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 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 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 A2: A widely-expressed cyclin A subtype that functions during the G1/S and G2/M transitions of the CELL CYCLE.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.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.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 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.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.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.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.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.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.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 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.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 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.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.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.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.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.Starfish: Echinoderms having bodies of usually five radially disposed arms coalescing at the center.Phosphorylation: The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.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 2.7.1.37) in which serine residues in protamines and histones are phosphorylated in the presence of ATP.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.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).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.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.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.Cell Division: The fission of a CELL. It includes CYTOKINESIS, when the CYTOPLASM of a cell is divided, and CELL NUCLEUS DIVISION.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.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.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.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.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.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.Xenopus: An aquatic genus of the family, Pipidae, occurring in Africa and distinguished by having black horny claws on three inner hind toes.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.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.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.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.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)Cell Line, Tumor: A cell line derived from cultured tumor cells.Cell Proliferation: All of the processes involved in increasing CELL NUMBER including CELL DIVISION.Nocodazole: Nocodazole is an antineoplastic agent which exerts its effect by depolymerizing microtubules.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.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.Protein Kinases: A family of enzymes that catalyze the conversion of ATP and a protein to ADP and a phosphoprotein.Cdh1 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.Oncogene Proteins: Proteins coded by oncogenes. They include proteins resulting from the fusion of an oncogene and another gene (ONCOGENE PROTEINS, FUSION).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.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.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.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.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.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.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.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.Cell Line: Established cell cultures that have the potential to propagate indefinitely.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.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.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.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.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.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.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.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.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).Ovum: A mature haploid female germ cell extruded from the OVARY at OVULATION.Cell Extracts: Preparations of cell constituents or subcellular materials, isolates, or substances.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.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.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).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.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.Immunohistochemistry: Histochemical localization of immunoreactive substances using labeled antibodies as reagents.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.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.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.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)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.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.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.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.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.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.Transcription Factors: Endogenous substances, usually proteins, which are effective in the initiation, stimulation, or termination of the genetic transcription process.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.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.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.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.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.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).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.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-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.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).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.G0 Phase: A quiescent state of cells during G1 PHASE.Embryo, Nonmammalian: The developmental entity of a fertilized egg (ZYGOTE) in animal species other than MAMMALS. For chickens, use CHICK EMBRYO.DNA Replication: The process by which a DNA molecule is duplicated.Time Factors: Elements of limited time intervals, contributing to particular results or situations.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.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.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.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)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.Polyploidy: The chromosomal constitution of a cell containing multiples of the normal number of CHROMOSOMES; includes triploidy (symbol: 3N), tetraploidy (symbol: 4N), etc.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.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.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.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.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.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.Aphidicolin: An antiviral antibiotic produced by Cephalosporium aphidicola and other fungi. It inhibits the growth of eukaryotic cells and certain animal viruses by selectively inhibiting the cellular replication of DNA polymerase II or the viral-induced DNA polymerases. The drug may be useful for controlling excessive cell proliferation in patients with cancer, psoriasis or other dermatitis with little or no adverse effect upon non-multiplying cells.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/)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.Fibroblasts: Connective tissue cells which secrete an extracellular matrix rich in collagen and other macromolecules.Ubiquitins: A family of proteins that are structurally-related to Ubiquitin. Ubiquitins and ubiquitin-like proteins participate in diverse cellular functions, such as protein degradation and HEAT-SHOCK RESPONSE, by conjugation to other proteins.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.S-Phase Kinase-Associated Proteins: A family of structurally-related proteins that were originally identified by their ability to complex with cyclin proteins (CYCLINS). They share a common domain that binds specifically to F-BOX MOTIFS. They take part in SKP CULLIN F-BOX PROTEIN LIGASES, where they can bind to a variety of F-BOX PROTEINS.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.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.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.Retinoblastoma-Like Protein p107: A negative regulator of the CELL CYCLE that undergoes PHOSPHORYLATION by CYCLIN-DEPENDENT KINASES. It contains a conserved pocket region that binds E2F4 TRANSCRIPTION FACTOR and interacts with viral ONCOPROTEINS such as POLYOMAVIRUS TUMOR ANTIGENS; ADENOVIRUS E1A PROTEINS; and PAPILLOMAVIRUS E7 PROTEINS.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.Recombinant Proteins: Proteins prepared by recombinant DNA technology.Ligases: A class of enzymes that catalyze the formation of a bond between two substrate molecules, coupled with the hydrolysis of a pyrophosphate bond in ATP or a similar energy donor. (Dorland, 28th ed) EC 6.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.Gene Expression: The phenotypic manifestation of a gene or genes by the processes of GENETIC TRANSCRIPTION and GENETIC TRANSLATION.Breast Neoplasms: Tumors or cancer of the human BREAST.Polyadenylation: The addition of a tail of polyadenylic acid (POLY A) to the 3' end of mRNA (RNA, MESSENGER). Polyadenylation involves recognizing the processing site signal, (AAUAAA), and cleaving of the mRNA to create a 3' OH terminal end to which poly A polymerase (POLYNUCLEOTIDE ADENYLYLTRANSFERASE) adds 60-200 adenylate residues. The 3' end processing of some messenger RNAs, such as histone mRNA, is carried out by a different process that does not include the addition of poly A as described here.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.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.Carrier Proteins: Transport proteins that carry specific substances in the blood or across cell membranes.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.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.Chromatids: Either of the two longitudinally adjacent threads formed when a eukaryotic chromosome replicates prior to mitosis. The chromatids are held together at the centromere. Sister chromatids are derived from the same chromosome. (Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)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.Tubulin Modulators: Agents that interact with TUBULIN to inhibit or promote polymerization of MICROTUBULES.Gene Expression Regulation, Developmental: Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action during the developmental stages of an organism.Ki-67 Antigen: A CELL CYCLE and tumor growth marker which can be readily detected using IMMUNOCYTOCHEMISTRY methods. Ki-67 is a nuclear antigen present only in the nuclei of cycling cells.3' Untranslated Regions: The sequence at the 3' end of messenger RNA that does not code for product. This region contains transcription and translation regulating sequences.Leupeptins: A group of acylated oligopeptides produced by Actinomycetes that function as protease inhibitors. They have been known to inhibit to varying degrees trypsin, plasmin, KALLIKREINS, papain and the cathepsins.Active Transport, Cell Nucleus: Gated transport mechanisms by which proteins or RNA are moved across the NUCLEAR MEMBRANE.Drosophila: A genus of small, two-winged flies containing approximately 900 described species. These organisms are the most extensively studied of all genera from the standpoint of genetics and cytology.Transcription Factor DP1: A transcription factor that possesses DNA-binding and E2F-binding domains but lacks a transcriptional activation domain. It is a binding partner for E2F TRANSCRIPTION FACTORS and enhances the DNA binding and transactivation function of the DP-E2F complex.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.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.Antineoplastic Agents: Substances that inhibit or prevent the proliferation of NEOPLASMS.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)Bivalvia: A class in the phylum MOLLUSCA comprised of mussels; clams; OYSTERS; COCKLES; and SCALLOPS. They are characterized by a bilaterally symmetrical hinged shell and a muscular foot used for burrowing and anchoring.Proto-Oncogene Proteins c-myc: Cellular DNA-binding proteins encoded by the c-myc genes. They are normally involved in nucleic acid metabolism and in mediating the cellular response to growth factors. Elevated and deregulated (constitutive) expression of c-myc proteins can cause tumorigenesis.Ubiquitin-Conjugating Enzymes: A class of enzymes that form a thioester bond to UBIQUITIN with the assistance of UBIQUITIN-ACTIVATING ENZYMES. They transfer ubiquitin to the LYSINE of a substrate protein with the assistance of UBIQUITIN-PROTEIN LIGASES.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.Retinoblastoma-Binding Protein 1: A ubiquitously expressed regulatory protein that contains a retinoblastoma protein binding domain and an AT-rich interactive domain. The protein may play a role in recruiting HISTONE DEACETYLASES to the site of RETINOBLASTOMA PROTEIN-containing transcriptional repressor complexes.Karyopherins: A family of proteins involved in NUCLEOCYTOPLASMIC TRANSPORT. Karyopherins are heteromeric molecules composed two major types of components, ALPHA KARYOPHERINS and BETA KARYOPHERINS, that function together to transport molecules through the NUCLEAR PORE COMPLEX. Several other proteins such as RAN GTP BINDING PROTEIN and CELLULAR APOPTOSIS SUSCEPTIBILITY PROTEIN bind to karyopherins and participate in the transport process.Cell Nucleus Division: The process by which the CELL NUCLEUS is divided.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).Protein-Tyrosine Kinases: Protein kinases that catalyze the PHOSPHORYLATION of TYROSINE residues in proteins with ATP or other nucleotides as phosphate donors.Cell Differentiation: Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.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.Antimitotic Agents: Agents that arrest cells in MITOSIS, most notably TUBULIN MODULATORS.Up-Regulation: A positive 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.Kinetin: A furanyl adenine found in PLANTS and FUNGI. It has plant growth regulation effects.Cell Transformation, Neoplastic: Cell changes manifested by escape from control mechanisms, increased growth potential, alterations in the cell surface, karyotypic abnormalities, morphological and biochemical deviations from the norm, and other attributes conferring the ability to invade, metastasize, and kill.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.Chromosome Segregation: The orderly segregation of CHROMOSOMES during MEIOSIS or MITOSIS.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.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.Potoroidae: A family of rat kangaroos found in and around Australia. Genera include Potorous and Bettongia.Proteolysis: Cleavage of proteins into smaller peptides or amino acids either by PROTEASES or non-enzymatically (e.g., Hydrolysis). It does not include Protein Processing, Post-Translational.Invertebrate Hormones: Hormones produced by invertebrates, usually insects, mollusks, annelids, and helminths.Transcriptional Activation: Processes that stimulate the GENETIC TRANSCRIPTION of a gene or set of genes.

The mitogen-activated protein kinase signaling pathway stimulates mos mRNA cytoplasmic polyadenylation during Xenopus oocyte maturation. (1/760)

The Mos protein kinase is a key regulator of vertebrate oocyte maturation. Oocyte-specific Mos protein expression is subject to translational control. In the frog Xenopus, the translation of Mos protein requires the progesterone-induced polyadenylation of the maternal Mos mRNA, which is present in the oocyte cytoplasm. Both the Xenopus p42 mitogen-activated protein kinase (MAPK) and maturation-promoting factor (MPF) signaling pathways have been proposed to mediate progesterone-stimulated oocyte maturation. In this study, we have determined the relative contributions of the MAPK and MPF signaling pathways to Mos mRNA polyadenylation. We report that progesterone-induced Mos mRNA polyadenylation was attenuated in oocytes expressing the MAPK phosphatase rVH6. Moreover, inhibition of MAPK signaling blocked progesterone-induced Mos protein accumulation. Activation of the MAPK pathway by injection of RNA encoding Mos was sufficient to induce both the polyadenylation of synthetic Mos mRNA substrates and the accumulation of endogenous Mos protein in the absence of MPF signaling. Activation of MPF, by injection of cyclin B1 RNA or purified cyclin B1 protein, also induced both Mos protein accumulation and Mos mRNA polyadenylation. However, this action of MPF required MAPK activity. By contrast, the cytoplasmic polyadenylation of maternal cyclin B1 mRNA was stimulated by MPF in a MAPK-independent manner, thus revealing a differential regulation of maternal mRNA polyadenylation by the MAPK and MPF signaling pathways. We propose that MAPK-stimulated Mos mRNA cytoplasmic polyadenylation is a key component of the positive-feedback loop, which contributes to the all-or-none process of oocyte maturation.  (+info)

p53 regulates a G2 checkpoint through cyclin B1. (2/760)

The p53 tumor suppressor controls multiple cell cycle checkpoints regulating the mammalian response to DNA damage. To identify the mechanism by which p53 regulates G2, we have derived a human ovarian cell that undergoes p53-dependent G2 arrest at 32 degrees C. We have found that p53 prevents G2/M transition by decreasing intracellular levels of cyclin B1 protein and attenuating the activity of the cyclin B1 promoter. Cyclin B1 is the regulatory subunit of the cdc2 kinase and is a protein required for mitotic initiation. The ability of p53 to control mitotic initiation by regulating intracellular cyclin B1 levels suggests that the cyclin B-dependent G2 checkpoint has a role in preventing neoplastic transformation.  (+info)

Activation of integrin and ceramide signalling pathways can inhibit the mitogenic effect of insulin-like growth factor I (IGF-I) in human breast cancer cell lines. (3/760)

Cell counting, cell cycle analysis and Western immunoblotting were used to examine the effects of non-apoptotic doses of a ceramide analogue, C2, and a synthetic arginine-glycine-aspartic acid (RGD)-containing peptide, RGD, in MCF-7 and T47D cells to determine whether activation of these signalling pathways could alter the mitogenic potential of insulin-like growth factor I (IGF-I). IGF-I alone increased total cell number in both cell lines, associated with a rise in the percentage of cells in the S-phase of the cell cycle and a co-incident increase in cyclin A production. Treatments alone had no effects on cell number or cyclin A production relative to controls. C2 inhibited IGF-I-induced mitogenesis in both lines, whereas RGD was only effective in the T47D line. Despite inhibition of cell proliferation, IGF-I stimulation of cells in S-phase and of cyclin A levels were unaffected; however, an IGF-I-induced increase in cyclin B1 levels was inhibited by 30%. Low-dose induction of integrin and ceramide signalling pathways causes cells to be blocked in S-phase, thereby inhibiting the normal cycle of events associated with the IGF-I-induced mitotic signal. Activating these pathways may not only restrict tumour growth by induction of apoptosis but they may also directly inhibit IGF-I-induced cell proliferation.  (+info)

Posttranslational regulation of the retinoblastoma gene family member p107 by calpain protease. (4/760)

The retinoblastoma protein plays a critical role in regulating the G1/S transition. Less is known about the function and regulation of the homologous pocket protein p107. Here we present evidence for the posttranslational regulation of p107 by the Ca2+-activated protease calpain. Three negative growth regulators, the HMG-CoA reductase inhibitor lovastatin, the antimetabolite 5-fluorouracil, and the cyclic nucleotide dibutyryl cAMP were found to induce cell type-specific loss of p107 protein which was reversible by the calpain inhibitor leucyl-leucyl-norleucinal but not by the serine protease inhibitor phenylmethylsulfonylfluoride, caspase inhibitors, or lactacystin, a specific inhibitor of the 26S proteasome. Purified calpain induced Ca2+-dependent p107 degradation in cell lysates. Transient expression of the specific calpain inhibitor calpastatin blocked the loss of p107 protein in lovastatin-treated cells, and the half-life of p107 was markedly lengthened in lovastatian-treated cells stably transfected with a calpastatin expression vector versus cells transfected with vector alone. The data presented here demonstrate down-regulation of p107 protein in response to various antiproliferative signals, and implicate calpain in p107 posttranslational regulation.  (+info)

Alteration in p53 pathway and defect in apoptosis contribute independently to cisplatin-resistance. (5/760)

The accumulation of molecular genetic defects selected during the adaptation process in the development of cisplatin-resistance was studied using progressive cisplatin-resistant variants (L1210/DDP2, L1210/DDP5, L1210/DDP10) derived from a murine leukemia cell line (L1210/0). Of these cell lines, only the most resistant L1210/DDP10 was cross-resistant to etoposide and deficient in apoptosis induced by these two drugs, indicating that resistance to DNA-damaging agents correlates with a defect in apoptosis. This defect was tightly associated with the loss of a Ca2+/Mg2+-dependent nuclear endonuclease activity present in the less cisplatin-resistant cells. Evidence is presented that p53-dependent function (a) is lost not only in the apoptosis defective L1210/DDP10 cells, but also in the apoptosis susceptible L1210/DDP5 cells; (b) is unrelated to drug-induced cell cycle perturbations. These results suggest that deficiency in the p53 pathway and resistance to DNA-damaging agents due to a defect in apoptosis are independent events.  (+info)

Cytoplasmic polyadenylation elements mediate masking and unmasking of cyclin B1 mRNA. (6/760)

During oocyte maturation, cyclin B1 mRNA is translationally activated by cytoplasmic polyadenylation. This process is dependent on cytoplasmic polyadenylation elements (CPEs) in the 3' untranslated region (UTR) of the mRNA. To determine whether a titratable factor might be involved in the initial translational repression (masking) of this mRNA, high levels of cyclin B1 3' UTR were injected into oocytes. While this treatment had no effect on the poly(A) tail length of endogenous cyclin B1 mRNA, it induced cyclin B1 synthesis. A mutational analysis revealed that the most efficient unmasking element in the cyclin 3' UTR was the CPE. However, other U-rich sequences that resemble the CPE in structure, but which do not bind the CPE-binding polyadenylation factor CPEB, failed to induce unmasking. When fused to the chloramphenical acetyl transferase (CAT) coding region, the cyclin B1 3' UTR inhibited CAT translation in injected oocytes. In addition, a synthetic 3' UTR containing multiple copies of the CPE also inhibited translation, and did so in a dose-dependent manner. Furthermore, efficient CPE-mediated masking required cap-dependent translation. During the normal course of progesterone-induced maturation, cytoplasmic polyadenylation was necessary for mRNA unmasking. A model to explain how cyclin B1 mRNA masking and unmasking could be regulated by the CPE is presented.  (+info)

Cyclic AMP delays G2 progression and prevents efficient accumulation of cyclin B1 proteins in mouse macrophage cells. (7/760)

In mouse macrophage cells, the increase of the intracellular cAMP level activates protein kinase A (PKA) and results in inhibition of cell cycle progression in both G1 and G2/M phases. G1 arrest is mediated by a cdk inhibitor, p27Kip1, which prevents G1 cyclin/cdk complexes from being activated in response to colony stimulating factor-1, whereas inhibition of G2/M progression has not been fully elucidated. In this report we analyzed the effect of cAMP on G2/M progression in a mouse macrophage cell line, BAC1.2F5A. Flow cytometric analysis and mitotic index measurement using both synchronized and asynchronized cells revealed that addition of cAMP-elevating agents (8-bromoadenosine 3':5'-cyclic monophosphate and 3-isobutyl-methyl-xanthine), although they did not affect S phase progression or M/G1 transition, temporarily arrested cells in G2 but eventually the cells proceeded to M phase, resulting in about 4 hours delay of G2 progression. Timing of cyclin B1/Cdc2 kinase activation was also retarded by about 4 hours, which was accompanied by inhibition of efficient accumulation of cyclin B1 proteins. Initial induction and accumulation of cyclin B1 mRNA were not hampered, but the half life of cyclin B1 proteins was significantly shorter during G2 phase in the presence of cAMP-elevating agents compared with that of the cells blocked from progressing through M phase by nocodazole. These results imply that the cAMP/PKA pathway regulates G2 phase progression by altering the stability of a crucial cell cycle regulator.  (+info)

Cytoplasmic localization of human cdc25C during interphase requires an intact 14-3-3 binding site. (8/760)

cdc25C induces mitosis by activating the cdc2-cyclin B complex. The intracellular localization of cyclin B1 is regulated in a cell cycle-specific manner, and its entry into the nucleus may be required for the initiation of mitosis. To determine the cellular localization of cdc25C, monoclonal antibodies specific for cdc25C were developed and used to demonstrate that in human cells, cdc25C is retained in the cytoplasm during interphase. A deletion analysis identified a 58-amino-acid region (amino acids 201 to 258) in cdc25C that was required for the cytoplasmic localization of cdc25C. This region contained a specific binding site for 14-3-3 proteins, and mutations in cdc25C that disrupted 14-3-3 binding also disrupted the cytoplasmic localization of cdc25C during interphase. cdc25C proteins that do not contain a binding site for 14-3-3 proteins showed a pancellular localization and an increased ability to induce premature chromosome condensation. The cytoplasmic localization of cdc25C was not altered by gamma irradiation or treatment with the nuclear export inhibitor leptomycin B. These results suggest that 14-3-3 proteins may negatively regulate cdc25C function by sequestering cdc25C in the cytoplasm.  (+info)

10 products from 6 suppliers. Compare and order Cyclin B1 ELISA Kits. View citations, images, detection ranges, sensitivity, prices and more. Recommended products for the most popular species. Our scientists will help you find the right ELISA kit for your needs.
Wee1 acts as a negative regulator of entry into mitosis (G2 to M transition) by protecting the nucleus from cytoplasmically activated cyclin B1-complexed CDK1 before the onset of mitosis. The activity of wee1 increases during the S and G2 phases, and decreases in M phase when it is hyperphosphorylated. A correlated decrease in wee1 protein level occurs at M/G1 phase, probably due to its degradation. Wee1 specifically phosphorylates and inactivates cyclin B1-complexed CDK1 reaching a maximum during G2 phase and a minimum as cells enter M phase. The phosphorylation of cyclin B1-CDK1 occurs exclusively on Tyr-15 and phosphorylation of monomeric CDK1 does not occur ...
CCNB2 Human Recombinant produced E. coli is a single polypeptide chain containing 422 amino acids (1-398) and having a molecular mass of 47.9 kDa.
Complete information for CCNB2 gene (Protein Coding), Cyclin B2, including: function, proteins, disorders, pathways, orthologs, and expression. GeneCards - The Human Gene Compendium
Reactome is pathway database which provides intuitive bioinformatics tools for the visualisation, interpretation and analysis of pathway knowledge.
Reactome is pathway database which provides intuitive bioinformatics tools for the visualisation, interpretation and analysis of pathway knowledge.
NU6102, CDK1/cyclin B and CDK2/cyclin A3 inhibitor (CAS 444722-95-6), with |98% purity. Join researchers using our high quality biochemicals.
We investigated the occurrence of transcription during mitosis on an RNA pol II‐transcribed gene. We have found that the human cyclin B1 gene is actively transcribed at the mitotic stage. This result is surprising, since it is widely accepted that transcription is repressed during mitosis in higher eukaryotes. Interestingly, in fission yeast the rate of RNA synthesis is maintained during passage through mitosis (Baum et al., 1998). In mammalian cells, until now, no RNA pol II‐dependent transcription has been reported in mitotic cells, although there is evidence showing that 10-20% of the TFIID population remains associated with the condensed mitotic chromatin (Segil et al., 1996). Whether the transcription of the cyclin B1 gene occurs during all the four mitosis phases remains to be elucidated. The cyclin B1 protein is quickly degraded at the metaphase. Whenever a spindle checkpoint is imposed during metaphase, there is a reappearance of cyclin B1 protein due to a loss of cyclin B1 ...
Manni I., Tunici P., Cirenei N., Albarosa R., Colombo B.M., Roz L., Sacchi A., Piaggio G., Finocchiaro G.. Mxi1 is a Mad family member that plays a role in cell proliferation and differentiation. To test the role of Mxi1 on tumorigenesis of glioma cells we transfected a CMV-driven MXI1 cDNA in U87 human glioblastoma cells. Two clones were isolated expressing MXI1 levels 18- and 3.5-fold higher than wild-type U87 cells (clone U87.Mxi1.14 and U87.Mxi1.22, respectively). In vivo, U87.Mxi1.14 cells were not tumorigenic in nude mice and delayed development of tumours was observed with U87.Mxi1.22 cells. In vitro, the proliferation rate was partially and strongly inhibited in U87.Mxi1.22 and U87.Mxi1.14 cells respectively. The cell cycle analysis revealed a relevant accumulation of U87.Mxi1.14 cells in the G(2)/M phase. Interestingly, the expression of cyclin B1 was inhibited to about 60% in U87.Mxi1.14 cells. This inhibition occurs at the transcriptional level and depends, at least in part, on the ...
Cell Cycle, Genes, Tumor, Cell Cycle Genes, Human, Repression, Gene, Dream, Proteins, Regulation, Cell, Cyclin, Cyclin B2, Elements, Mitosis, DNA, Family, Transcription Factors, Apoptosis, DNA Damage
amp;amp;amp;amp;amp;amp;amp;amp;lt;div><img src="https://mc.yandex.ru/watch/35930735" style="position:absolute; left:-9999px;" alt="" /></div&gt ...
Fertilization of metaphase II-arrested mouse eggs results in resumption of meiosis and a decrease in both cdc2/cyclin B kinase and MAP kinase activities; the decrease in cdc2/cyclin B kinase activity precedes the decrease in MAP kinase activity. Cycloheximide treatment of metaphase II-arrested mouse eggs also results in resumption of meiosis but bypasses the fertilization-induced Ca2+ transient. However, it is not known if cycloheximide treatment results in the same temporal changes in cdc2/cyclin B kinase and MAP kinase activities that are intimately associated with resumption of meiosis. We report that cycloheximide-treated mouse eggs manifest similar temporal changes in the decrease in both cdc2/cyclin B kinase and MAP kinase activities that occur following fertilization, although cortical granule exocytosis is not stimulated. The decrease in cdc2/cyclin B kinase activity, however, does not seem to be required for the decrease in MAP kinase activity, since the decrease in MAP kinase activity ...
Activation of the Cyclin B/Cdc2 kinase complex triggers entry into mitosis in all eukaryotic cells. Cyclin B1 localization changes dramatically during the cell cycle, precipitously transiting from the cytoplasm to the nucleus at the beginning of mitosis. Presumably, this relocalization promotes the phosphorylation of nuclear targets critical for chromatin condensation and nuclear envelope breakdown. We show here that the previously characterized cytoplasmic retention sequence of Cyclin B1, responsible for its interphase cytoplasmic localization, is actually an autonomous nuclear export sequence, capable of directing nuclear export of a heterologous protein, and able to bind specifically to the recently identified export mediator, CRM1. We propose that the observed cytoplasmic localization of Cyclin B1 during interphase reflects the equilibrium between ongoing nuclear import and rapid CRM1-mediated export. In support of this hypothesis, we found that treatment of cells with leptomycin B, which ...
When the APC complex was inhibited by siRNA of APC3, the level of BubR1 remained constant for 60 min after nocodazole release in the presence of CHX, whereas it declined in control cells (Figure 8B). This result was corroborated by the finding from live‐cell assay for proteolysis that depleting APC3 expression abrogated the degradation of BubR1, and concomitantly cells did not enter anaphase for more than 5 h (Supplementary Figure 12 and Supplementary movie 7). When we compared the timing of BubR1 degradation with the degradation of other players in mitosis, such as Cdc20, Cyclin B, Plk1, and Aurora A, we found that BubR1 degradation began before that of Cyclin B (Supplementary Figure 13).. Next, we tested whether Cdc20 was responsible for BubR1 degradation during mitosis. To prevent the cells from exiting mitosis before the analysis began, HeLa cells were transfected with an expression construct to force moderate expression of Cyclin B. siRNA for GFP, Cdc20, or Cdh1 was simultaneously ...
Sea urchin eggs exhibit a cap-dependent increase in protein synthesis within minutes after fertilization. This rise in protein synthesis occurs at a constant rate for a great number of proteins translated from the different available mRNAs. Surprisingly, we found that cyclin B, a major cell-cycle regulator, follows a synthesis pattern that is distinct from the global protein population, so we developed a mathematical model to analyze this dissimilarity in biosynthesis kinetic patterns. The model includes two pathways for cyclin B mRNA entry into the translational machinery: one from immediately available mRNA (mRNAcyclinB) and one from mRNA activated solely after fertilization (XXmRNAcyclinB). Two coefficients, α and β, were added to fit the measured scales of global protein and cyclin B synthesis, respectively. The model was simplified to identify the synthesis parameters and to allow its simulation. The calculated parameters for activation of the specific cyclin B synthesis pathway after
The aim of this thesis was to investigate the prognostic role of the proliferation markers cyclin B1 and Phosphorylated Histone 3 (PPH3) in breast cancer (BC).. In paper I we used an experimental study design, we compared women dying early from their BC with women free from relapse more than eight years after initial diagnosis. All women had stage I, node-negative and hormone receptor positive disease. None had received adjuvant chemotherapy. We found that low-risk node negative patients with high expression of cyclin B1 had a significantly worse outcome than patients with low expression of cyclin B1.. In paper II a population-based case control study was performed to further investigate the prognostic value of cyclin B1. One hundred and ninety women who died from BC were defined as cases and 190 women alive at the time for the corresponding cases death were defined as controls. Inclusion criteria were tumor size 50 mm, no lymph node metastases, and no adjuvant chemotherapy. Two investigators ...
For example, in frogs, cyclin dependent protein kinase 2 (CDK2) binds to cyclin B to form an active kinase which phosphorylates a prereplication complex initiating S phase and mitosis. Cyclin B, a 45Kd protein, accumulates to high levels just before S phase. Its concentration drops sharply at the end of mitosis. The kinase, a 34 Kd protein, is encoded by the CDC2 gene (for cell division cycle gene). A homologous gene exists in humans - the CDK2 gene (cyclin dependent kinase 2) - and controls entry in S phase. These kinases can be considered heterodimers with a kinase catalytic subunit and a cyclin regulatory subunit. In animal cells, there are at least ten different cyclins (A, B, .....) and at least eight different cyclin-dependent kinases (CDK1-8). Another Look at Neurotransmission and Ion Channels. You may have noticed above that some signaling molecules, whose effects are regulated by kinases (b-adrenergic and some olfactory signals by PKA and acetylcholine by PKC for example), are ...
近 几年我们针对癌细胞中的标靶基因survivin及securin等,进行深入的研究。例如多种人类癌细胞(包括肺癌、乳癌、大肠癌及子宫颈癌等)会大量 表达survivin蛋白,但在正常成人细胞不会表达survivin。Survivin蛋白具有抗细胞凋亡及促细胞分裂的功能,调控癌细胞中 survivin蛋白的表达,与癌症的发生有密切的关系,而抑制survivin蛋白的表达,也可能应用于治疗癌症。我们建立了cyclin B1/cdc2与p38 MAP kinase可分别为正调控及负调控survivin基因及蛋白的表现(Chao et al., 2004, JBC)。此外,利用共轭焦显微镜及免疫萤光染色,建立survivin蛋白会大量表达于癌细胞之有丝分裂期,并会聚集于细胞质分裂期的midbody位 置(Kuo et al., 2004, JBC)。同时我们发现将survivin基因阻断,会促进抗癌药物抑制癌细胞的生长及促细胞凋亡之作用(Chao and Liu, 2006, Mol. ...
Rabbit polyclonal antibody raised against synthetic phosphopeptide of CCNB1. Synthetic phosphopeptide corresponding to residues surrounding S147 of human CCNB1. (PAB25912) - Products - Abnova
The cyclin E oncogene activates CDK2 to drive cells from G1 to S phase of the cell cycle to commence DNA replication. It coordinates essential cellular functions with the cell cycle including histone biogenesis, splicing, centrosome duplication and origin firing for DNA replication. The two E-cyclins, E1 and E2, are assumed to act interchangeably in these functions. However recent reports have identified unique functions for cyclins E1 and E2 in different tissues, and particularly in breast cancer. Cyclins E1 and E2 localise to distinct foci in breast cancer cells as well as co-localising within the cell. Both E-cyclins are found in complex with CDK2, at centrosomes and with the splicing machinery in nuclear speckles. However cyclin E2 uniquely co-localises with NPAT, the main activator of cell-cycle regulated histone transcription. Increased cyclin E2, but not cyclin E1, expression is associated with high expression of replication-dependent histones in breast cancers. The preferential localisation of
TY - JOUR. T1 - Hydrogen peroxide induces Sp1 methylation and thereby suppresses cyclin B1 via recruitment of Suv39H1 and HDAC1 in cancer cells. AU - Chuang, Jian Ying. AU - Chang, Wen Chang. AU - Hung, Jan Jong. PY - 2011/12/15. Y1 - 2011/12/15. N2 - Sp1 is an important transcription factor for a number of genes that regulate cell growth and survival. Sp1 is an anchor protein that recruits other factors to regulate its target genes positively or negatively, but the mechanism of its functional switch by which positive or negative coregulators are recruited is not clear. In this study, we found that Sp1 could be methylated and that methylation was maintained by treatment with pargyline, a lysine-specific demethylase 1 (LSD1) inhibitor or knock LSD1 down directly. Hydrogen peroxide treatment increased the methylation of Sp1 and repressed Sp1 transcriptional activity. Investigation of the mechanism by which methylation decreased Sp1 activity found that methylation of Sp1 increased the recruitment ...
The key conceptual move, as a biology student, is to be able to see how this system enables the cell (which of course doesnt have any consciousness or intention) to control its passage through the cell cycle every time it needs to divide. A new daughter cell will have very low cyclin levels, which includes the level of the cyclin weve been focused on, cyclin B. As the cell grows and it moves through G1, S, and G2, its level of cyclin B will rise. At a certain concentration of cyclin B, enough MPF is formed to enable to cell to enter M phase. But just at the same moment that the machinery for mitosis and cytokinesis is put into place, cyclin disintegrates. As a result, when the new daughter cells begin their independent existence, cyclin levels are once again very low…setting the stage for another cell cycle.. Note that in addition to these internal signals, external signals also influence cell division. For example, PDGF (platelet derived growth factor) stimulates a variety of cells to ...
Ccnb1ip1 - mouse gene knockout kit via CRISPR, 1 kit. |dl||dt|Kit Component:|/dt||dd|- |strong|KN302805G1|/strong|, Ccnb1ip1 gRNA vector 1 in |a href=http://www.origene.com/CRISPR-CAS9/Detail.
臺大位居世界頂尖大學之列,為永久珍藏及向國際展現本校豐碩的研究成果及學術能量,圖書館整合機構典藏(NTUR)與學術庫(AH)不同功能平台,成為臺大學術典藏NTU scholars。期能整合研究能量、促進交流合作、保存學術產出、推廣研究成果。. To permanently archive and promote researcher profiles and scholarly works, Library integrates the services of "NTU Repository" with "Academic Hub" to form NTU Scholars.. ...
The activation of the ubiquitin ligase APC/C requires the phosphorylation of multiple subunits. Because depletion or inactivation of the Xenopus Polo-like kinase 1 (Plx1) in meiotically arrested egg extracts blocks APC/C-dependent degradation of cyclin B ( 5), many investigators have tried to directly link the activities of Plk1 and APC/C. Although Plk1 is able to phosphorylate subunits of the APC/C in vitro, this phosphorylation contributes only marginally to its activation ( 6). In contrast, cyclin B/Cdk1 seems to have a major role in the phosphorylation and activation of the APC/C, thereby triggering its own inactivation at the end of mitosis ( 7).. Although Plk1 can contribute synergistically to the cyclin B/Cdk1-mediated activation of the APC/C ( 6), this observation is not sufficient to explain the crucial role of Plk1/Plx1 in the activation of the APC/C. Intriguing insights have come from studies of the cytostatic factor (CSF) in Xenopus oocytes, where CSF activity prevents parthogenetic ...
To determine whether Trim39 could inhibit the APC/C, we added either maltose-binding protein (MBP) or MBP-Trim39 protein to lysates prepared from HeLa cells that had been synchronized in nocodazole and then released (by washout of the nocodazole). As shown in Fig. 1 C, cyclin B1 was quickly degraded in the presence of recombinant MBP protein as these lysates exited from the mitotic arrest, whereas degradation of endogenous cyclin B1 was nearly abolished by addition of recombinant MBP-Trim39. This inhibition was not observed using the C44A mutant, suggesting that E3 ubiquitin ligase activity is required for APC/C inhibition (Fig. 1 C). Indeed, cyclin B1 was more rapidly degraded in the presence of the catalytically inactive Trim39 mutant, suggesting that this protein might interfere with the functioning of the endogenous protein. To confirm a direct role for Trim39 in APC/C inhibition, we incubated APC/C immunoprecipitated from HeLa cells with MBP or MBP-Trim39, E1, E2, ubiquitin, and ...
The effect was found to be associated with increased expression of E2F-1 in cervical cancer cells as there is no CAPE-mediated induction of E2F-1 in the precancerous cervical Z172 cells. CAPE also upregulated the E2F-1 target genes cyclin A, cyclin E, and apoptotic protease activation of factor 1 (Apaf-1) but down regulated cyclin B and myeloid leukemia cell differentiation protein (Mcl-1). These results suggested the involvement of E2F-1 in CAPE-mediated growth inhibition and cell cycle arrest. Transient transfection studies with luciferase reporters revealed that CAPE altered transcriptional activity of the apaf-1 and mcl-1 promoters. Further studies using chromatin immunoprecipitation (ChIP) assays demonstrated that in CAPE-treated cells, E2F-1 binding to the apaf-1 and cyclin B promoters was increased and decreased, respectively. Furthermore, E2F-1 silencing abolished CAPE-mediated effects on cell cycle arrest, apoptosis, and related gene expression ...
We report the isolation of UME3, a C‐type cyclin that is required for the full repression of several early meiotic genes (e.g. SPO13) and SSA1, a member of the HSP70 superfamily. Similarly to other cyclin C family members, UME3 mRNA and protein levels remained unchanged throughout the mitotic cell cycle. However, under conditions that induce SSA1 or SPO13 transcription, we demonstrate that Ume3p is subjected to degradation. This destruction is required for normal meiotic gene induction, as a mutation that stabilizes Ume3p resulted in a 2‐fold reduction in SPO13 mRNA accumulation. These findings reveal the first observed regulation of a C‐type cyclin. Moreover, the destruction of Ume3p in response to heat shock or developmental cues represents a new set of regulatory signals by which any cyclin is controlled. We identified three cis‐acting domains (PEST‐rich, RXXL and the cyclin box) that contribute to the destruction of Ume3p during heat shock. In cultures exposed to heat shock, Ume3p ...
Natural borneol (NB) has been used as a promoter of drug absorption and widely used in candies, beverages, baked goods, chewing gum and other foods. Thus, we investigated whether NB could potentiate the cellular uptake of BDCur, and elucidated the molecular mechanisms of their combined inhibitory effects on HepG2 cells. Our results demonstrate that NB significantly enhanced the cellular uptake of BDCur. Induction of cell cycle arrest in HepG2 cells by NB and BDCur in combination was evidenced by accumulation of the G2/M cell population. Further investigation on the molecular mechanism showed that NB and BDCur in combination resulted in a significant decrease in the expression level of Cdc2 and cyclin B ...
Sigma-Aldrich offers abstracts and full-text articles by [Eunju Kim, Se-Jin Yoon, Eun-Young Kim, Yunna Kim, Hyun-Seo Lee, Kyeoung-Hwa Kim, Kyung-Ah Lee].
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Breast cancer is one of the most common malignancies in women. Due to early detection and the use of screening programs approximately 60% of all new cases lack lymph node involvement. Today, a substantial proportion of these women will be offered adjuvant systemic chemotherapy. However, better proliferation markers are needed to predict patient outcome and to avoid overtreatment. Cyclin A, cyclin E and Ki-67 are all markers for proliferation and involved in the regulation of the cell cycle. Overexpression has been associated with disease recurrence in several studies, but the results have not been consistent. However, none of these studies has investigated aberrant expression of cyclin E (the expression of cyclin E during phases of the cell cycle other than late G1 and early S-phase). Studies have shown that aberrant cyclin E might provide additional prognostic information compared to cyclin E alone.. The aims of this thesis were 1.to investigate the prognostic value of cyclin A, cyclin E and ...
Our experiments demonstrate the existence of a complex containing both cyclin E and several components of the U2 snRNP in vivo, in particular SAP 155, SAP 145, and SAP 114. We were able to detect the association between both cyclin E and SAP 155, as well as cdk2 and SAP 155, through either of the components in cellular lysates. The cyclin E-SAP 155 association can also be shown in the yeast two-hybrid system and can be reconstituted in vitro by using recombinant components. Furthermore, we found that cyclin E-specific antibodies were able to precipitate U1 and U2 snRNAs, as well as the pre-mRNA substrate from preassembled spliceosomes.. We find that one component of U2 snRNP, SAP 155, serves as an excellent substrate for cyclin E-cdk2 both in the U2/E/k2 complex precipitated from cells and as a recombinant protein in vitro. Phosphorylation of SAP 155 in the U2/E/k2 complex can be inhibited by preincubation of these complexes with p21, a known cyclin-kinase inhibitor. Taken together, these data ...
Cyclin F兔多克隆抗体(ab123601)可与人样本反应并经WB实验严格验证。中国75%以上现货,所有产品均提供质保服务,可通过电话、电邮或微信获得本地专属技术支持。
マウス・モノクローナル抗体 ab38 交差種: Ms,Rat,Hu 適用: WB,IP,IHC-P,IHC-Fr,Flow Cyt…Cyclin A2抗体一覧…画像、プロトコール、文献などWeb上の情報が満載のアブカムの Antibody…
Dalby, B. and Glover, D. M. (1993). Discrete sequence elements control posterior pole accumulation and translational repression of maternal cyclin B RNA in Drosophila. EMBO J 12: 1219-27 DAngiolella, V., et al. (2001). Role for cyclin-dependent kinase 2 in mitosis exit. Curr. Bio. 11: 1221-1226. 11516956 de Moor, C. H. and Richter, J. D. (1999). Cytoplasmic polyadenylation elements mediate masking and unmasking of cyclin B1 mRNA. EMBO J. 18(8): 2294-2303 Detweiler, C. S. and Li, J. J. (1998). Ectopic induction of Clb2 in early G1 phase is sufficient to block prereplicative complex formation in Saccharomyces cerevisiae. Proc. Natl. Acad. Sci. 95(5): 2384-9 Dawson, I. A., Roth, S. and Artavanis-Tsakonas, S. (1995). The Drosophila cell cycle gene fizzy is required for normal degradation of cyclins A and B during mitosis and has homology to the CDC20 gene of Saccharomyces cerevisiae. J Cell Biol 129: 725-737 Dulic, V., et al. (1998). Nuclear accumulation of p21Cip1 at the onset of mitosis: a role ...
The representation of cyclins and cyclin-dependent kinases (cdks) was analyzed during progressive development of the bone cell phenotype in cultures of normal diploid rat calvarial osteoblasts. Three developmental stages were examined: (a) proliferation; (b) monolayer confluency; and (c) mineralization of the bone extracellular matrix. We demonstrate that the presence of cyclins and cdks is not restricted to the proliferation period. Consistent with their role in cell cycle progression, cdc2 and cdk2 decrease postproliferatively. However, cdk4 and cyclins A, B, and D1 persist in confluent cells. Cyclin E is significantly up-regulated during the extracellular matrix mineralization developmental period. Examination of the cytoplasmic levels of these cell cycle regulatory proteins indicates a marked increase in cyclin B in the late differentiation stage. The elevation of nuclear cyclin E and cytoplasmic cyclin B is not observed in osteoblasts maintained under culture conditions that do not support
Methods and results: Levels of FOXM1 and its targets were determined by immunoprecipitation and real-time PCR analyses in rat and human samples. FOXM1 function was investigated by either FOXM1 silencing or overexpression in human HCC cell lines. Activation of FOXM1 and its targets (Aurora Kinose A, Cdc2, cyclin B1, Nek2) occurred earlier and was most pronounced in liver lesions from F344 than BN rats, leading to the highest number of Cdc2-cyclin B1 complexes (implying the highest G2-M transition) in F344 rats. In human HCC, the level of FOXM1 progressively increased from surrounding non-tumorous livers to HCC, reaching the highest levels in tumours with poorer prognosis (as defined by patients length of survival). Furthermore, expression levels of FOXM1 directly correlated with the proliferation index, genomic instability rate and microvessel density, and inversely with apoptosis. FOXM1 upregulation was due to extracellular signal-regulated kinase (ERK) and glioblastoma-associated oncogene 1 ...
Entry into mitosis in Aspergillus nidulans is regulated by the coordinate function of two serine/threonine protein kinases, NIMXCDC2 and NIMA. NIMXCDC2 is an essential histone H1 kinase that is structurally and functionally homologous to fission yeast p34cdc2 (Osmani et al., 1994). NIMA is a β-casein kinase and is structurally distinct from p34cdc2, containing an amino-terminal catalytic domain and a carboxyl-terminal regulatory domain (Osmani et al., 1988b; Lu et al., 1993; Pu and Osmani, 1995; Pu et al., 1995). Failure to properly activate either of these kinases in G2 prevents the initiation of mitosis, and the combined action of both kinases is critical for coordinating changes in chromosome, microtubule, and nuclear membrane structure during mitosis. For example, mutations preventing the activation of NIMXCDC2 in G2 normally arrests cells in late G2 (Osmani et al., 1991a; 1994). Although overexpression of NIMA can overcome this interphase arrest, the ensuing mitosis is disorganized such ...
DAT-230 is a promising microtubule inhibitor that has great potential for the treatment of fibrosarcoma in vitro and in vivo. DAT-230 exhibited potent anti-proliferative activity against various cancer cells. DAT-230 -treatment in HT-1080 cells resulted in microtubule de-polymerization and G2/M phase arrest preceding apoptosis. Phosphor-cdc2 (thr14/tyr15) reduction, cyclin B1 accumulation and aberrant spindles denoted the cyclin B1-cdc2 complex active and M phase arrest in HT-1080 cells treated with DAT-230. Apoptosis induced by DAT-230 was related with the activation of caspase-9, caspase-3 and PARP cleavage, which were at the downstream of mitochondria.
In humans, there are two A-type cyclins - an embryonic-specific cyclin A1 and a somatic cyclin A2. Cyclin A1 is only expressed in meiosis and very early embryos, whereas cyclin A2 is present in proliferating somatic cells
购买经敲除验证的重组Cyclin D1兔单克隆抗体[EP272Y](ab40754),Cyclin D1抗体经WB,IP验证,可与人,小鼠,大鼠样本反应。8篇文献引用,4个独立用户反馈。
Cyclin D1 expression is induced by Sox17.(A-B) Immunohistochemistry for cyclin D1 was performed on lung sections from adult CCSPrtTA (A) and CCSPrtTA/tetO-Sox
... , Authors: Immacolata Vocca, Gianmarco Muzi, Francesca Pentimalli, Antonio Giordano. Published in: Atlas Genet Cytogenet Oncol Haematol.
Meiosis in mammalian oocytes is driven by changes in the activity of maturation-promoting factor (MPF). MPF activity is attributed entirely to the activity of the universal mitotic kinase, cdk1-cyclin B (Draetta et al., 1989; Labbe et al., 1989; Gautier et al., 1990). In mammals, oocytes are arrested in prophase of meiosis I with low levels of MPF (Hashimoto and Kishimoto, 1986; Choi et al., 1991). An increase in MPF activity stimulates entry into M phase of meiosis I, the first sign of which is germinal vesicle (GV) breakdown (GVBD), which takes place ∼90 min after release from the follicle. Continued cyclin B synthesis and increasing levels of MPF drive the oocyte to metaphase of the first meiotic division (Tay et al., 2000; Ledan et al., 2001), which is followed by polar body extrusion 7-9 h after GVBD. After MI, the oocyte proceeds immediately to meiosis II, where it arrests with high levels of MPF activity that are stabilized by cytostatic factor (CSF; Masui and Markert, 1971; Hashimoto ...
Meiosis, the pair of specialized cell divisions required to convert germline diploid progenitor cells into haploid gametes, is an essential process for sexual reproduction in eukaryotes. After pre-meiotic DNA replication, germ cells enter an extended G2 cell cycle phase, termed meiotic prophase, during which homologous chromosomes pair and interact, and an extensive, cell type-specific transcription program turns on to set up gamete differentiation. The homologs then segregate to different daughter cells, commonly during the first meiotic division, followed by segregation of sister chromatids during meiosis II without an intervening S phase. As in mitosis, the timing of key cell cycle events is choreographed by regulated activation and deactivation of cyclin-dependent kinase (Cdk) complexes, in which cyclins play key roles in regulating the timing and targets of Cdk activity. B-type cyclins in particular are instrumental to negotiating the G2/M transition in both mitosis and meiosis.. The ...
Looking for online definition of Cyclin F in the Medical Dictionary? Cyclin F explanation free. What is Cyclin F? Meaning of Cyclin F medical term. What does Cyclin F mean?
Cardiomyocytes cease to divide shortly after birth and an irreversible cell cycle arrest is evident accompanied by the downregulation of cyclin-dependent kinase activities. To get a better understanding of the cardiac cell cycle and its regulation, the effect of functional recovery of the mitosis-promoting factor (MPF) consisting of cyclin B1 and the cyclin-dependent kinase Cdc2 was assessed in primary cultures of postmitotic ventricular adult rat cardiomyocytes ( ARC). Gene transfer into ARC was achieved using the adenovirus-enhanced transferrinfection system that was characterized by the absence of cytotoxic events. Simultaneous ectopic expression of wild-type versions of cyclin B1 and Cdc2 was sufficient to induce MPF activity. Reestablished MPF resulted in a mitotic phenotype, marked by an abnormal condensation of the nuclei, histone H3 phosphorylation and variable degree of decay of the contractile apparatus. Although a complete cell division was not observed, the results provided ...
Cyclin N1 has an important function in the control of cellular growth and its phrase is certainly activated during gastrulation in the mouse, however, it remains to be unknown how phrase is controlled during early embryonic advancement. that facilitates account activation of cyclin N1 phrase during Ha sido cell difference. Components AND Strategies Ha sido cell lines and difference and embryos Crazy type and knockout ((Body 1B). growth of both Ha sido cell types was also examined by shot of undifferentiated and differentiated (chemical3 and chemical6) wt or gene phrase in differentiated GCNF?/? Ha sido cells and the down control of March4 in wt Ha 143257-98-1 sido cells (Body 1D). Maintenance of an undifferentiated morphology is certainly most most likely triggered by the phrase of fairly high amounts of pluripotency genetics in differentiated phrase continued to be at low amounts during phrase breaks down to 143257-98-1 activate cyclin N1 phrase. (A) mRNA was singled out from wt Ha sido cells ...
E, CAL120 cells were either untreated or pretreated with gemcitabine for 24 hours followed by treatment with AZD7762 and /or MK-1775 for an additional 2 hours (top) or 8 hours (bottom), before lysis. Western blot analysis of Cyclin B1, CDK1 (phospho-Y15 and total) expression, and β-tubulin as loading control. F, induction of the intra-S-phase checkpoint was not affected by WEE1 inhibition. CAL120 cells were pulse-labeled with 10 μmol/L BrdU for 30 minutes, washed (W), and then treated with 1 μmol/L camptothecin (CPT) for 30 minutes. After CPT removal (0 hours), BrdU-labeled S-phase cells (BrdU+ , indicated by boxed area) were monitored at the indicated time points in the absence (iii) or presence of MK-1775 (iv) or AZD7762 as a positive control (v). Control cells (ctr) were not exposed to CPT and cultured in the absence (i) or presence of MK-1775 (ii). Arrowheads indicate delayed S-phase progression.. ...
View mouse Ccndbp1 Chr2:121008403-121016904 with: phenotypes, sequences, polymorphisms, proteins, references, function, expression
Supplemental Figure 2 - Fig. S2. Quantification of effects on cells after CAP-D2 RNAi. (A) Growth curve showing the number of cells at different time points after CAP-D2 dsRNA treatment. Cells grew more slowly, plateaued at 72 hours, and did not change significantly after that time. (B) The percentage of mitotic cells in control and CAP-D2 RNAi cells. The percentage of mitotic cells increased two- to threefold in the CAP-D2 RNAi between 36 and 72 hours (6.7% versus 2.2% at 48 hours). (C) The percentage of abnormal mitotic cells in control and CAP-D2 RNAi cells. The majority of mitotic cells are abnormal 36 hours and later after dsRNAi treatment. (D) Histogram showing the percentage of cells in prometaphase after staining for Cyclin B/P-H3/a-tubulin in control and CAP-D2 RNAi cells. Cells delay in prometaphase in the CAP-D2-depleted cells. (E) Histogram showing the percentage of cells in anaphase after staining for Cyclin B/P-H3/a-tubulin, in control and CAP-D2 RNAi cells. The anaphase index in ...
In this study, we have analyzed the role of RPA in cell cycle progression in the Drosophila optic lobe and found that loss of RPA function causes premature differentiation of NE cells into medulla NBs. Furthermore, inactivation of the core cell cycle regulators in NE cells, including E2F1, Cyclin E, PCNA, Cyclin A, Cyclin B, Cdk1, and Cdk2, each also caused the precocious NE-to-NB transition. Thus, our data indicate that inhibition of NE cell cycle progression is causally linked with the transition of symmetric proliferative division to asymmetric neurogenic division in the optic lobe neuroepithelium and this transition is likely achieved through Numb-mediated downregulation of Notch signaling activity.. The RPA complex encodes highly conserved proteins involved in a variety of DNA metabolism, including DNA replication, DNA repair, and recombination processes (Wold, 1997; Iftode et al., 1999; Binz et al., 2004; Bochkarev and Bochkareva, 2004). However, a role of any of these RPA components in ...
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Whereas many components regulating the progression from S phase through G2 phase into mitosis have been identified, the mechanism by which these components control this critical cell cycle progression is still not fully elucidated. Cyclin A/Cdk2 has
References for Abcams Recombinant Human Cyclin E1 protein (ab119719). Please let us know if you have used this product in your publication
Fig. S3 (a, c) Melanoma cells were treated with 1 μg/ml cisplatin or 250 μg/ml dacarbazine and harvested at various time-points. And the menin expression was determined with Western blotting. (b, d) Melanoma cells were treated with the indicated concentrations of cisplatin or dacarbazine, and the menin expression was detected by Western blotting. (e) A375 cells were treated for 24 hrs with various doses of Cisplatin and then analysed for apoptosis via Annexin V-PI staining. (f) menin, γ-H2A.X, cyclinB1 and cyclinB2 protein level were detected by Western blot. ...
Cyclin T1 Antibody 20992-1-AP has been identified with WB, ELISA. 20992-1-AP detected 87 kDa band in K-562 cells with 1:200-1:1000 dilution...
"Entrez Gene: CCNB1IP1 cyclin B1 interacting protein 1". Human CCNB1IP1 genome location and CCNB1IP1 gene details page in the ... Alters Mitotic Progression through Regulation of Cyclin B Levels". Mol Cell Biol. 23 (6): 2109-22. doi:10.1128/MCB.23.6.2109- ...
"Cytoplasmic polyadenylation mediate masking and unmasking of cyclin B1 mRNA". EMBO J. 18: 2294-2303. doi:10.1093/emboj/18.8. ...
de Moor, C.H.; Richter, J.D. (1999). "Cytoplasmic polyadenylation mediate masking and unmasking of cyclin B1 mRNA". EMBO J. 18 ...
Jin P, Hardy S, Morgan DO (1998). "Nuclear Localization of Cyclin B1 Controls Mitotic Entry After DNA Damage". J. Cell Biol. ... "Specific activation of cdc25 tyrosine phosphatases by B-type cyclins: evidence for multiple roles of mitotic cyclins". Cell. 67 ... CDC25B activates the cyclin dependent kinase CDC2 by removing two phosphate groups and it is required for entry into mitosis. ...
Wolthuis (2007). "Cyclin B1-Cdk1 Activation Continues after Centrosome Separation to Control Mitotic Progression". PLOS Biology ... Many factors including cyclins, cyclin-dependent kinases (CDKs), ubiquitin ligases, inhibitors of cyclin-dependent kinases, and ... APC ubiquitinates nine-amino acid motif known as the destruction box (D box) in the NH2-terminal domain of mitotic cyclins for ... Cdc20 and Cdh1, which are the activators of APC, recruit substrates such as securin and B-type cyclins(Clb) for ubiquitination ...
2011). "Upregulation of Cyclin B1 by miRNA and its implications in cancer". Nucleic Acids Research. 40 (4): 1695-707. doi: ...
Its expression induces cyclin B1 expression, whilst knockdown sees a resultant decreased level of mouse cyclin B through the ... 2012). "Upregulation of Cyclin B1 by miRNA and its implications in cancer". Nucleic Acids Res. 40 (4): 1695-707. doi:10.1093/ ...
This enzyme enhances the cyclin B1-Cdk1-dependent mitotic phosphorylation events during mitosis. This enzyme is also essential ...
Members of this protein family regulate translation of cyclin B1 during embryonic cell divisions. Multiple transcript variants ... of Aurora-A targets cytoplasmic polyadenylation element binding protein and promotes mRNA polyadenylation of Cdk1 and cyclin B1 ...
Cyclin B1, essential in the entry into mitosis, is targeted by SCFNIPA in interphase. Phosphorylation of NIPA occurs in G2 ... Oscillating ubiquitination of nuclear cyclin B1 driven by the SCFNIPA complex contributes to the timing of mitotic entry. NIPA ... at G2/M involves cyclin B1/Cdk1". The Journal of Biological Chemistry. 282 (22): 15965-72. doi:10.1074/jbc.M610819200. PMID ...
... has been shown to interact with: Cyclin B1, HSF1, RALA, RALB, and REPS2. GRCh38: Ensembl release 89: ENSG00000017797 - ...
"Mxi1 inhibits the proliferation of U87 glioma cells through down-regulation of cyclin B1 gene expression". Br. J. Cancer. 86 (3 ...
Cyclin D1, phosphofructokinase-muscle isoform, nuclear factor of activated T-cell, Cyclin B1, Tissue Factor and tissue factor ... "Downregulation of p21-activated kinase-1 inhibits the growth of gastric cancer cells involving cyclin B1". International ... PAK1 has been shown to interact with: ARHGEF2, ARPC1B, BMX, C-Raf, CDC42, Cyclin-dependent kinase 5, DYNLL1, LIMK1, NCK1, ... and the cyclin D1 promoter". Cancer Research. 63 (20): 6802-8. PMID 14583477. Dadke D, Fryer BH, Golemis EA, Field J (December ...
1999). "Association with Cdc2 and inhibition of Cdc2/Cyclin B1 kinase activity by the p53-regulated protein Gadd45". Oncogene. ... "Association with Cdc2 and inhibition of Cdc2/Cyclin B1 kinase activity by the p53-regulated protein Gadd45". Oncogene. 18 (18 ... Vairapandi M, Balliet AG, Hoffman B, Liebermann DA (September 2002). "GADD45b and GADD45g are cdc2/cyclinB1 kinase inhibitors ...
CDK1 (also called CDC2) is considered the main mitotic kinase in mammalian cells and is activated by Cyclin B1. Aurora kinases ... Cyclin dependent kinase complexes (CDKs) are activated by mitotic cyclins, whose translation increases during mitosis. ...
Klf4 inhibits proliferation through activation of p21Cip1/Waf1, and direct suppression of cyclin D1 and cyclin B1 gene ...
It has been shown that on a molecular level, Runx associates with the cdc2 partner cyclin B1 during mitosis. The ... Furthermore, Runx2 controls the gene expression of cyclin D2, D3, and the CDK inhibitor p21(cip1) in hematopoietic cells. ...
"Cyclin B1-Cdk1 activation continues after centrosome separation to control mitotic progression". PLoS Biology. 5 (5): e123. doi ... As the amount of cyclin increases, more and more cyclin dependent kinases attach to cyclin signaling the cell further into ... At the peak of the cyclin attached to the cyclin dependent kinases this system pushes the cell out of interphase and into the M ... The control of each checkpoint is controlled by cyclin and cyclin-dependent kinases. The progression of interphase is the ...
In addition, cyclin B1- CDK activates Drp1, causing fragmentation and ensuring mitochondria are distributed to each daughter ...
During G2 phase of the cell cycle, Cdk1 and cyclin B1 makes a complex and forms maturation promoting factor (MPF). The complex ... The system cannot be stable at intermediate levels of Cyclin B1, and the transition between the two stable states is abrupt ... Exhibiting hysteresis, for different levels of Cyclin B1, the switches from low to high and high to low states vary. However, ... Additionally, positive feedback can induce bistability in Cyclin B1- by the two regulators Wee1 and Cdc25C, leading to the ...
These molecules include regulatory proteins such as Rev, MAPK/MEK1, c-Abl, Cyclin B1, MDM2/p53, IkB, MPF, and PKA. The most ...
Heikinheimo O, Lanzendorf SE, Baka SG, Gibbons WE (1995). "Cell cycle genes c-mos and cyclin-B1 are expressed in a specific ...
It is known that cyclin B1 can compensate for loss of both cyclin B2 (and vice versa in Drosophila). Cyclin B1/CDK1 activity is ... Inactive Cyclin B1/CDK1 is sequestered in the nucleus by p21, while active Cyclin B1/CDK1 complexes are sequestered in the ... In mammals, cyclin B1/CDK1 translocation to the nucleus is activated by phosphorylation of five serine sites on cyclin B1's ... translocation of cyclin B1/CDK1 to the nucleus is extremely rapid. Once in the nucleus, cyclin B1/CDK1 phosphorylates many ...
1993). "G2 delay induced by nitrogen mustard in human cells affects cyclin A/cdk2 and cyclin B1/cdc2-kinase complexes ... Absence of a consensus sequence for the p34cdc2/cyclin B kinase". J. Biol. Chem. 270 (46): 27653-60. doi:10.1074/jbc.270.46. ...
It also interacts with CRIF, which causes the inhibition of Cdc2-cyclin B1 and Cdk-cyclin E. GADD45 also works with the cyclin- ... GADD45G prevents the kinase ability of the cyclin b1/Cdk1 complex in a fashion that does not break apart the complex. It plays ... Vairapandi M, Balliet AG, Hoffman B, Liebermann DA (2002). "GADD45b and GADD45g are cdc2/cyclinB1 kinase inhibitors with a role ...
... of human Myt1 kinase induces a G2 cell cycle delay by interfering with the intracellular trafficking of Cdc2-cyclin B1 ...
Cyclin. *A (A1, A2). *B (B1, B2, B3). *D (D1, D2, D3) ... CDK4, CMM3, PSK-J3, cyclin-dependent kinase 4, cyclin dependent ... 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 ...
"Cyclin F regulates the nuclear localization of cyclin B1 through a cyclin-cyclin interaction". The EMBO Journal. 19 (6): 1378- ... Cyclin F differs from other cyclins by its ability to monitor and regulate cell cycle without the need for cyclin-dependent ... D'Angiolella V, Esencay M, Pagano M (March 2013). "A cyclin without cyclin-dependent kinases: cyclin F controls genome ... G2/mitotic-specific cyclin-F is a protein that in humans is encoded by the CCNF gene. This gene encodes a member of the cyclin ...
... consisting of cyclin B1 and the cyclin-dependent kinase Cdc2 was assessed in primary cultures of postmitotic ventricular adult ... Simultaneous ectopic expression of wild-type versions of cyclin B1 and Cdc2 was sufficient to induce MPF activity. ... to divide shortly after birth and an irreversible cell cycle arrest is evident accompanied by the downregulation of cyclin- ...
cyclin-dependent kinase B1;2 [Arabidopsis thaliana] cyclin-dependent kinase B1;2 [Arabidopsis thaliana]. gi,42569741,ref,NP_ ... cyclin-dependent kinase B1;2 [Arabidopsis thaliana]. NCBI Reference Sequence: NP_181396.2 ... Encodes a member of a plant specific family of cyclin dependent kinases. Also Known As: AT2G38620, CYCLIN-DEPEN... ...
G2/mitotic-specific cyclin-B1. Names. cyclin B1, related sequence 1. cyclin B1, related sequence 13. ... Immunity against cyclin B1 tumor antigen delays development of spontaneous cyclin B1-positive tumors in p53 (-/-) mice. Vella ... Cyclin A/B1 associated events during G2/M transition, organism-specific biosystem (from REACTOME) Cyclin A/B1 associated events ... Cyclin_N; Cyclin, N-terminal domain. pfam02984. Location:297 → 415. Cyclin_C; Cyclin, C-terminal domain. ...
"Cyclin F regulates the nuclear localization of cyclin B1 through a cyclin-cyclin interaction". EMBO J. 19 (6): 1378-88. doi: ... G2/mitotic-specific cyclin-B1 is a protein that in humans is encoded by the CCNB1 gene. Cyclin B1 is a regulatory protein ... Cyclin B1 can reside in the nucleus or the cytoplasm which can have an effect on the malignant potential of cyclin B1 when ... Once cyclin B1-Cdk1 is activated, it remains stably active for the rest of mitosis. Another mechanism by which cyclin B1-Cdk1 ...
Abcam provides specific protocols for Anti-Cyclin B1 antibody [V152] (ab72) : Flow cytometry protocols, Immunohistochemistry ...
Abcam provides specific protocols for Anti-Cyclin B1 (phospho S126) antibody (ab3488) : Western blot protocols, ...
Mouse anti-Cyclin B1, Clone: SPM619, Novus Biologicals 0.02mg; Unlabeled Life Sciences:Antibodies:Primary Antibodies:Flow ... CCNB, cyclin B1, G2/mitotic-specific cyclin B1, G2/mitotic-specific cyclin-B1. ... Cyclin B1 Monoclonal antibody specifically detects Cyclin B1 in Human, Mouse samples. It is validated for Flow Cytometry, ... It recognizes a protein of 55-62kDa, identified as cyclin B1. In mammals, cyclin B associates with inactive p34cdc2, which ...
Rabbit Polyclonal Cyclin B1 antibody for IP, ELISA, WB. Published in 1 Pubmed Reference. Order anti-Cyclin B1 antibody ... anti-Cyclin B1 antibody was diluted 1:500 to detect Cyclin B1 in human brain cerebellum tissue. Tissue was formalin fixed and ... anti-Cyclin B1 antibody was diluted 1:500 to detect Cyclin B1 in human brain cerebellum tissue. Tissue was formalin fixed and ... anti-Cyclin B1 antibody was diluted 1:500 to detect Cyclin B1 in human brain cerebellum tissue. Tissue was formalin fixed and ...
Compare and order Cyclin B1 ELISA Kits. View citations, images, detection ranges, sensitivity, prices and more. Recommended ... cyclin B1 , cyclin B4 , G2/mitotic-specific cyclin B1 , cyclin B1, related sequence 1 , cyclin B1, related sequence 13 , cyclin ... Bezeichner auf Proteinebene für Cyclin B1 G2/mitotic-specific cyclin-B1 , cyclinB , etID61116.5 , ... Cyclin B1 Antigen Profile Beschreibung des Gens The protein encoded by this gene is a regulatory protein involved in mitosis. ...
... cyclin B1) for IHC-P, WB. Anti-Cyclin B1 pAb (GTX100911) is tested in Human, Mouse samples. 100% Ab-Assurance. ... CCNB antibody, CCNB1 antibody, G2/mitotic-specific cyclin-B1 antibody, G2/mitotic-specific cyclin B1 antibody, cyclin B1 ... Cyclin B1 antibody detects Cyclin B1 protein at cytoplasm on mouse ovary by immunohistochemical analysis. Sample: Paraffin- ... Cyclin B1 antibody detects Cyclin B1 protein at cytoplasm on mouse ovary by immunohistochemical analysis. Sample: Paraffin- ...
... Manni I., Tunici P. ... This inhibition occurs at the transcriptional level and depends, at least in part, on the E-box present on the cyclin B1 ... Interestingly, the expression of cyclin B1 was inhibited to about 60% in U87.Mxi1.14 cells. ... suppressor in human glioblastomas through a molecular mechanism involving the transcriptional down-regulation of cyclin B1 gene ...
... cyclin B1) for IHC-P. Anti-Cyclin B1 mAb (GTX34616) is tested in Human, Mouse samples. 100% Ab-Assurance. ... cyclin B1 Antibody. Specificity. It recognizes a protein of 55-62kDa, identified as cyclin B1. In mammals, cyclin B associates ... cyclin B1. Background. The protein encoded by this gene is a regulatory protein involved in mitosis. The gene product complexes ... Formalin-fixed, paraffin-embedded human Tonsil stained with Cyclin B1 Monoclonal Antibody (SPM619). Top ...
Jetzt diesen anti-Cyclin B1 Antikörper bestellen. , Produkt ABIN4265761 ... Kaninchen Monoklonal Cyclin B1 Antikörper für FACS, WB. ... anti-Cyclin B1 Antikörper (CCNB1) (Alexa Fluor 488) Cyclin B1 ... Produktdetails anti-Cyclin B1 Antikörper Handhabung Anwendungsinformationen Antigendetails zurück nach oben Produktdetails anti ... Dieser Cyclin B1 Antikörper ist konjugiert mit Alexa Fluor 488 Alternativen 17 Biotin. ...
This antibody recognizes a protein of 55-62 kDa, identified as cyclin B1. In mammals, cyclin B associates with inactive p34cdc2 ... This antibody recognizes a protein of 55-62 kDa, identified as cyclin B1. ... precipitates active CDK1/cyclin B1 complexes, Optimal dilution for a specific application should be determined by user ... The inactive cyclin B-p34cdc2 complex continues to accumulate in the cytoplasm until the completion of DNA synthesis, when ...
Cyclin-dependent kinase B1-2Imported. ,p>Information which has been imported from another database using automatic procedures ... tr,A0A1J3JA08,A0A1J3JA08_NOCCA Cyclin-dependent kinase B1-2 (Fragment) OS=Noccaea caerulescens OX=107243 GN=MP_TR1527_c0_g1_i1_ ...
... Bjorck, E; Ek, Sara LU ; ... A high expression of CCNB1 (cyclin B1), CDC2, CDKN3A, CKS1B, ANP32E, and KIAA0101, but not of the proliferation-related antigen ... A high expression of CCNB1 (cyclin B1), CDC2, CDKN3A, CKS1B, ANP32E, and KIAA0101, but not of the proliferation-related antigen ... High expression of cyclin B1 predicts a favorable outcome in patients with follicular lymphoma}, url = {http://dx.doi.org/ ...
Phosphorylation of Cyclin B1 in the CRS domain (Caenorhabditis elegans) * Translocation of CRS phosphorylated Cyclin B1:Cdc2 ... CAK-mediated phosphorylation of Cyclin B1:Cdc2 complexes (Caenorhabditis elegans) * Translocation of Cyclin B1:phospho-Cdc2 to ... Myt-1 mediated phosphorylation of Cyclin B:Cdc2 complexes (Caenorhabditis elegans) * Translocation of Cyclin B1:phospho-Cdc2 ... Dephosphorylation of cytoplasmic Cyclin B1/B2:phospho-Cdc2 (Thr 14, Tyr 15) complexes by CDC25B (Caenorhabditis elegans) ...
Expression of cyclin B1 in human endometrium detected by Western blot. The relative expression of cyclin B1 in human ... Progesterone and/or Alp decreases the expression of cyclin B1 The expression of cyclin B1 was significantly decreased by the ... Cyclin B1 is the key component of the cell cycle machinery[14]. Cyclin B1 binds to Cdc2 at the beginning of G2 phase forming an ... upregulated expression of cyclin B1, cyclin D1 and cyclin E was detected in endometrial carcinomas, which indicated that ...
The Tumor Antigen Cyclin B1 Hosts Multiple CD4 T Cell Epitopes Differently Recognized by Pre-Existing Naive and Memory Cells in ... Claire Chevaleyre, Nadine Benhamouda, Emmanuel Favry, Elizabeth Fabre, Anais Mhoumadi, et al.. The Tumor Antigen Cyclin B1 ...
Levels of cyclin D1 and p27 were calculated using the ΔCT method and represented as fold changes by taking the levels of cyclin ... Gossypin as a Novel Selective Dual Inhibitor of v-raf Murine Sarcoma Viral Oncogene Homolog B1 and Cyclin-Dependent Kinase 4 ... Gossypin as a Novel Selective Dual Inhibitor of v-raf Murine Sarcoma Viral Oncogene Homolog B1 and Cyclin-Dependent Kinase 4 ... Gossypin as a Novel Selective Dual Inhibitor of v-raf Murine Sarcoma Viral Oncogene Homolog B1 and Cyclin-Dependent Kinase 4 ...
a) Antibody titers to cyclin B1 in ELISA were expressed as optical density (OD) units. The mean + 3SD of normal human sera are ... to cyclin B1 before and after absorption in nitrocellulose membrane strips blotted with purified recombinant cyclin B1 protein ... to cyclin B1 before and after absorption in nitrocellulose membrane strips blotted with purified recombinant cyclin B1 protein ... Autoantibodies to cyclin B1 were detected in 31.0% of sera from randomly selected patients with PCa versus 4.8% in sera with ...
ATP-Binding Cassette B1 Transports Seliciclib (R-Roscovitine), a Cyclin-Dependent Kinase Inhibitor. Zsuzsanna Rajnai, Dóra Méhn ... ATP-Binding Cassette B1 Transports Seliciclib (R-Roscovitine), a Cyclin-Dependent Kinase Inhibitor. Zsuzsanna Rajnai, Dóra Méhn ... ATP-Binding Cassette B1 Transports Seliciclib (R-Roscovitine), a Cyclin-Dependent Kinase Inhibitor. Zsuzsanna Rajnai, Dóra Méhn ... ATP-Binding Cassette B1 Transports Seliciclib (R-Roscovitine), a Cyclin-Dependent Kinase Inhibitor ...
CCNB1; cyclin B1; CCNB; G2/mitotic-specific cyclin-B1; OTTHUMP00000123478; OTTHUMP00000221981; OTTHUMP00000223023; G2/mitotic- ... Recombinant Human Cyclin B1, His-tagged. E. coli. Human. His. +Inquiry. CCNB1-2983M. Recombinant Mouse CCNB1 Protein. Mammalian ...
Among these, Thr-622 was specifically phosphorylated by Cdk1-cyclin B1 both in vitro and in vivo. Interestingly, compared with ... Cdk1-Cyclin B1-mediated Phosphorylation of Tumor-associated Microtubule-associated Protein/Cytoskeleton-associated Protein 2 in ... These findings suggest that Cdk1-cyclin B1-mediated phosphorylation of TMAP is important for and contributes to proper ...
... which disrupted Cyclin B1-CRM1 interactions, led to a marked nuclear accumulation of Cyclin B1. In mitosis, Cyclin B1 undergoes ... Cyclin B. Cyclin B1. Fatty Acids, Unsaturated. Guanosine Diphosphate. HeLa Cells. Humans. Intracellular Signaling Peptides and ... Activation of the Cyclin B/Cdc2 kinase complex triggers entry into mitosis in all eukaryotic cells. Cyclin B1 localization ... Control of cyclin B1 localization through regulated binding of the nuclear export factor CRM1. ...
  • Huanglian represents a class of agents that can inhibit tumor cell growth by directly suppressing the expression of a cyclin subunit that is critical for cell cycle progression. (aspetjournals.org)
  • BACKGROUND It has been reported that p53 regulates the G2-M checkpoint transition through cyclin B1, and it has been suggested that p53 plays an important role in the development and progression of various malignancies. (semanticscholar.org)
  • The role of cyclin B1 is to transition the cell from G2 to M phase but becomes unregulated in cancer cells where overexpression of cyclin B1 can lead to uncontrolled cell growth by binding to its partner Cdks. (wikipedia.org)
  • Like all cyclins, levels of cyclin B1 oscillate over the course of the cell cycle. (wikipedia.org)
  • These high levels of cyclin B1 can also be associated to the extent of tumor invasion and aggressiveness therefore concentration of cyclin B1 can be used to determine the prognosis of cancer patients. (wikipedia.org)
  • Indeed, the cyclin B1 promoter maintains an open chromatin configuration at the mitotic stage. (embopress.org)
  • Investigation of the mechanism by which methylation decreased Sp1 activity found that methylation of Sp1 increased the recruitment of Su(var) 3-9 homologue 1(Suv39H1) and histone deacetylase 1 (HDAC1) to the cyclin B1 promoter, resulting in deacetylation and methylation of histone H3 and subsequent downregulation of cyclin B1. (elsevier.com)
  • This decrease was partially blocked by concurrent treatment with the proteasome inhibitor calpain inhibitor I. Using a luciferase-based reporter assay, resveratrol did not inhibit cyclin D1 promoter activity in SW480 cells. (aacrjournals.org)
  • The objective of the current study was to clarify the role of the cell cycle regulators, cyclin B1 and p53, in patients with esophageal squamous cell carcinoma (ESCC). (semanticscholar.org)
  • This mitotic kinase complex remains active until the metaphase/anaphase transition when cyclin B is degraded. (fishersci.com)
  • 2013 ). MCC-bound APC/C is incapable of poly-ubiquitinating its metaphase substrates, securin and cyclin B1, at least in large part due to the actions of BUBR1, which occupies a substrate-recognition site on CDC20 and likely has additional inhibitory interactions with the APC/C (Lara-Gonzalez et al. (springer.com)
  • Preferential autoimmune response in prostate cancer to cyclin B1 in a panel of tumor-associated antigens. (nih.gov)
  • In conclusion, cyclin A, cyclin D1, p21 and p27 expression can be a valuable marker of poor prognosis and tumor aggressiveness in OSCC. (omicsonline.org)
  • Cyclin B1 overexpression can mimic the effects of Fzr1 loss on GV arrest and here we show that cyclin B1 knockdown in Fzr1 Δ/Δ oocytes affects the timing of meiotic resumption. (biologists.org)
  • Another mechanism by which cyclin B1-Cdk1 activity is regulated is through subcellular localization. (wikipedia.org)
  • Control of cyclin B1 localization through regulated binding of the nuclear export factor CRM1. (duke.edu)
  • Cyclin B1 can reside in the nucleus or the cytoplasm which can have an effect on the malignant potential of cyclin B1 when overexpressed in each location. (wikipedia.org)
  • The inactive cyclin B-p34cdc2 complex continues to accumulate in the cytoplasm until the completion of DNA synthesis, when Cdc25, a specific protein phosphatase, dephosphorylates aa 14Thr and 15Tyr of p34cdc2 rendering the complex active at the G2/M boundary. (fishersci.com)
  • Cyclin B1 levels were elevated ~5-fold in Fzr1 Δ/Δ oocytes, whereas securin and CDC25B, two other APC/C FZR1 substrates, were unchanged. (biologists.org)
  • Cyclins themselves have no enzymatic activity but have binding sites for some substrates and target the Cdks to specific subcellular locations. (wikipedia.org)
  • Here we show that the functional human ortholog of Greatwall protein kinase (Gwl) is the microtubule-associated serine/threonine kinase-like protein, MAST-L. This kinase promotes mitotic entry and maintenance in human cells by inhibiting protein phosphatase 2A (PP2A), a phosphatase that dephosphorylates cyclin B-Cdc2 substrates. (pnas.org)
  • This study shows that seliciclib is a high-affinity substrate of ATP-binding cassette B1 (ABCB1) because it activates the ATPase activity of the transporter with an EC 50 of 4.2 μM and shows vectorial transport in MDCKII-MDR1 cells, yielding an efflux ratio of 8. (aspetjournals.org)
  • In support of this hypothesis, we found that treatment of cells with leptomycin B, which disrupted Cyclin B1-CRM1 interactions, led to a marked nuclear accumulation of Cyclin B1. (duke.edu)
  • Here we provide evidence for cyclin B1 transcription at the mitotic stage in mammalian cells. (embopress.org)
  • Chuang, JY , Chang, WC & Hung, JJ 2011, ' Hydrogen peroxide induces Sp1 methylation and thereby suppresses cyclin B1 via recruitment of Suv39H1 and HDAC1 in cancer cells ', Free Radical Biology and Medicine , vol. 51, no. 12, pp. 2309-2318. (elsevier.com)
  • Natural killer T cells play an important role in liver regeneration, which is associated with cyclin B1 and interleukin-6. (biomedcentral.com)
  • Cyclins can be divided into four classes based on their behavior in the cell cycle of vertebrate somatic cells and yeast cells: G1 cyclins, G1/S cyclins, S cyclins, and M cyclins. (wikipedia.org)
  • Expression of cyclins detected immunocytochemically in individual cells in relation to cellular DNA content (cell cycle phase), or in relation to initiation and termination of DNA replication during S-phase, can be measured by flow cytometry . (wikipedia.org)
  • In eukaryotic cells, the mitotic state is maintained by the mitotic kinase cyclin B-Cdc2. (pnas.org)
  • Differential cell cycle modulation by this CG led to a G2/M arrest, cyclin B1 and p53 downregulation in A549, but not in U937 cells. (frontiersin.org)
  • In SW480 cells, cyclin A, cyclin B1, and β-catenin expression levels were decreased within 24 h. (aacrjournals.org)
  • For example, cyclin D recruits transcriptional corepressors to endoderm genes and coactivators to neuroectoderm genes during the differentiation of human embryonic stem cells ( 8 ). (asm.org)
  • Results provide evidence that cdc2/cyclin B1 kinase activation was synchronous with the initial appearance of cytoskeletal lesions in mouse with Niemann-Pick disease type C. (nih.gov)
  • Title: Aberrant activation of Cdc2/cyclin B1 is involved in initiation of cytoskeletal pathology in murine Niemann-Pick disease type C. (nih.gov)
  • Its activation is well-regulated, and positive feedback loops ensure that once the cyclin B1-Cdk1 complex is activated, it is not deactivated. (wikipedia.org)
  • This activation was transitory since cyclin B1 levels recovered between Ca2+ spikes. (ncl.ac.uk)
  • Historically, mitotic entry and exit was thought to be the direct consequence of cyclin B-Cdc2 activation and inactivation, respectively ( 1 ). (pnas.org)
  • In multivariate analysis, cyclin B1 was not an independent prognostic factor (p=0.067). (garvan.org.au)
  • Cyclin B1 but not cyclin A shows some promise as a potential prognostic marker in NSCLC. (garvan.org.au)