p by G1 cyclin/ ... they established that an early step in the release of Cdc14 from Net1 is the phosphorylation of Net1 by the mitotic cyclin-Cdk ...
"Distinct roles for cyclin-dependent kinases in cell cycle control." Science 262.5142 (1993): 2050-2054. Harlow, E. D., et al. " ... "The retinoblastoma protein is phosphorylated during specific phases of the cell cycle." Cell 58.6 (1989): 1097-1105. van den ... "p35 is a neural-specific regulatory subunit of cyclin-dependent kinase 5." (1994): 419-423. Meyerson, Matthew, et al. "A family ... Tsai, L (1994). "p35 is a neural-specific regulatory subunit of cyclin-dependent kinase 5". Nature. 371: 419-23. doi:10.1038/ ...
... on CDK1 must be phosphorylated by a Cyclin Activating Kinase (CAK). CAK only phosphorylates Thr-161 when cyclin B is attached ... The mitotic cyclins can be grouped as cyclins A & B. These cyclins have a nine residue sequence in the N-terminal region called ... Cyclin-dependent kinase 1 (CDK1), the cyclin-dependent kinase subunit. It uses ATP to phosphorylate specific serine and ... During the transition of G2 to M phase, cdk1 is de-phosphorylated by CDC25. The CDK1 subunit is now free and can bind to cyclin ...
Sic1 releases SPF from inhibition after it is phosphorylated by G1-cyclin-CDK. The phosphorylation marking SPF for ... The S-phase-promoting factor (SPF) is a CDK-cyclin complex that induces the S-phase (synthesis phase) of the cell cycle. The S- ... Toward the end of the G1 phase of mitosis, an SPF is phosphorylated, causing a biochemical cascade that results in the ... a protein which also is a stoichiometric inhibitor of Cdk1-Clb and B-type cyclins). ...
Cyclin T1/Cdk9 phosphorylates a region of RNA polymerase II. Such phosphorylation of the polymerase enhances its ability to ... Several cell cycle regulatory functions may be mediated by Pur-alpha binding to Cyclin/Cdk protein kinases, which phosphorylate ... Pur-alpha also binds Cyclin T1, a regulatory partner of Cdk9 protein kinase, necessary for Tat activity. ... "Functional interaction of Puralpha with the Cdk2 moiety of cyclin A/Cdk2". Biochemical and Biophysical Research Communications ...
Akt phosphorylates Caspase-9 on Ser196, preventing a caspase cascade leading to cell death. Akt also phosphorylates MAP kinase ... Akt promotes cyclin D1 translation via indirect activation of mTOR. mTOR increases translation of cyclin D1 by activating ... Akt phosphorylates p27kip1 at Thr157, preventing its nuclear import. In addition, Akt phosphorylates Thr145 and Ser146 of ... phosphorylated at Ser648, promoting cytoskeletal rearrangements and migration Filamin A - phosphorylated at Ser2152, promoting ...
The specific complexes that phosphorylate Rb are cyclin D-cdk4 and cyclin E-cdk2. When Rb has been phosphorylated many times, ... Expression of cyclin D, ckd4, cyclin E and cdk2 decreases when TIGAR is active, due to a lack of ATP essential for their ... Rb will become phosphorylated in a specific set of sequential steps by proteins called cyclin dependent kinases (cdks) bound to ... At the very start of G1 phase, a protein called retinoblastoma (Rb) exists in an un-phosphorylated state. In this state, Rb ...
Cyclin-dependent kinase 5 (Cdk5), a major regulator of neuronal migration and positioning, is known to phosphorylate DAB1 and ... Keshvara L, Magdaleno S, Benhayon D, Curran T (Jun 2002). "Cyclin-dependent kinase 5 phosphorylates disabled 1 independently of ... It becomes phosphorylated by Src and Fyn kinases and apparently stimulates the actin cytoskeleton to change its shape, ... Beffert U, Weeber EJ, Morfini G, Ko J, Brady ST, Tsai LH, Sweatt JD, Herz J (Feb 2004). "Reelin and cyclin-dependent kinase 5- ...
Ruffner, H; Jiang W, Craig A G, Hunter T, Verma I M (1999). «BRCA1 is phosphorylated at serine 1497 in vivo at a cyclin- ... cyclins and cyclin dependent kinases». Oncogene. 15 (2): 143-57. PMID 9244350. doi:10.1038/sj.onc.1201252. !CS1 manut: Nomes ... cyclins and cyclin dependent kinases». Oncogene. 15 (2): 143-57. PMID 9244350. doi:10.1038/sj.onc.1201252. A referência emprega ... O'Brien, K A; Lemke S J, Cocke K S, Rao R N, Beckmann R P (1999). «Casein kinase 2 binds to and phosphorylates BRCA1». Biochem ...
2002). "WARTS tumor suppressor is phosphorylated by Cdc2/cyclin B at spindle poles during mitosis". FEBS Lett. 529 (2-3): 319- ... The protein is phosphorylated in a cell-cycle dependent manner, with late prophase phosphorylation remaining through metaphase ... indicating a role as a negative regulator of CDC2/cyclin A. In addition, the C-terminal kinase domain binds to its own N- ... localized to mitotic apparatus and specifically phosphorylated during mitosis". FEBS Lett. 459 (2): 159-65. doi:10.1016/S0014- ...
Ko LJ, Shieh SY, Chen X, Jayaraman L, Tamai K, Taya Y, Prives C, Pan ZQ (December 1997). "p53 is phosphorylated by CDK7-cyclin ... Ababneh M, Götz C, Montenarh M (May 2001). "Downregulation of the cdc2/cyclin B protein kinase activity by binding of p53 to ... Zhao L, Samuels T, Winckler S, Korgaonkar C, Tompkins V, Horne MC, Quelle DE (January 2003). "Cyclin G1 has growth inhibitory ... The p21 protein binds directly to cyclin-CDK complexes that drive forward the cell cycle and inhibits their kinase activity ...
Ko LJ, Shieh SY, Chen X, Jayaraman L, Tamai K, Taya Y, Prives C, Pan ZQ (1997). "p53 is phosphorylated by CDK7-cyclin H in a ... Cyclin-dependent kinases (CDKs), which play an essential role in cell cycle control of eukaryotic cells, are phosphorylated and ... Ko LJ, Shieh SY, Chen X, Jayaraman L, Tamai K, Taya Y, Prives C, Pan ZQ (December 1997). "p53 is phosphorylated by CDK7-cyclin ... Cyclin H, Cyclin-dependent kinase 7, Estrogen receptor alpha, MCM7, MTA1, P53, and POU2F1. GRCh38: Ensembl release 89: ...
In S. pombe, Wee1 is phosphorylated Cdk1 and cyclin B make up the maturation promoting factor (MPF) which promotes the entry ... Wee1 inhibits Cdk1 by phosphorylating it on two different sites, Tyr15 and Thr14. Cdk1 is crucial for the cyclin-dependent ... cyclin-dependent kinase Cdc28 (Cdk1 homologue) is phosphorylated by Swe1 (Wee1 homologue) and dephosphorylated by Mih1 (Cdc25 ... Swe1 is also phosphorylated by Clb2-Cdc28 which serves as a recognition for further phosphorylation by Cdc5. The S. cerevisiae ...
Cyclin D - Cdk 4/6 Mono-phosphorylates RbEdit. When a cell enters G1, Cyclin D- Cdk4/6 phosphorylates Rb at a single ... Deregulation of Cyclin D - Cdk 4/6 phosphorylates un-phosphorylated Rb in senescent cells to mono-phosphorylated Rb, causing ... When it is time for a cell to enter S phase, complexes of cyclin-dependent kinases (CDK) and cyclins phosphorylate Rb to pRb, ... After a cell passes the restriction point, Cyclin E - Cdk 2 hyper-phosphorylates all mono-phosphorylated isoforms. While the ...
de 2001). «Cyclin A1 directly interacts with B-myb and cyclin A1/cdk2 phosphorylate B-myb at functionally important serine and ... de 1999). «BRCA1 is phosphorylated at serine 1497 in vivo at a cyclin-dependent kinase 2 phosphorylation site». Mol. Cell. Biol ... de 2002). «Reversal of growth suppression by p107 via direct phosphorylation by cyclin D1/cyclin-dependent kinase 4». Mol. Cell ... de 1997). «Identification of a p130 domain mediating interactions with cyclin A/cdk 2 and cyclin E/cdk 2 complexes». Oncogene ( ...
This virus expresses a viral cyclin which builds a complex with Cdk6. This KSHV-cyclin-Cdk6 complex phosphorylates and ... but p27Kip1 inhibits G1 cyclins and not cyclin B. There are several human diseases that are linked to p27Kip1 and other cyclin ... In order to be recognized by Cdc4 of the SCF complex, Sic1 has to be phosphorylated, often by Cyclin-Cdk complexes, at least at ... S-phase cyclins use RXL docking while G1 cyclins use LLPP docking. Sic1 phosphorylation increases when the RXL motif of Clb5 is ...
... cyclin box.' In mammalian cells, 9 cyclin species have been identified, and they are referred to as cyclins A through I. Cyclin ... The N-terminal kinase domain is able to phosphorylate histone H1. The subdomain tension-like N terminal function has not yet ... Cyclin G-associated kinase received its name because it immunoprecipitated with cyclin G though it now appears to not be ... Cyclin G-associated kinase (GAK) is a serine/threonine kinase that in humans is encoded by the GAK gene. In all eukaryotes, the ...
Floyd SR, Porro EB, Slepnev VI, Ochoa GC, Tsai LH, De Camilli P (March 2001). "Amphiphysin 1 binds the cyclin-dependent kinase ... 5 regulatory subunit p35 and is phosphorylated by cdk5 and cdc2". The Journal of Biological Chemistry. 276 (11): 8104-10. doi: ... Floyd SR, Porro EB, Slepnev VI, Ochoa GC, Tsai LH, De Camilli P (March 2001). "Amphiphysin 1 binds the cyclin-dependent kinase ... cdk) 5 regulatory subunit p35 and is phosphorylated by cdk5 and cdc2". The Journal of Biological Chemistry. 276 (11): 8104-10. ...
... transcription elongation factor B phosphorylates hSPT5 and RNA polymerase II carboxyl-terminal domain independently of cyclin- ... of cellular CDK9 and cyclin T1, and hence increases the production of full-length viral RNA. ...
Cyclin D-CDK4 complexes are major integrators of various mitogenic and antimitogenic signals. Also phosphorylates SMAD3 in a ... cyclin-dependent protein serine/threonine kinase regulator activity. • protein binding. • ATP binding. • cyclin binding. • ... Component of the ternary complex, cyclin D/CDK4/CDKN1B, required for nuclear translocation and activity of the cyclin D-CDK4 ... 1993). "Direct binding of cyclin D to the retinoblastoma gene product (pRb) and pRb phosphorylation by the cyclin D-dependent ...
NPAT activates histone gene expression only after it has been phosphorylated by the G1/S-Cdk cyclin E-Cdk2 in early S phase.[ ... The same enzyme that phosphorylates the CTD also phosphorylates the Rad6 complex, which in turn adds a ubiquitin mark ... SLBP are marked for degradation by phosphorylation at two threonine residues by cyclin dependent kinases, possibly cyclin A/ ... Phosphorylated H2AX (also known as gamma H2AX) is a marker for DNA double strand breaks, and forms part of the response to ...
M-Cdks phosphorylate subunits on the APC/C that promote binding to Cdc20. Securin and M cyclins (cyclin A and cyclin B) are ... However, G1/S cyclins are not substrates of APC/CCdh1 and therefore accumulate throughout this phase and phosphorylate Cdh1. By ... In this manner, cyclin A can be degraded while cyclin B and securin are degraded only once sister chromatids have achieved bi- ... Cyclin A is degraded early in mitosis, supporting the theory, but cyclin B and securin are not degraded until metaphase. The ...
It phosphorylates other proteins, and is itself also phosphorylated when interacting with cyclin-dependent kinase 5 (cdk5)/p35 ... LMTK2 has been shown to interact with PPP1CA, Cyclin-dependent kinase 5 and PPP1R2. GRCh38: Ensembl release 89: ENSG00000164715 ... cyclin-dependent kinase 5/p35-regulated kinase". The Journal of Neuroscience. 23 (12): 4975-83. PMID 12832520. Eeles RA, Kote- ... cyclin-dependent kinase 5/p35-regulated kinase". The Journal of Neuroscience. 23 (12): 4975-83. PMID 12832520. Wang H, ...
2001). "Amphiphysin 1 binds the cyclin-dependent kinase (cdk) 5 regulatory subunit p35 and is phosphorylated by cdk5 and cdc2 ... Cyclin-dependent kinase 5 activator 1 is an enzyme that in humans is encoded by the CDK5R1 gene. The protein encoded by this ... "Entrez Gene: CDK5R1 cyclin-dependent kinase 5, regulatory subunit 1 (p35)". Hoek KS, Schlegel NC, Eichhoff OM, et al. (2008). " ... Floyd SR, Porro EB, Slepnev VI, Ochoa GC, Tsai LH, De Camilli P (March 2001). "Amphiphysin 1 binds the cyclin-dependent kinase ...
cyclin-dependent protein kinase 5 activator activity. • lipid binding. Cellular component. • cytoplasm. • cyclin-dependent ... is associated with protein phosphatase 1 and phosphorylates inhibitor-2". J. Biol. Chem. 276 (26): 23712-8. doi:10.1074/jbc. ... CDK5R2, NCK5AI, P39, p39nck5ai, cyclin-dependent kinase 5, regulatory subunit 2 (p39), cyclin dependent kinase 5 regulatory ... Cyclin-dependent kinase 5 activator 2 is an enzyme that in humans is encoded by the CDK5R2 gene. ...
Frequent loss of PTEN expression is linked to elevated phosphorylated Akt levels, but not associated with p27 and cyclin D1 ... Frequent Loss of PTEN Expression Is Linked to Elevated Phosphorylated Akt Levels, but Not Associated with p27 and Cyclin D1 ... Frequent Loss of PTEN Expression Is Linked to Elevated Phosphorylated Akt Levels, but Not Associated with p27 and Cyclin D1 ... Frequent Loss of PTEN Expression Is Linked to Elevated Phosphorylated Akt Levels, but Not Associated with p27 and Cyclin D1 ...
Thr 160 phosphorylated CDK2 - Human cyclin A3 complex with the inhibitor indirubin-5-sulphonate bound. *DOI: 10.2210/pdb1E9H/ ... CYCLIN A3. B, D. 261. Homo sapiens. Mutation(s): 0 Gene Names: CCNA2, CCN1, CCNA. ... Cyclin-dependent kinase 2 (CDK2) is an important target for structure-based design of antitumor agents. Monomeric CDK2 is ... Cyclin-dependent kinase 2 (CDK2) is an important target for structure-based design of antitumor agents. Monomeric CDK2 is ...
CCND1 (cyclin D1), a key regulator of the mammalian G1-S-phase transition, is phosphorylated on Thr286 by GSK3β (glycogen ... A novel DYRK1B inhibitor AZ191 demonstrates that DYRK1B acts independently of GSK3β to phosphorylate cyclin D1 at Thr286, not ... A novel DYRK1B inhibitor AZ191 demonstrates that DYRK1B acts independently of GSK3β to phosphorylate cyclin D1 at Thr286, not ... AZ191, cell cycle, cyclin D1, dual-specificity tyrosine phosphorylation-regulated kinase 1B (DYRK1B), glycogen synthase kinase ...
Strikingly, cyclin A1, but not cyclin A2 or cyclin B1, was evidently up-regulated ( Fig. 4A ). Notably, cyclin D1 was slightly ... cyclin A1 and A2. Whereas cyclin A1 is limited to male germ cells, cyclin A2 is widely expressed. Cyclin A2 regulates both G1-S ... cyclin A1, and cyclin A2 antibodies, respectively. Depletion of SRPK2 prominently decreased cyclin A1 but not cyclin A2 ... Cyclin A1 but not cyclin A2 or cyclin B1 was selectively increased in SRPK2 wild-type cells, and the stimulatory effect was ...
This was followed by a rapid fall in cyclin A and B and a coordinate dephosphorylation of the retinoblastoma protein (pRb). The ... cycle arrest and differentiation showed that the onset of cell cycle arrest was associated with a decrease in c-Myc and cyclin ... arrest by constitutive expression of Stat1Y701F or Stat1S727A was associated with impaired regulation of these cyclins and p27 ...
You can think of the cyclin as the gas for the cell cycle car. Even though the car has an engine (cdk), and gas (cyclin), it is ... If there is DNA damage, the cell can stick in G2.) The cdks are also important in mitosis (M). They phosphorylate many proteins ... The cyclin dependent kinases, or cdks, are the proteins that drive the cell cycle. You can think of them as the engines that ... In order to be active (able to stick phosphate groups on other proteins) they have to have a partner, called a cyclin. ...
... and some of these were shown to complex with different cyclins and to be active at discrete stages of the cell cycl … ... Mammalian cell cycle progression is regulated by sequential activation and inactivation of cyclin-dependent kinases (cdks). ... In the current work, we found that PITALRE kinase activity phosphorylated pRb at sites similar to those phosphorylated by the ... CDC2-related Kinase PITALRE Phosphorylates pRb Exclusively on Serine and Is Widely Expressed in Human Tissues J Cell Physiol. ...
Interestingly, Mer2 was not phosphorylated at early times or in the absence of Clb5/Clb6 even though other B-type cyclin-CDK ... CDK-cyclin complexes phosphorylate Mer2 directly. These findings demonstrate that phosphorylation of Mer2 requires CDK activity ... we conclude that Mer2 can be directly phosphorylated by CDK-cyclin complexes. ... Cyclin-dependent kinase directly regulates initiation of meiotic recombination. Kiersten A. Henderson,1,2 Kehkooi Kee,1,2,3 ...
Potent inhibitor of cyclin E- and cyclin A-CDK2 complexes. Forms a complex with cyclin type D-CDK4 complexes and is involved in ... Inhibits the kinase activity of CDK2 bound to cyclin A, but has little inhibitory activity on CDK2 bound to SPDYA. Involved in ... Acts either as an inhibitor or an activator of cyclin type D-CDK4 complexes depending on its phosphorylation state and/or ... Interacts (phosphorylated on Tyr-88 and Tyr-89) with CDK4; the interaction is required for cyclin D and CDK4 complex assembly, ...
May act at least in part via inhibition of the cyclin-D1/CDK4 complex, thereby preventing phosphorylation of RB1 and blocking ... Phosphorylated.1 Publication. Manual assertion based on experiment ini. *. Ref.1 ... Cyclin-D1-binding protein 1Add BLAST. 359. Amino acid modifications. Feature key. Position(s). DescriptionActions. Graphical ... "GCIP, a novel human grap2 and cyclin D interacting protein, regulates E2F-mediated transcriptional activity.". Xia C., Bao Z., ...
These kinases phosphorylate and inactivate the retinoblastoma protein (Rb). Rb phosphorylation is completed by Cdk2 kinase in ... D) Gene expression analysis of cyclin E1 (Left), cyclin E2 (Middle), and cyclin A2 (Right) in livers of DEN-treated Cdk2f/f (n ... E-type cyclins E1 (CcnE1) and E2 (CcnE2) are regulatory subunits of cyclin-dependent kinase 2 (Cdk2) and thought to control the ... For the isolation of cyclin E1 or Cdk2 floxed primary hepatoma cells, we used mice with a floxed allele of cyclin E1 (CcnE1f/f ...
Here, we identify that cyclin B1/CDK1-phosphorylates iASPP, which leads to the inhibition of iASPP dimerization, promotion of ... Most wild-type p53-expressing melanoma cell lines coexpress high levels of phosphorylated nuclear iASPP, MDM2, and cyclin B1. ... Restoring p53 function in human melanoma cells by inhibiting MDM2 and cyclin B1/CDK1-phosphorylated nuclear iASPP. ... Here, we identify that cyclin B1/CDK1-phosphorylates iASPP, which leads to the inhibition of iASPP dimerization, promotion of ...
Interacts with a yet unknown type of cyclin. Can phosphorylate histone H1. ...
AKT also phosphorylates and inhibits glycogen synthase kinase 3 (GSK3). GSK3 phosphorylates cyclin D, targeting it for ... PDK1 also phosphorylates and enables activation of p70S6kinase and protein kinase C (PKC) family members. PTEN turns off the ... B) The class I PI3K enzymes can phosphorylate the 3 position of PtdIns, PtdIns-4-P, or PtdIns-4,5-P2 to produce PtdIns-3-P, ... In addition, PtdIns-3,4-P2 can be produced by phosphorylating the 4 position of PtdIns-3-P [reviewed by Fruman et al. (76)]. ...
... phosphorylated CaMKII; CDK5, cyclin-dependent kinase 5; GluR1, ionotropic glutamate receptor subunit 1; SCX, strong cation ... In total, we identified 998 unique phosphorylated peptides, mapping to 723 unique sites of phosphorylation. At least one exact ...
Furthermore, MTA1 overexpression inhibited the ability of CAK complex to phosphorylate ER. Together, these findings identified ... MAT1 is an assembly/targeting factor for cyclin-dependent kinase-activating kinase (CAK), which has been shown to functionally ... MTA1 interacts with MAT1, a cyclin-dependent kinase-activating kinase complex ring finger factor, and regulates estrogen ...
CDK8 binds to and/or phosphorylates several transcription factors, which can have an activating or inhibitory effect on ... Rickert P, Corden JL, Lees E (Jan 1999). "Cyclin C/CDK8 and cyclin H/CDK7/p36 are biochemically distinct CTD kinases". Oncogene ... The protein encoded by this gene is a member of the cyclin-dependent protein kinase (CDK) family. CDK8 and cyclin C associate ... "Entrez Gene: CDK8 cyclin-dependent kinase 8".. *^ Nemet J, Jelicic B, Rubelj I, Sopta M (Feb 2014). "The two faces of Cdk8, a ...
... by the cyclin-dependent kinase (CDK) 9. Using CDK9 inhibitors and global run-on sequencing (GRO-seq), we have mapped CDK9 ... Cyclin-Dependent Kinase 9 / metabolism * Glyceraldehyde-3-Phosphate Dehydrogenase (Phosphorylating) / biosynthesis* * HEK293 ... by the cyclin-dependent kinase (CDK) 9. Using CDK9 inhibitors and global run-on sequencing (GRO-seq), we have mapped CDK9 ...
Since mESCs lack cyclin D-CDK4 as well as cyclin E-CDK2, pRb will not be phosphorylated and thereby not stimulating the cyclin ... some studies revealed the miR-15a/16 family as regulator of various cyclins, including cyclins D1 and D2 and cyclin E1, and pRb ... The latter include cyclin D, cyclin A, CDK1, CDK2, CDK4, CDK6, CDK8 and CDC25A [115, 177, 180]. Also, it has been shown that ... Cyclin D proteins bind to enzymes called CDK4/6 and together they form heterodimers. These complexes subsequently phosphorylate ...
... cyclin D3 (Neo Markers); cyclin E (Santa Cruz Biotechnology); unphosphorylated RB (PharMingen); phosphorylated RB (PharMingen ... cyclin A and cyclin E, respectively. CDK4-cyclin D, CDK6-cyclin D, and cyclin D1-CDK4/6 kinase activities were also examined by ... CDK2-cyclin A and CDK2-cyclin E kinase activities, obtained from immunocomplexes of cyclin A or cyclin E, were also measured, ... 2) ⇓ . There was no obvious difference in the expression levels of CDK2, CDK4, CDK6, cyclin D1, cyclin D3, cyclin E, and p21 ...
1995) Induction of cyclin B and H1 kinase activity in apoptotic PC12 cells. Exp Cell Res 219:612-618, pmid:7641812.. ... that is weakly phosphorylated in untreated cell lysates and strongly phosphorylated in lysates from apoptotic cells. Similarly ... 1994) Activation of cyclin A-dependent protein kinases during apoptosis. Proc Natl Acad Sci USA 91:3754-3758, pmid:8170983.. ... 1995) Fas-activated serine/threonine kinase (FAST) phosphorylates TIA-1 during Fas-mediated apoptosis. J Exp Med 182:865-874, ...
Potent inhibitor of cyclin E- and cyclin A-CDK2 complexes. Forms a complex with cyclin type D-CDK4 complexes and is involved in ... The phosphorylated form found in the cytoplasm is inactivate. Phosphorylation on Thr-198 is required for interaction with 14-3- ... PTM: Phosphorylated; phosphorylation occurs on serine, threonine and tyrosine residues. Phosphorylation on Ser-10 is the major ... Acts either as an inhibitor or an activator of cyclin type D-CDK4 complexes depending on its phosphorylation state and/or ...
... cyclin-dependent kinase 5 (cdk5) was shown to phosphorylate specifically the KSPXK repeats in rat NF-H. Because 80% of the ... Erk1 and Erk2 phosphorylate all KSP motifs. We next tested whether Erk1 and Erk2 were capable of phosphorylating other KSP ... Erk2 phosphorylates bacterially expressed rat NF-H and a NF-H KSP repeat tail domain. Because Erk2 phosphorylated small (14mer- ... with MEK phosphorylating Erk2, which, in turn, was activated to phosphorylate the peptide. This hypothesis also offered an ...
Cyclin D - Cdk 4/6 Mono-phosphorylates RbEdit. When a cell enters G1, Cyclin D- Cdk4/6 phosphorylates Rb at a single ... Deregulation of Cyclin D - Cdk 4/6 phosphorylates un-phosphorylated Rb in senescent cells to mono-phosphorylated Rb, causing ... When it is time for a cell to enter S phase, complexes of cyclin-dependent kinases (CDK) and cyclins phosphorylate Rb to pRb, ... After a cell passes the restriction point, Cyclin E - Cdk 2 hyper-phosphorylates all mono-phosphorylated isoforms. While the ...
2004). "Cyclin-dependent kinases phosphorylate human Cdt1 and induce its degradation". J. Biol. Chem. 279 (17): 17283-8. doi: ... 2004). "Cdt1 phosphorylation by cyclin A-dependent kinases negatively regulates its function without affecting geminin binding ...
- The cdks are also important in mitosis (M). They phosphorylate many proteins that are necessary for cells to separate their chromosomes and divide. (madsci.org)
- This transition requires phosphorylation and activation of CDKs by cyclins. (aacrjournals.org)
- CDKs activity is closely associated with specific cyclin co-factors and at least 12 separate genetic loci are known to code for the CDKs. (omicsonline.org)
- CDKs absolutely require binding of an ancillary subunit, the cyclin, for their activity ( 30 ). (asm.org)
- CDKs are called "cyclin-dependent" because their activity requires their association with activating subunits called cyclins. (encyclopedia.com)
- While the number of CDKs in a cell remains constant during the cell cycle, the levels of cyclins oscillate. (encyclopedia.com)
- They found that G 1 -Cdks directly phosphorylate Sic1p, an inhibitor of S phase-Cdks. (sciencemag.org)
- These cyclins oscillate, increasing and decreasing at different stages, binding to CDKs and driving the cell cycle forward. (news-medical.net)
- In addition to cyclin levels, this provides and additional way to control the activity of CDKs. (news-medical.net)
- Cdh1 is prevented from interaction with APC/C when Cdh1 is phosphorylated by Cdks. (rupress.org)
- A cyclin-dependent kinase (cdk)-activating kinase (CAK) has been shown previously to catalyze T-loop phosphorylation of cdks in most eukaryotic cells. (semanticscholar.org)
- Cdk7 is unusual among cdks because it contains not one but two residues (S170 and T176 in Xenopus cdk7) in its T-loop that are phosphorylated in vivo. (semanticscholar.org)
- By phosphorylating (linking a phosphate) to proteins in the cell, Cdks work to turn on and off other proteins that play roles in the cell cycle. (apologeticspress.org)
- But, Cdks themselves need an "on switch," which comes from the cyclin proteins. (apologeticspress.org)
- Acts either as an inhibitor or an activator of cyclin type D-CDK4 complexes depending on its phosphorylation state and/or stoichometry. (uniprot.org)
- Perhaps the best-characterized pathway includes D-type cyclin/cdk complexes, which can be oncogenes, and two tumor suppressor genes, the p16 cyclin/cdk inhibitor and the retinoblastoma gene product (reviewed in ref. 1 ). (pnas.org)
- We found that levels of the cyclin-dependent kinase (CDK) inhibitor, p27, were lower in U87MG.ΔEGFR tumors than in parental U87MG or control U87MG.DK tumors. (aacrjournals.org)
- Treatment of U87MG.ΔEGFR cells with LY294002, a PI3-K inhibitor, caused reduced levels of phosphorylated Akt and concomitantly up-regulated levels of p27. (aacrjournals.org)
- The activity of this kinase is restricted to the G1-S phase, which is controlled by the regulatory subunits D-type cyclins and CDK inhibitor p16 INK4a . (wikipedia.org)
- The protein synthesis inhibitor silvestrol has potent activity in B-cell leukemias via the mitochondrial pathway of apoptosis, and also reduces cyclin D1 expression in breast cancer and lymphoma cell lines. (aacrjournals.org)
- The antiproliferative effects of the AIs were examined in aromatase-overexpressing MCF-7/Ac1 cells in the presence or absence of full-length cyclin E and LMW-E. Inhibition of LMW cyclin E kinase activity by roscovitine [a cyclin-dependent kinase (CDK) inhibitor] was examined in letrozole-unresponsive MCF-7/Ac1 cells. (aacrjournals.org)
- Inhibition of cyclin E/cyclin-dependent kinase 2 activity through increased binding of the cell cycle inhibitor p27 to the complex is a key mediator of the antiproliferative effects of letrozole. (aacrjournals.org)
- Lastly, we show that breast cancer patients whose tumors overexpress LMW cyclin E are more likely to recur after AI treatment compared with those with low or no expression of LMW cyclin E. These data support clinical investigation of cyclin-dependent kinase 2 inhibitor therapy for postmenopausal women with estrogen receptor-positive, LMW cyclin E-expressing breast cancer. (aacrjournals.org)
- Cyclin-dependent kinase 6 (CDK6) bound to the inhibitor ribociclib (detail view). (news-medical.net)
- Here we report that inhibition of cyclin-dependent kinase 4 (Cdk4) by fascaplysin (a small molecule selective inhibitor of Cdk4/cyclin D1 that we identified in a screen for compounds that inhibit PAX3-FOXO1) led to inhibition of the transcriptional activity of PAX3-FOXO1 in ARMS cell line Rh30. (jove.com)
- CDKN2A, cyclin dependent kinase inhibitor 2A (cyclin dependent kinase inhibitor 2A regulates cell cycle G1 progression by inhibiting CDK4 kinase. (thefreedictionary.com)
- Forms a complex with cyclin type D-CDK4 complexes and is involved in the assembly, stability, and modulation of CCND1-CDK4 complex activation. (uniprot.org)
- May act at least in part via inhibition of the cyclin-D1/CDK4 complex, thereby preventing phosphorylation of RB1 and blocking E2F-dependent transcription. (uniprot.org)
- Glioblastomas have been shown to express increased levels of cyclin D (11 , 12) , contain amplification of CDK4/6 genes (13 , 14) , or have reduced levels of the CDKI, p27 (15 , 16 , 17) , suggesting that CDK-cyclin kinase activities are elevated in glioblastomas. (aacrjournals.org)
- Cyclin-dependent kinase 4 also known as cell division protein kinase 4 is an enzyme that in humans is encoded by the CDK4 gene . (wikipedia.org)
- CDK4 is a member of the cyclin-dependent kinase family. (wikipedia.org)
- Ser/Thr-kinase component of cyclin D-CDK4 (DC) complexes that phosphorylate and inhibit members of the retinoblastoma (RB) protein family including RB1 and regulate the cell-cycle during G1/S transition. (wikipedia.org)
- Cyclin D-CDK4 complexes are major integrators of various mitogenic and antimitogenic signals. (wikipedia.org)
- Component of the ternary complex, cyclin D/CDK4/CDKN1B, required for nuclear translocation and activity of the cyclin D-CDK4 complex. (wikipedia.org)
- Genetic alterations usually affect CDK4 and CDK6, their positive (mainly cyclin D1) and negative (INK4A and INK4B) regulators and their substrates (mainly RB). (nature.com)
- Mitotic stimulation can induce entry into the cell cycle in the G 1 phase by assembly of d -type cyclin with Cdk4/6 ( 10 , 11 ). (diabetesjournals.org)
- Cyclin D2 and CDK4 have been shown to be essential for the replication of β-cells ( 9 , 14 ). (diabetesjournals.org)
- The activated cyclin d -Cdk4/6 complexes phosphorylate retinoblastoma (pRb) (rev. in 12 , 13 ). (diabetesjournals.org)
- Thus, while cyclin D2-Cdk4 complex formation is clearly essential for β-cell proliferation, it alone is unlikely to be sufficient for committing a cell to divide. (diabetesjournals.org)
- These include the Ink4 family, members of which specifically inhibit cyclin d -Cdk4/6 activity, and the CIP/KIP family, which includes p21, p27, and p57, which exhibit promiscuous CDK-inhibitory activity. (diabetesjournals.org)
- Initially, a mitogenic stimulus leads to the upregulation of cyclin D gene expression, which binds to CDK4. (news-medical.net)
- Retinoblastoma protein (Rb) usually functions to inhibit the transcription factor E2F, however, when cyclin-D-CDK4 phosphorylates the Rb protein, this relinquishes inhibition of E2F and leads to the production of genes required for entering the S phase. (news-medical.net)
- These genes include cyclin E, which binds to CDK4, driving the cell cycle into the S phase. (news-medical.net)
- In vitro kinase assays revealed that Cdk4 directly phosphorylated PAX3-FOXO1 at Ser(430). (jove.com)
- Our findings indicate that Cdk4 phosphorylates and positively regulates PAX3-FOXO1 and suggest that inhibition of Cdk4 activity should be explored as a promising avenue for developing therapy for ARMS. (jove.com)
- CDK6, with CDK4, phosphorylates and regulates the activity of tumour suppressor protein Rb. (thefreedictionary.com)
- Further studies led to the observation that ICP0 and cyclin D3 colocalize in the infected cell nuclei and that ICP0 does not interfere with the phosphorylation of retinoblastoma protein (pRb) by cyclin D3-cdk4 complex. (asm.org)
- This was followed by a rapid fall in cyclin A and B and a coordinate dephosphorylation of the retinoblastoma protein (pRb). (diva-portal.org)
- Regulation of retinoblastoma protein functions by ectopic expression of human cyclins. (wikipedia.org)
- The Cdk:cyclin complexes of the G1/S transition regulate the progression of cells into the S phase by phosphorylating the retinoblastoma protein (Rb). (diva-portal.org)
- When the cell is ready to divide, Rb is phosphorylated to pRb, leading to the inactivation of the activity of Retinoblastoma protein. (wikipedia.org)
- Cdk-6 and cyclin D 1 in vitro led to marked activation of retinoblastoma protein phosphorylation and cell cycle progression with no induction of cell death. (diabetesjournals.org)
- Cyclin-dependent kinase-like 2 (Cdkl2) is a cdc2-related serine/threonine protein kinase that is postnatally expressed in various brain regions, including the cerebral cortex, entorhinal cortex, hippocampus, amygdala, and dorsal thalamus. (frontiersin.org)
- Sera derived from individual patients precipitated different combinations of seven distinct serine-phosphorylated proteins. (rupress.org)
- Serum from four patients precipitated a serine/threonine kinase from apoptotic cell lysates that phosphorylates proteins of 23-, 34-, and 46-kD in in vitro kinase assays. (rupress.org)
- Once bound to a cyclin they act to phosphorylate many target proteins on serine or threonine amino acid residues. (news-medical.net)
- We further demonstrated that CDK1 phosphorylates C/EBPα on serine 21, which inhibits its differentiation-inducing function. (jci.org)
- Purified cyclin- p34cdc2 phosphorylated the regulatory light chain of cytoplasmic and smooth muscle myosin-II in vitro on serine-1 or serine-2 and threonine-9, sites known to inhibit the actin-activated myosin ATPase activity of smooth muscle and nonmuscle myosin (Nishikawa, M., J. R. Sellers, R. S. Adelstein, and H. Hidaka. (xenbase.org)
- Serine-1 or -2 of the regulatory light chain of Xenopus cytoplasmic myosin-II was also phosphorylated in Xenopus egg lysates stabilized in metaphase, but not in interphase. (xenbase.org)
- Conti, Identification of the serine residue phosphorylated by protein kinase C in vertebrate nonmuscle myosin heavy chains. (xenbase.org)
- CCND1 (cyclin D1), a key regulator of the mammalian G 1 -S-phase transition, is phosphorylated on Thr 286 by GSK3β (glycogen synthase kinase 3β) to promote its degradation. (portlandpress.com)
- and for cyclin B degradation. (ebi.ac.uk)
- Gcn4 degradation depends on the ubiquitination complex SCF CDC4 and requires phosphorylation by the cyclin-dependent kinase Pho85. (asm.org)
- Here, we show that Pcl5 is the Pho85 cyclin specifically required for Gcn4 degradation. (asm.org)
- In vitro, Pho85, in conjunction with the cyclin Pcl1, is able to phosphorylate Gcn4 at the critical residue for degradation, Thr165 ( 26 ). (asm.org)
- Acts as a negative regulator of p53 family members: phosphorylates TOPORS, leading to inhibit the sumoylation of p53/TP53 and simultaneously enhance the ubiquitination and subsequent degradation of p53/TP53. (nih.gov)
- Phosphorylates BORA, and thereby promotes the degradation of BORA. (nih.gov)
- In the absence of such suppression of centrosomal phosphatase activity, further activation of Cdk1 would not be expected to occur because of the premature degradation of cyclin B, Plk1, and Aurora A. (rupress.org)
- A number of studies have described the ability of over-expressed cyclin A to accelerate the G1 to S transition causing DNA replication, and cyclin A antisense DNA can prevent DNA replication (2-4). (cellsignal.com)
- Cdk-6 overexpression, alone or in combination with cyclin D 1 , strikingly stimulates human β-cell replication, both in vitro as well as in vivo, without inducing cell death or loss of function. (diabetesjournals.org)
- Furthermore, we show that cdk-6 and a d -cyclin partner can be used to markedly accelerate replication in human β-cells in vitro. (diabetesjournals.org)
- Most importantly, we show that combined overexpression of cdk-6 with cyclin D 1 also leads to human β-cell replication in vivo and results in enhanced human islet engraftment and function in an in vivo transplant diabetes model. (diabetesjournals.org)
- The malarial CDK Pfmrk and its effector PfMAT1 phosphorylate DNA replication proteins and co-localize in the nucleus. (semanticscholar.org)
- Cell cycle control of DNA replication in embryonic and somatic cells: cyclins and the cell cycle in Xenopus embryos. (stanford.edu)
- p27 induces G 1 arrest in tumor cells by binding to CDK-cyclin complexes and inhibiting their activities. (aacrjournals.org)
- Cyclin E is a prognostic marker in breast cancer, its altered expression increased with the increasing stage and grade of the tumor. (wikipedia.org)
- The cyclin D/Rb/E2F1 pathway was investigated in vitro using MCL cell lines and primary tumor cells. (aacrjournals.org)
- Cyclin D1 promotes nuclear DNA synthesis through phosphorylation and inactivation of the pRb tumor suppressor. (jefferson.edu)
- MTA1 interacts with MAT1, a cyclin-dependent kinase-activating kinase complex ring finger factor, and regulates estrogen receptor transactivation f. (nih.gov)
- Interacts with CCNC/cyclin-C during interphase. (genecards.org)
- Each interacts with a different cyclin at a different phase, stimulating various target proteins and ensuring that vital stages of each phase are carried out before a cell moves onto the next phase. (news-medical.net)
- Here we demonstrate that the budding yeast cyclin-dependent kinase Cdc28 directly regulates the formation of the DNA double-strand breaks that initiate recombination by phosphorylating the Mer2/Rec107 protein and thereby modulating interactions of Mer2 with other proteins required for break formation. (pubmedcentralcanada.ca)
- Cyclin-dependent kinase 5 regulates PSD-95 ubiquitination in neurons. (springer.com)
- Regulates the dissociation of cohesin from chromosomes by phosphorylating cohesin subunits such as STAG2/SA2. (nih.gov)
- Detailed analysis of the molecular mechanism of ATRA-induced cell cycle arrest and differentiation showed that the onset of cell cycle arrest was associated with a decrease in c-Myc and cyclin E levels and upregulation of p27 Kip1 and p21 WAF1/CIP1 . (diva-portal.org)
- You can think of the cyclin as the gas for the cell cycle car. (madsci.org)
- Most wild-type p53-expressing melanoma cell lines coexpress high levels of phosphorylated nuclear iASPP, MDM2, and cyclin B1. (ox.ac.uk)
- Recently, several new members of the cdk family were cloned, and some of these were shown to complex with different cyclins and to be active at discrete stages of the cell cycle. (nih.gov)
- Cyclin-dependent kinase 5 (CDK5) controls melanoma cell motility, invasiveness, and metastatic spread-identification of a promising novel therapeutic target. (springer.com)
- Also phosphorylates SMAD3 in a cell-cycle-dependent manner and represses its transcriptional activity. (wikipedia.org)
- Oncogenic stimulation recruits cyclin-dependent kinase in the cell cycle start in rat fibroblast. (nature.com)
- cyclin Any of a family of proteins that help control the various phases of the cell cycle . (encyclopedia.com)
- Besides that, dysregulated cyclin E activity causes cell lineage-specific abnormalities, such as impaired maturation due to increased cell proliferation and apoptosis or senescence. (wikipedia.org)
- Cyclin E overexpression can lead to G1 shortening, decrease in cell size or loss of serum requirement for proliferation. (wikipedia.org)
- Impact of cyclin E overexpression on Smad3 activity in breast cancer cell lines. (wikipedia.org)
- Comparison of cyclin A1 and cyclin A promoter activity in adherent and myeloid leukemia cell lines showed that the cyclin A1 promoter is preferentially active in myeloid cell lines. (bloodjournal.org)
- 2 Cyclin A1 is thought to play an important role in the first meiotic cell division in testis and impaired spermatogenesis occurs in mice with cyclin A1 deletion. (bloodjournal.org)
- 3 The relevance of cyclin A1 for the cell cycle in somatic cells is unclear. (bloodjournal.org)
- 15 We show here that the cyclin A1 promoter is preferentially active in myeloid leukemia cell lines and is transactivated by c-myb. (bloodjournal.org)
- Mantle cell lymphoma (MCL), characterized by elevated cyclin D1, was used as a model to test this approach. (aacrjournals.org)
- Cells with damaged DNA recruit γH2AX (phosphorylated histone H2AX), phosphorylate Chk1 (checkpoint kinase 1) and arrest in the G 2 -phase of the cell cycle. (biochemj.org)
- CCND1 expresses the protein cyclin D1, a cell cycle regulator. (news-medical.net)
- Cyclin-dependent kinase 4 is a key regulator of G1 PHASE of the CELL CYCLE. (curehunter.com)
- Once phosphorylated, pRb releases tethered transcription factor E2F and irreversibly commits the cell to progress through the cell cycle (rev. in 14 ). (diabetesjournals.org)
- CDC28 was identified in Saccharomyces cerevisiae , which bound to cyclins and drove the cell through the various transitions of the cell cycle. (news-medical.net)
- In this review we focus on the interaction of viral proteins with important regulators of cell cycle-oncoproteins YB-1, p53, and cyclin D1-which play a major role in cell proliferation, apoptosis, DNA repair, and genomic stability. (hindawi.com)
- The weel kinase phosphorylates only Y-15 residue of cdc2 kinase and T-14 phosphorylation is observed in a intact cell. (nii.ac.jp)
- There is an increase in non-phosphorylated p53, what has been increased in the cell? (sporcle.com)
- In what phase of the cell cycle do M cyclins begin to be produced? (sporcle.com)
- In small G1 cells, the only cyclin known to be present is Cln3, which is expressed relatively constitutively through the cell cycle. (genetics.org)
- The activity of cdc2 was higher in infected cell lysates than those of corresponding proteins present in lysates of mock-infected cells even though cyclins A and B were not detectable in lysates of infected cells. (asm.org)
- Acinus S422D, an SRPK2 phosphorylation mimetic, enhances cyclin A1 transcription, whereas acinus S422A, an unphosphorylatable mutant, blocks the stimulatory effect of SRPK2. (aacrjournals.org)
- Transcription through early-elongation checkpoints requires phosphorylation of negative transcription elongation factors (NTEFs) by the cyclin-dependent kinase (CDK) 9. (nih.gov)
- Gel-shift assays demonstrated that c-myb could bind to the cyclin A1 promoter at a binding site located near the transcription start site. (bloodjournal.org)
- The CTD is unphosphorylated prior to transcription initiation and becomes highly phosphorylated soon thereafter. (genetics.org)
- Clk/Sty was initially cloned as a cyclin-dependent kinase (CDK)-like kinase by PCR ( 4 , 5 ), as well as a dual specificity kinase in an expression screening ( 6 - 8 ). (aacrjournals.org)
- MAT1 is an assembly/targeting factor for cyclin-dependent kinase-activating kinase (CAK), which has been shown to functionally interact with general transcriptional factor TFIIH, a known inducer of ER transactivation. (nih.gov)
- "Identification of human cyclin-dependent kinase 8, a putative protein kinase partner for cyclin C" . Proceedings of the National Academy of Sciences of the United States of America . (wikipedia.org)
- Avraham E, Rott R, Liani E, Szargel R, Engelender S. Phosphorylation of Parkin by the cyclin-dependent kinase 5 at the linker region modulates its ubiquitin-ligase activity and aggregation. (springer.com)
- Cyclin-dependent kinase 5-mediated hyperphosphorylation of sirtuin-1 contributes to the development of endothelial senescence and atherosclerosis. (springer.com)
- Bai B, Vanhoutte PM, Wang Y. Loss-of-SIRT1 function during vascular ageing: hyperphosphorylation mediated by cyclin-dependent kinase 5. (springer.com)
- We found that c-Jun NH 2 -terminal kinase (JNK), not cyclin-dependent kinase 5, is required for APP phosphorylation, leading to localized accumulation of phosphorylated APP (pAPP) in neurites. (jneurosci.org)
- It activates the cyclin-dependent kinase CDC2 by removing two phosphate groups. (genecards.org)
- Herein, cyclin D1 deficiency increased mitochondrial size and activity that was rescued by cyclin D1 in a Cdk-dependent manner. (jefferson.edu)
- Cyclin D1-dependent kinase phosphorylates NRF-1 at S47. (jefferson.edu)
- In agreement with this observation, cdc2 kinase, a cdc2/cyclin B complex essential for G 2 -M phase transition, phosphorylates SF2/ASF ( 11 ). (aacrjournals.org)
- In the current work, we found that PITALRE kinase activity phosphorylated pRb at sites similar to those phosphorylated by the CDC2 kinase, which itself is known to mimic, in vitro, the in vivo phosphorylation of pRb. (nih.gov)
- The weel kinase phosphorylated by cdc2 kinase also bound to 14-3-3 zeta ptotein. (nii.ac.jp)
- Further, cyclin B/cdc2 kinase, weel kinase and 14-3-3 zeta ptotein form a complex. (nii.ac.jp)
- The other kinase which phosphorylates T-14 of cdc2 kinase must exist. (nii.ac.jp)
- This preferential activity was present in a small, 335-bp cyclin A1 promoter fragment that contained several potential c-myb binding sites. (bloodjournal.org)
- Coexpression of a c-myb expression vector with the cyclin A1 promoter constructs significantly increased the reporter activity in adherent CV-1 as well as in myeloid U937 cells. (bloodjournal.org)
- We hypothesized that this dual activity of silvestrol would make it especially effective in malignancies driven by aberrant cyclin D1 expression. (aacrjournals.org)
- Different sites may be phosphorylated at different times, giving rise to many possible conformations and likely many functions/ activity levels. (wikipedia.org)
- Dual phosphorylation of the T-loop in cdk7: its role in controlling cyclin H binding and CAK activity. (semanticscholar.org)
- Many environmental signals regulating Start do so by influencing the synthesis or activity of the G1 cyclins. (genetics.org)
- Therefore, cyclins are considered to be the gears that are changed to aid the transition between cycle phases. (omicsonline.org)
- CDK3/cyclin-C mediated RB1 phosphorylation is required for G0-G1 transition. (genecards.org)
- In uninfected cells the G 2 /M transition is regulated by cyclin kinase complex containing cdc2 and, initially, cyclin A, followed by cyclin B. cdc2 is downregulated through phosphorylation by wee-1 and myt-1 and upregulated by cdc-25C phosphatase. (asm.org)