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.Diterpenes: Twenty-carbon compounds derived from MEVALONIC ACID or deoxyxylulose phosphate.DNA Polymerase II: A DNA-dependent DNA polymerase characterized in E. coli and other lower organisms. It may be present in higher organisms and has an intrinsic molecular activity only 5% of that of DNA Polymerase I. This polymerase has 3'-5' exonuclease activity, is effective only on duplex DNA with gaps or single-strand ends of less than 100 nucleotides as template, and is inhibited by sulfhydryl reagents. EC 2.7.7.7.DNA Replication: The process by which a DNA molecule is duplicated.DNA-Directed DNA Polymerase: DNA-dependent DNA polymerases found in bacteria, animal and plant cells. During the replication process, these enzymes catalyze the addition of deoxyribonucleotide residues to the end of a DNA strand in the presence of DNA as template-primer. They also possess exonuclease activity and therefore function in DNA repair.Chromosome Fragile Sites: Specific loci that show up during KARYOTYPING as a gap (an uncondensed stretch in closer views) on a CHROMATID arm after culturing cells under specific conditions. These sites are associated with an increase in CHROMOSOME FRAGILITY. They are classified as common or rare, and by the specific culture conditions under which they develop. Fragile site loci are named by the letters "FRA" followed by a designation for the specific chromosome, and a letter which refers to which fragile site of that chromosome (e.g. FRAXA refers to fragile site A on the X chromosome. It is a rare, folic acid-sensitive fragile site associated with FRAGILE X SYNDROME.)Chromosome Fragility: Susceptibility of chromosomes to breakage leading to translocation; CHROMOSOME INVERSION; SEQUENCE DELETION; or other CHROMOSOME BREAKAGE related aberrations.Mimosine: 3-Hydroxy-4-oxo-1(4H)-pyridinealanine. An antineoplastic alanine-substituted pyridine derivative isolated from Leucena glauca.Phosphonoacetic Acid: A simple organophosphorus compound that inhibits DNA polymerase, especially in viruses and is used as an antiviral agent.Hydroxyurea: An antineoplastic agent that inhibits DNA synthesis through the inhibition of ribonucleoside diphosphate reductase.DNA Polymerase I: A DNA-dependent DNA polymerase characterized in prokaryotes and may be present in higher organisms. It has both 3'-5' and 5'-3' exonuclease activity, but cannot use native double-stranded DNA as template-primer. It is not inhibited by sulfhydryl reagents and is active in both DNA synthesis and repair. EC 2.7.7.7.Deoxyribonucleotides: A purine or pyrimidine base bonded to a DEOXYRIBOSE containing a bond to a phosphate group.Nucleic Acid Synthesis Inhibitors: Compounds that inhibit cell production of DNA or RNA.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.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.Desmosterol: An intermediate in the synthesis of cholesterol.Deoxycytosine Nucleotides: Cytosine nucleotides which contain deoxyribose as the sugar moiety.DNA Polymerase III: A DNA-dependent DNA polymerase characterized in E. coli and other lower organisms but may be present in higher organisms. Use also for a more complex form of DNA polymerase III designated as DNA polymerase III* or pol III* which is 15 times more active biologically than DNA polymerase I in the synthesis of DNA. This polymerase has both 3'-5' and 5'-3' exonuclease activities, is inhibited by sulfhydryl reagents, and has the same template-primer dependence as pol II. EC 2.7.7.7.DNA: A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).Kinetics: The rate dynamics in chemical or physical systems.Cell Line: Established cell cultures that have the potential to propagate indefinitely.Formazans: Colored azo compounds formed by the reduction of tetrazolium salts. Employing this reaction, oxidoreductase activity can be determined quantitatively in tissue sections by allowing the enzymes to act on their specific substrates in the presence of tetrazolium salts.Deoxyguanine Nucleotides: Guanine nucleotides which contain deoxyribose as the sugar moiety.Parvoviridae: A family of very small DNA viruses containing a single molecule of single-stranded DNA and consisting of two subfamilies: PARVOVIRINAE and DENSOVIRINAE. They infect both vertebrates and invertebrates.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)DNA, Viral: Deoxyribonucleic acid that makes up the genetic material of viruses.Antiviral Agents: Agents used in the prophylaxis or therapy of VIRUS DISEASES. Some of the ways they may act include preventing viral replication by inhibiting viral DNA polymerase; binding to specific cell-surface receptors and inhibiting viral penetration or uncoating; inhibiting viral protein synthesis; or blocking late stages of virus assembly.Simian virus 40: A species of POLYOMAVIRUS originally isolated from Rhesus monkey kidney tissue. It produces malignancy in human and newborn hamster kidney cell cultures.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.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.Saccharomyces cerevisiae: A species of the genus SACCHAROMYCES, family Saccharomycetaceae, order Saccharomycetales, known as "baker's" or "brewer's" yeast. The dried form is used as a dietary supplement.Genetic Complementation Test: A test used to determine whether or not complementation (compensation in the form of dominance) will occur in a cell with a given mutant phenotype when another mutant genome, encoding the same mutant phenotype, is introduced into that cell.Saccharomyces cerevisiae Proteins: Proteins obtained from the species SACCHAROMYCES CEREVISIAE. The function of specific proteins from this organism are the subject of intense scientific interest and have been used to derive basic understanding of the functioning similar proteins in higher eukaryotes.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.Mutation: Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Simplexvirus: A genus of the family HERPESVIRIDAE, subfamily ALPHAHERPESVIRINAE, consisting of herpes simplex-like viruses. The type species is HERPESVIRUS 1, HUMAN.Herpes Simplex: A group of acute infections caused by herpes simplex virus type 1 or type 2 that is characterized by the development of one or more small fluid-filled vesicles with a raised erythematous base on the skin or mucous membrane. It occurs as a primary infection or recurs due to a reactivation of a latent infection. (Dorland, 27th ed.)Herpesvirus 1, Human: The type species of SIMPLEXVIRUS causing most forms of non-genital herpes simplex in humans. Primary infection occurs mainly in infants and young children and then the virus becomes latent in the dorsal root ganglion. It then is periodically reactivated throughout life causing mostly benign conditions.Rhombencephalon: The posterior of the three primitive cerebral vesicles of an embryonic brain. It consists of myelencephalon, metencephalon, and isthmus rhombencephali from which develop the major BRAIN STEM components, such as MEDULLA OBLONGATA from the myelencephalon, CEREBELLUM and PONS from the metencephalon, with the expanded cavity forming the FOURTH VENTRICLE.Basic Helix-Loop-Helix Transcription Factors: A family of DNA-binding transcription factors that contain a basic HELIX-LOOP-HELIX MOTIF.Neurogenesis: Formation of NEURONS which involves the differentiation and division of STEM CELLS in which one or both of the daughter cells become neurons.Transcription Factors: Endogenous substances, usually proteins, which are effective in the initiation, stimulation, or termination of the genetic transcription process.Mesencephalon: The middle of the three primitive cerebral vesicles of the embryonic brain. Without further subdivision, midbrain develops into a short, constricted portion connecting the PONS and the DIENCEPHALON. Midbrain contains two major parts, the dorsal TECTUM MESENCEPHALI and the ventral TEGMENTUM MESENCEPHALI, housing components of auditory, visual, and other sensorimoter systems.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.Helix-Loop-Helix Motifs: Recurring supersecondary structures characterized by 20 amino acids folding into two alpha helices connected by a non-helical "loop" segment. They are found in many sequence-specific DNA-BINDING PROTEINS and in CALCIUM-BINDING PROTEINS.Prussia: Former state in north central Germany. Formally abolished March 1, 1947. Kingdom established 1701.Encyclopedias as Topic: Works containing information articles on subjects in every field of knowledge, usually arranged in alphabetical order, or a similar work limited to a special field or subject. (From The ALA Glossary of Library and Information Science, 1983)Chemistry, Organic: The study of the structure, preparation, properties, and reactions of carbon compounds. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Imino Sugars: Sugars in which the OXYGEN is replaced by a NITROGEN atom. This substitution prevents normal METABOLISM resulting in inhibition of GLYCOSIDASES and GLYCOSYLTRANSFERASES.Carboxylic Acids: Organic compounds containing the carboxy group (-COOH). This group of compounds includes amino acids and fatty acids. Carboxylic acids can be saturated, unsaturated, or aromatic.Cycloaddition Reaction: Synthetic organic reactions that use reactions between unsaturated molecules to form cyclical products.Gene Rearrangement: The ordered rearrangement of gene regions by DNA recombination such as that which occurs normally during development.

Involvement of p21 in the PKC-induced regulation of the G2/M cell cycle transition. (1/594)

Activation of protein kinase C (PKC) inhibits cell cycle progression at the G1/S and G2/M transitions. We found that phorbol 12-myristate 13-acetate (PMA) induced upregulation of p21, not only in MCF-7 cells arrested in the G1 phase as previously shown, but also in cells delayed in the G2 phase. This increase in p21 in cells accumulated in the G1 and G2/M phases of the cell cycle after PMA treatment was inhibited by the PKC inhibitor GF109203X. This indicates that PKC activity is required for PMA-induced p21 upregulation and cell cycle arrest in the G1 and G2/M phases of the cell cycle. To further assess the role of p21 in the PKC-induced G2/M cell cycle arrest independently of its G1 arrest, we used aphidicolin-synchronised MCF-7 cells. Our results show that, in parallel with the inhibition of cdc2 activity, PMA addition enhanced the associations between p21 and either cyclin B or cdc2. Furthermore, we found that after PMA treatment p21 was able to associate with the active Tyr-15 dephosphorylated form of cdc2, but this complex was devoid of kinase activity indicating that p21 may play a role in inhibition of cdc2 induced by PMA. Taken together, these observations provide evidence that p21 is involved in integrating the PKC signaling pathway to the cell cycle machinery at the G2/M cell cycle checkpoint.  (+info)

Cell cycle-dependent nuclear accumulation of the p94fer tyrosine kinase is regulated by its NH2 terminus and is affected by kinase domain integrity and ATP binding. (2/594)

p94fer and p51ferT are two tyrosine kinases that are encoded by differentially spliced transcripts of the FER locus in the mouse. The two tyrosine kinases share identical SH2 and kinase domains but differ in their NH2-terminal amino acid sequence. Unlike p94fer, the presence of which has been demonstrated in most mammalian cell lines analyzed, the expression of p51ferT is restricted to meiotic cells. Here, we show that the two related tyrosine kinases also differ in their subcellular localization profiles. Although p51ferT accumulates constitutively in the cell nucleus, p94fer is cytoplasmic in quiescent cells and enters the nucleus concomitantly with the onset of S phase. The nuclear translocation of the FER proteins is driven by a nuclear localization signal (NLS), which is located within the kinase domain of these enzymes. The functioning of that NLS depends on the integrity of the kinase domain but was not affected by inactivation of the kinase activity. The NH2 terminus of p94fer dictated the cell cycle-dependent functioning of the NLS of FER kinase. This process was governed by coiled-coil forming sequences that are present in the NH2 terminus of the kinase. The regulatory effect of the p94fer NH2-terminal sequences was not affected by kinase activity but was perturbed by mutations in the kinase domain ATP binding site. Ectopic expression of the constitutively nuclear p51ferT in CHO cells interfered with S-phase progression in these cells. This was not seen in p94fer-overexpressing cells. The FER tyrosine kinases seem, thus, to be regulated by novel mechanisms that direct their different subcellular distribution profiles and may, consequently, control their cellular functioning.  (+info)

Nucleo-cytoplasmic interactions that control nuclear envelope breakdown and entry into mitosis in the sea urchin zygote. (3/594)

In sea urchin zygotes and mammalian cells nuclear envelope breakdown (NEB) is not driven simply by a rise in cytoplasmic cyclin dependent kinase 1-cyclin B (Cdk1-B) activity; the checkpoint monitoring DNA synthesis can prevent NEB in the face of mitotic levels of Cdk1-B. Using sea urchin zygotes we investigated whether this checkpoint prevents NEB by restricting import of regulatory proteins into the nucleus. We find that cyclin B1-GFP accumulates in nuclei that cannot complete DNA synthesis and do not break down. Thus, this checkpoint limits NEB downstream of both the cytoplasmic activation and nuclear accumulation of Cdk1-B1. In separate experiments we fertilize sea urchin eggs with sperm whose DNA has been covalently cross-linked to inhibit replication. When the pronuclei fuse, the resulting zygote nucleus does not break down for >180 minutes (equivalent to three cell cycles), even though Cdk1-B activity rises to greater than mitotic levels. If pronuclear fusion is prevented, then the female pronucleus breaks down at the normal time (average 68 minutes) and the male pronucleus with cross-linked DNA breaks down 16 minutes later. This male pronucleus has a functional checkpoint because it does not break down for >120 minutes if the female pronucleus is removed just prior to NEB. These results reveal the existence of an activity released by the female pronucleus upon its breakdown, that overrides the checkpoint in the male pronucleus and induces NEB. Microinjecting wheat germ agglutinin into binucleate zygotes reveals that this activity involves molecules that must be actively translocated into the male pronucleus.  (+info)

The Drosophila ATM homologue Mei-41 has an essential checkpoint function at the midblastula transition. (4/594)

BACKGROUND: Drosophila embryogenesis is initiated by 13 rapid syncytial mitotic divisions that do not require zygotic gene activity. This maternally directed cleavage phase of development terminates at the midblastula transition (MBT), at which point the cell cycle slows dramatically, membranes surround the cortical nuclei to form a cellular blastoderm, and zygotic gene expression is first required. RESULTS: We show that embryos lacking Mei-41, a Drosophila homologue of the ATM tumor suppressor, proceed through unusually short syncytial mitoses, fail to terminate syncytial division following mitosis 13, and degenerate without forming cells. A similar cleavage-stage arrest is produced by mutations in grapes, which encodes a homologue of the Checkpoint-1 kinase. We present biochemical, cytological and genetic data indicating that Mei-41 and Grapes are components of a conserved DNA-replication/damage checkpoint pathway that triggers inhibitory phosphorylation of the Cdc2 kinase and mediates resistance to replication inhibitors and DNA-damaging agents. This pathway is nonessential during postembryonic development, but it is required to terminate the cleavage stage at the MBT. Cyclins are required for Cdc2 kinase activity, and mutations in cyclin A and cyclin B bypass the requirement for mei-41 at the MBT. These mutations do not restore wild-type syncytial cell-cycle timing or the embryonic replication checkpoint, however, suggesting that Mei-41-mediated inhibition of Cdc2 has an additional essential function at the MBT. CONCLUSIONS: The Drosophila DNA-replication/damage checkpoint pathway can be activated by externally triggered DNA damage or replication defects throughout the life cycle, and under laboratory conditions this inducible function is nonessential. During early embryogenesis, however, this pathway is activated by developmental cues and is required for the transition from maternal to zygotic control of development at the MBT.  (+info)

Modulation of drug resistance mediated by loss of mismatch repair by the DNA polymerase inhibitor aphidicolin. (5/594)

Loss of expression of mismatch repair (MMR) proteins leads to resistance of tumor cells to a variety of DNA-damaging agents, including bifunctional alkylating and monofunctional methylating agents such as cis-diaminedichloroplatinum II (CDDP) and N'-methyl-N-nitrosourea (MNU). It has been suggested that coupling to cell death does not occur in the absence of MMR, but instead, DNA lesions are bypassed during replication, giving a drug-tolerant phenotype. In the present study, we have used aphidicolin (Ap), an inhibitor of DNA polymerases, to study the role of replicative bypass in drug resistance mediated by loss of MMR. We have examined the survival of matched ovarian carcinoma cell lines with known MMR status after sequential treatment with CDDP or MNU and Ap. We show that Ap increases the sensitivity of MMR-deficient cell lines to CDDP and MNU to a greater extent than their MMR-proficient counterparts. Furthermore, loss of MMR correlates with loss of CDDP-induced G2 arrest, but this is partially restored after Ap treatment. These data support Ap sensitizing drug-resistant cancer cells that have lost MMR to CDDP and MNU and suggest that the potential use of Ap as a modulator of drug resistance should be targeted to MMR-defective tumors.  (+info)

Developmental activation of the capability to undergo checkpoint-induced apoptosis in the early zebrafish embryo. (6/594)

In this study, we demonstrate the developmental activation, in the zebrafish embryo, of a surveillance mechanism which triggers apoptosis to remove damaged cells. We determine the time course of activation of this mechanism by exposing embryos to camptothecin, an agent which specifically inhibits topoisomerase I within the DNA replication complex and which, as a consequence of this inhibition, also produces strand breaks in the genomic DNA. In response to an early (pre-gastrula) treatment with camptothecin, apoptosis is induced at a time corresponding approximately to mid-gastrula stage in controls. This apoptotic response to a block of DNA replication can also be induced by early (pre-MBT) treatment with the DNA synthesis inhibitors hydroxyurea and aphidicolin. After camptothecin treatment, a high proportion of cells in two of the embryo's three mitotic domains (the enveloping and deep cell layers), but not in the remaining domain (the yolk syncytial layer), undergoes apoptosis in a cell-autonomous fashion. The first step in this response is an arrest of the proliferation of all deep- and enveloping-layer cells. These cells continue to increase in nuclear volume and to synthesize DNA. Eventually they become apoptotic, by a stereotypic pathway which involves cell membrane blebbing, "margination" and fragmentation of nuclei, and cleavage of the genomic DNA to produce a nucleosomal ladder. Fragmentation of nuclei can be blocked by the caspase-1,4,5 inhibitor Ac-YVAD-CHO, but not by the caspase-2,3,7[, 1] inhibitor Ac-DEVD-CHO. This suggests a functional requirement for caspase-4 or caspase-5 in the apoptotic response to camptothecin. Recently, Xenopus has been shown to display a developmental activation of the capability for stress- or damaged-induced apoptosis at early gastrula stage. En masse, our experiments suggest that the apoptotic responses in zebrafish and Xenopus are fundamentally similar. Thus, as for mammals, embryos of the lower vertebrates exhibit the activation of surveillance mechanisms, early in development, to produce the selective apoptosis of damaged cells.  (+info)

Cell-cycle perturbation in Sf9 cells infected with Autographa californica nucleopolyhedrovirus. (7/594)

Flow cytometry analysis of the cell-cycle progression was performed in Sf9 cells infected with Autographa californica nucleopolyhedrovirus (AcNPV) in the cultures partially synchronized by aphidicolin exposure and deprivation. Cells infected with AcNPV during the G1 phase progressed and were arrested in the S phase in the 4 h following the infection, whereas cells infected during the S phase did not progress past the S phase. Cells infected during the G2/M phase remained in the G2/M phase without mitosis during a period of 10 h. Such cell-cycle arrest was also observed in the cells infected with ts8, a temperature-sensitive mutant of AcNPV that is defective in both genomic DNA synthesis and late gene expression. Cells with >4 N DNA content accumulated in the cultures infected with wild-type AcNPV, whereas no such cells appeared in the cultures infected with ts8, suggesting that viral origin of the DNA overaccumulated in the cells with >4 N DNA content. This was confirmed by the slot blot hybridization experiments, which showed that viral DNA, but not cellular DNA, increased strikingly in Sf9 cells during the infection with AcNPV. These results indicate that AcNPV targets at least two different checkpoints to prevent normal cell-cycle progression of Sf9 cells and that neither viral DNA replication nor expression of viral late genes is a necessary prerequisite for such AcNPV-induced cell-cycle arrest. It is suggested that the cell-cycle arrest in AcNPV-infected Sf9 cells is an event triggered early in infection by specific interaction of viral gene products with cellular components that regulate cell-cycle progression.  (+info)

Antisense oligonucleotide complementary to the BamHI-H gene family of Marek's disease virus induced growth arrest of MDCC-MSB1 cells in the S-phase. (8/594)

DNA synthesis was effectively inhibited by antisense oligonucleotide A1 complementary to the BamHI-H gene family in Marek's disease virus (MDV)-derived lymphoblastoid MDCC-MSB1 cells. When a cell cycle distribution of a total cell population was analyzed by flow cytometry, the proportion of S-phase cells increased in the cell populations by treatment with oligonucleotide A1. Approximately 60-70% of the cells appeared in the S phase for 24 and 36 hr of incubation in the presence of oligonucleotide A1 (20-30% in the untreated control cells). The inhibition of cell cycle progression by treatment with oligonucleotide A1 was reversible. When the cells were treated with 5 microM aphidicolin for 12 hr, a similar pattern of cell cycle distribution was observed to that obtained after treatment with oligonucleotide A1. Aphidicolin is an inhibitor of cellular DNA polymerase alpha, and it halts progression of the cell cycle at the G1/S border or early S phase. When the cells were treated with aphidicolin for 12 hr and subsequently incubated with oligonucleotide A1, no significant difference was observed in the cycle phase distribution of cells in the presence and absence of oligonucleotide A1. In contrast, when the cells were treated with oligonucleotide A1 for 12 hr and subsequently incubated with aphidicolin, the cell cycle did not progress from the G1/S border or early S phase to the next phase.  (+info)

Seki, S; Oda, T; and Ohashi, M, "Differential effects of aphidicolin on replicative dna synthesis and unscheduled dna synthesis in permeable mouse sarcoma cells." (1980). Subject Strain Bibliography 1980. 284 ...
Iliakis, G and Nusse, M, "Aphidicolin promotes repair of potentially lethal damage in irradiated mammalian cell synchronized in s-phase." (1982). Subject Strain Bibliography 1982. 2980 ...
Please provide some assistance generating ideas for the following questions: - What is a successful lesson framework composed of? How would this framework vary between two different content areas? - Why is it important to.
Summary Aphidicolin, a tetracyclic diterpenoid which inhibits the DNA polymerase-α activities of many eukaryotic cells, inhibited herpes simplex virus growth and DNA synthesis in infected cultures and the activity of the virus DNA polymerase in vitro. A wide range of stable aphidicolin sensitivities was represented amongst a collection of virus strains with no prior exposure to this drug, but viruses with polymerase mutations selected for resistance to phosphonoacetic acid (PAA) or to acycloguanosine typically showed increased sensitivity to aphidicolin. Of 16 unrelated PAA-resistant variants, 7 were hypersensitive to aphidicolin. A number of mutants with temperature-sensitive (ts) lesions in the polymerase gene also showed increased aphidicolin sensitivity (e.g. HSV-1[mP17]tsH) or aphidicolin hypersensitivity (e.g. HSV-1[KOS]tsD9, tsC4). Resistance or hypersensitivity of virus growth and DNA synthesis in vivo were correlated with resistance or hypersensitivity of virus DNA polymerase reactions in
DNA synthesis in vitro in Brij-treated Saccharomyces cerevisiae requires the product of the CDC8 gene (Hereford, L. M. & Hartwell, L. H. (1971) Nature (London) New Biol. 234, 171-172). Extracts of wild-type A364a yeast restore DNA synthesis in Brij-treated cdc8, a mutant containing a thermolabile cdc8 gene product. This constitutes a complementation assay by which the cdc8 gene product can be monitored during purification. A heat-stable protein responsible for this complementation has been partially purified from both wild-type A364a cells and from a cdc8 temperature-sensitive mutant. The complementation activity from the mutant is thermolabile when compared to the wild-type activity, indicating that CDC8 is the structural gene for the protein. ...
Employing a novel strategy, we have virtually screened a large library of compounds to identify novel inhibitors of the reverse transcriptase (RT) of HIV-1. Fifty-six top scored compounds were tested in vitro, and two of them inhibited efficiently the DNA polymerase activity of RT. The most effective compound, N-{2
Active against HSV-1 HSV-2 (herpes simplex virus), EBV (ebstein barr virus), CMV (cytomegalo virus), HHV-6 (herpes human virus) & VZV (varicella zoster virus ...
DNA replication is a highly demanding process regarding the energy and material supply and must be precisely regulated, involving multiple cellular feedbacks. The slowing down or stalling of DNA synthesis and/or replication forks is referred to as replication stress (RS). Owing to the complexity and requirements of replication, a plethora of factors may interfere and challenge the genome stability, cell survival or affect the whole organism. This review outlines chemical compounds that are known inducers of RS and commonly used in laboratory research. These compounds act on replication by direct interaction with DNA causing DNA crosslinks and bulky lesions (cisplatin), chemical interference with the metabolism of deoxyribonucleotide triphosphates (hydroxyurea), direct inhibition of the activity of replicative DNA polymerases (aphidicolin) and interference with enzymes dealing with topological DNA stress (camptothecin, etoposide). As a variety of mechanisms can induce RS, the responses of mammalian
Complete information for FRA6G gene (Uncategorized), Fragile Site, Aphidicolin Type, Common, Fra(6)(Q15), including: function, proteins, disorders, pathways, orthologs, and expression. GeneCards - The Human Gene Compendium
InvivoGen provides a collection of inhibitors for different pathways: Signal Transduction Inhibitors, Protein Kinase inhibitors, Epigenetic Inhibitors, Heat Shock Protein Inhibitors, DNA Synthesis Inhibitors
TY - JOUR. T1 - Chromosomal aberrations and common fragile sites in neuroblastoma patients. AU - Vernole, P.. AU - Tedeschi, B.. AU - Pianca, C.. AU - Nicoletti, B.. AU - Riccardi, R.. AU - Melino, G.. PY - 1990. Y1 - 1990. N2 - We analyzed cytogenetically blood cells and bone marrow cells from 20 neuroblastoma patients. Chromosome common fragile sites were induced by aphidicolin in normal peripheral blood lymphocytes. All neuroblastoma patients showed a higher increase of aberrations after aphidicolin treatment as compared to that found in normal controls. In some cases it was possible to correlate the increase of the expression of a specific fragile site, 1p32, with deletions in the same area in bone marrow cells.. AB - We analyzed cytogenetically blood cells and bone marrow cells from 20 neuroblastoma patients. Chromosome common fragile sites were induced by aphidicolin in normal peripheral blood lymphocytes. All neuroblastoma patients showed a higher increase of aberrations after aphidicolin ...
... ,High Molecular Weight DNA Markers are suitable for sizing linear double-stranded DNA from 9 to 48 kb on low-percentage agarose gels. The 13 bands consist of 8.3- to 48.5-kb fragments generated from restriction endonuclease digests of Lambda DNA (cIind1ts857 Sam7). Ethidium bromide staining causes t,biological,biology supply,biology supplies,biology product
BioMed Research International is a peer-reviewed, Open Access journal that publishes original research articles, review articles, and clinical studies covering a wide range of subjects in life sciences and medicine. The journal is divided into 55 subject areas.
Discussion Enzymatically active DNA-PK is a central component of the cellular response to replication fork inhibition [6]. For instance, cells depleted of endogenous DNA-PKcs or expressing an enzymatically deficient kinase mutant are unable to efficiently restart stalled replication forks and show reduced clonogenic survival when treated with hydroxyurea [7]. With the notable exception of RPA32 [8], as well as of auto-phosphorylation [7], few relevant DNA-PK substrates have however been identified in response to replication stress. In this article we demonstrate that hSSB1 S134 phosphorylation is required for clonogenic survival of cells treated with the replication stress compounds hydroxyurea, aphidicolin and camptothecin, as well as establish that phosphorylation is primarily a result of DNA-PK activity. As a small decrease in hSSB1 S134 phosphorylation was also observed following the inhibition of ATM and ATR, we cannot however exclude that these kinases may also contribute a small amount to ...
V-58 is a novel inhibitor of Mtb replication within macrophages and stimulate cAMP production in Mtb, rapidly and directly activating Mtb AC Rv1625c to produce high levels of cAMP regardless of the bacterial environment or growth medium.
Chronic inflammation refers to a response by your immune system that sticks around long after an infection, injury, or exposure to a toxin. Well look at common symptoms, its role in various diseases, and the kinds of treatments that are available, from medications to anti-inflammatory diets.
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Excess Hsl7 overrides the DNA replication checkpoint. (A) Xenopus Hsl7 or β-globin mRNA was incubated in cycling extracts in the presence of aphidicolin (200
Thymidine, a pyrimidine deoxynucleoside, is a DNA synthesis inhibitor that can arrest cell at G1/S boundary, prior to DNA replication. - Mechanism of Action & Protocol.
Im wondering if the Hirt high molecular weight DNA prep has been replaced by a simpler or kit like method. I have to isolate a viral DNA from some infected tissue culture cells and would like to make it as painless as possible. Thanks for your help. Mary ...
Genomes and Genes, Locale, Publications, Species, Research Topics, Scientific Experts about Experts and Doctors on dna replication in United States
Guanazole and aphidicolin were chosen as candidates in the search for a selective, non-genotoxic inhibitor of DNA replication which could be used instead of hydroxyurea to measure DNA repair synthesis in rat hepatocyte primary cultures by liquid scintillation counting. The genotoxicity of these 3 chemicals was studied using the Salmonella/liver homogenate assay and the autoradiographic UDS test in hepatocytes. Hydroxyurea was positive in both of these assays. Guanazole and aphidicolin did not induce DNA repair in hepatocytes. Aphidicolin was not mutagenic for Salmonella typhimurium, whereas guanazole increased the revertant numbers of strain TA102 slightly. The incorporation of [3H]thymidine was measured by liquid scintillation to determine DNA repair induced by 2-acetylaminofluorene (2-AAF), aflatoxin B1, benzo[a]pyrene, cyclophosphamide, H2O2, 6-hydroxydopamine, N-methyl-N-nitro-N-nitrosoguanidine (MNNG), methylnitrosourea (MNU), 4-nitroquinoline-N-oxide and UV irradiation in the presence of ...
We are not concerned about mixed samples, because there is no preferential amplification with REPLI-g WGA. A small level of contamination from a secondary source cannot become a major component of the amplified material ...
The global herpes simplex therapeutics market was worth approximately $2.9 billion in 2009. In 2001 the market was valued at approximately $1 billion and it grew at an approximate Compound Annual Growth Rate (CAGR) of 13.9% from 2001 to 2009. The global herpes simplex therapeutics market is expected to reach $7.3 billion by 2017, after growing at a CAGR of 12.3% from 2009. The primary factor contributing to the increase in revenues over the forecast period is the increase in disease incidence. Presently, the therapeutic regimen for herpes simplex is dominated by a range of DNA polymerase inhibitors which include Zovirax, Famvir, Valtrex, Denavir and OTC (Over-the-Counter) products such as Abreva and Aviralex. This market is a significantly genericized market, with many brands across the seven geographies covered in this report. Tablet prices range between $1 and $3 depending on the brand. The average annual cost of therapy for herpes simplex therapeutics ranges between $725 and $2,050 based on ...
Pohjoismäki, J. L. O., Holmes, J. B., Wood, S. R., Yang, M. Y., Yasukawa, T., Reyes, A., Bailey, L. J., Cluett, T. J., Goffart, S., Willcox, S., Rigby, R. E., Jackson, A. P., Spelbrink, J. N., Griffith, J. D., Crouch, R. J., Jacobs, H. T., Holt, I. J., Mammalian mitochondrial DNA replication intermediates are essentially duplex but contain extensive tracts of RNA/DNA hybrid, J. Mol. Biol., 397, 1144-1155, 2010.04 ...
Fludarabine (NSC 118218) is a DNA synthesis inhibitor, which also inhibits phosphorylation of STAT1. Fludarabine, a pro-drug, is converted metabolically by dephosphorylation to the antimetabolite, F-ara-A. - Mechanism of Action & Protocol.
Our working hypothesis focuses on the convergence of prosurvival, angiogenesis and motility signals at common pathways in the local tumor microenvironment for t...
Roylco. 15 real X-rays reveal a detailed look at common breaks. Use on a light table, hold up to a window, or place on white paper. Includes idea guide/fact sheet, which gives …
There are no specific protocols for Recombinant Human DNA polymerase alpha protein (ab114839). Please download our general protocols booklet
TY - JOUR. T1 - Activation of deoxycytidine kinase by inhibition of DNA synthesis in human lymphocytes. AU - Csapó, Z.. AU - Sasvári, M.. AU - Spasokoukotskaja, T.. AU - Talianidis, Iannis. AU - Eriksson, Staffan. AU - Staub, M.. PY - 2001/1/15. Y1 - 2001/1/15. N2 - Deoxycytidine kinase (dCK, EC.2.7.1.74) is a key enzyme in the intracellular metabolism of 2-chlorodeoxyadenosine, 1β-D-arabinofuranosylcytosine, difluorodeoxycytidine, and other drugs used in chemotherapy of different leukaemias and solid tumours. Recently, stimulation of dCK activity was shown by these analogues and by other genotoxic agents such as etoposide and NaF, all of which cause severe inhibition of DNA synthesis in cell cultures. Here we describe that direct inhibition of DNA polymerases by aphidicolin stimulated dCK activity in normal lymphocytes and acute myeloid leukaemic cells, as well as in HL 60 promyelocytic cell cultures. Increased dCK activity was not due to new protein synthesis under our conditions, as ...
Analysis of Extracted DNA Samples Samples of DNA were quantitatively assayed using spectrophotometery by measuring absorbance at 260 nm (A260), 280 nm (A280), and 230 nm (A230) to determine concentration of ds DNA, and to measure A260 to A280 ratio (optimal ratio is equal to 1.8 or more and less than 2) and A260 to A230 ratio (optimal ratio is greater than 2.2). A280 is an estimate of concentration of non-DNA components. such as proteins, whereas A230 is measured to estimate concentration of other components such as detergents, peptides, carbohydrates, Inhibitors,research,lifescience,medical phenol and chloroform. Some randomly selected samples were assayed quantitatively by running on a 2% agarose gel electrophoresis, Inhibitors,research,lifescience,medical allowing the molecular weight of the DNA to be estimated. The electrophoresis resulted in a thick smear of DNA fragments with variable size ranging from very high molecular weight DNA to those about 100 bp in size (figure 1). Moreover, some ...
THERE GOES THE NEIGHBORHOODS Monday morning came around too soon. We both groaned at six when it was time to get up, eat at commons, and head out for our eight oclock class. No one ever adequately explains why all freshman year classes start so early. All the studies agree that teenagers are mindless zombies …
Have a look at common early signs of Parkinson disease that you need to look for. When dopamine levels in the brain decrease and when the neurons die, Parkinson
Not all available origins of replication fire during a normal S-phase. But when replication is perturbed, otherwise dormant origins go to work, Woodward et al. show on page 673.. Cells initially respond to slowed replication by turning on the ATR-dependent checkpoint, which prevents other origins from firing and thus getting into trouble too. But if the cell decides it is time to recover from that checkpoint, the mechanism discovered by Woodward et al. may ensure that there are enough origins to get the job done.. The excess supply of origins arises from an excess of sites that have the minichromosome maintenance protein complexes, Mcm2-7. These complexes are loaded onto chromatin before S-phase and are required to license replication origins for use. However, the number of complexes loaded is much higher than the number normally used.. Working in Xenopus egg extract, Woodward et al. found that replication speed, origin spacing, and the slowing in response to the DNA polymerase inhibitor ...
Many anticancer agents induce DNA strand breaks or cause the accumulation of DNA replication intermediates. The protein encoded by ataxia-telangiectasia mutated and Rad 3-related (ATR) generates signals in response to these altered DNA structures and activates cellular survival responses. Accordingly, ATR has drawn increased attention as a potential target for novel therapeutic strategies designed to potentiate the effects of existing drugs. In this study, we use a unique panel of genetically modified human cancer cells to unambiguously test the roles of upstream and downstream components of the ATR pathway in the responses to common therapeutic agents. Upstream, the S-phase-specific cyclin-dependent kinase (Cdk) 2 was required for robust activation of ATR in response to diverse chemotherapeutic agents. While Cdk2-mediated ATR activation promoted cell survival after treatment with many drugs, signaling from ATR directly to the checkpoint kinase Chk1 was required for survival responses to only a ...
In Eastwood and another v Magnox Electric plc; McCabe v Cornwall County Council and others, the House of Lords holds that, in cases where psychiatric injury is alleged to have been caused by acts of the employer committed prior to, and separately from the act of dismissal itself, a cause of action will exist at common law for damages.
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It was surrounded by many plant species, so it was quite impossible to determine its host, and it is beyond recognition from the flowers. Based purely on the surrounding vegetation I will make a stab at Common Broomrape and will have to visit it again next summer when the flowers will be fresh. No Thyme was found nearby (and the habitat was wrong ...
Acyclovir, famciclovir, and ganciclovir are guanosine analogs that are used as viral DNA polymerase inhibitors to treat HSV, VZV, and EBV. The three analogs require phosphorylation for activation. The first step in phosphorylation is monophosphorylation by the HSV/VZV thymidine kinase; further phosphorylation is then performed by the host cells to form the triphosphate. Finally, the drug is incorporated into the viral DNA molecule, terminating replication. Resistance arises when the virus lacks thymidine kinase and these analogs cannot be activated; therefore, cidofovir, which does not require phosphorylation by a viral kinase, must be used ...
Although N. sphaerica is often considered as a pathogen, it can also act as an endophyte depending on its host. Various studies have identified novel metabolites isolated from N. sphaerica. Some of these metabolites act as phytotoxins, while others contain antiviral or antifungal properties. The purpose of the production of many of these metabolites by the fungus are not fully understood or still unknown and is an area that needs to be further studied.[11]. Aphidicolin is a mycotoxin originally known to be produced by the fungus, Cephalosporium aphidicola. This antiviral compound was isolated in mycelium culture filtrate of N. sphaerica.[11]. Epoxyexserophilone is a metabolite similar to the phytotoxin, exserohilone. Fermentation of N. sphaerica led to the production of epoxyexserophilone. Etiolated wheat coleoptile bioassay indicated that the compound is biologically inactive, and ineffective against both gram-positive and gram-negative bacteria.[17]. Nigrosporolide is a 14-membered lactone ...
Studies of nuclear function in many organisms, especially those with tough cell walls, are limited by lack of availability of simple, economical methods for large-scale preparation of clean, undamaged nuclei. Here we present a useful method for nuclear isolation from the important model organism, the fission yeast, Schizosaccharomyces pombe. To preserve in vivo molecular configurations, we flash-froze the yeast cells in liquid nitrogen. Then we broke their tough cell walls, without damaging their nuclei, by grinding in a precision-controlled motorized mortar-and-pestle apparatus. The cryo-ground cells were resuspended and thawed in a buffer designed to preserve nuclear morphology, and the nuclei were enriched by differential centrifugation. The washed nuclei were free from contaminating nucleases and have proven well-suited as starting material for genome-wide chromatin analysis and for preparation of fragile DNA replication intermediates. We have developed a simple, reproducible, economical procedure
They permit you to browse utilizing different IP addresses from different places to make sure your actual location is protected. When you buy data heart proxies, your supplier will give an assortment of IP addresses from the places of your alternative. This provides you a lot of web freedom as a result of youll be able to browse from anyplace on the earth.. Not only are they helpful in knowledge scraping, however in addition they assist to access restricted websites and simply take pleasure in web freedom. Rotating proxies also guarantee each browsing request is distributed using a unique IP. One of probably the most primary techniques in data mining is learning to acknowledge patterns in your information units. This is often a recognition of some aberration in your knowledge taking place at common intervals, or an ebb and move of a certain variable over time.. For instance, you might see that your gross sales of a sure product appear to spike just earlier than the holidays, or discover that ...
Published: Feb 23rd, 2009. It may have been a cold night, but it was one hot party at Common Grounds Friday night. Hundreds of people showed up to the Seventh Annual Music Law Conferences […]. ...
Book appointments instantly with Dr. B. V. S. N. Raju, one of the best general physicians in Hyderabad who treats chronic illnesses and provides genuine preventive care to the patients.
We propose a model in which NOPO, a RING domain-containing protein, interacts with the BEN-UEV1A heterodimer to form a functional E2-E3 ubiquitin ligase complex required during syncytial embryogenesis for genomic integrity, cell-cycle progression, and the continuation of development (Fig. 8). In the absence of NOPO, a lack of ubiquitination of, as yet unidentified, NOPO targets results in the truncation of S-phase and/or spontaneous DNA damage. Mitotic entry with unreplicated and/or damaged DNA triggers the activation of a CHK2-mediated checkpoint that leads to changes in spindle morphology, mitotic arrest and failure of nopo-derived embryos to develop to cellularization.. We favor a model in which NOPO regulates the timing of S-M transitions in syncytial embryos to ensure that S-phase is of sufficient length to allow the completion of DNA replication prior to mitotic entry. The inhibition of DNA replication in syncytial embryos (e.g. via aphidicolin injection) leads to chromatin bridging in ...
Dapivirine, also known as TMC120, is a non-nucleoside inhibitor for HIV reverse transcriptase with IC50 of 24 nM. The HIV-1 replication inhibitor dapivirine (DPV) is one of the most promising drug candidates being used in topical microbicide products for prevention of HIV-1 sexual transmission. [last updated: 10/9/2015)
Whakapapa and science go hand in hand in a new art collaboration for a festival all about water. The Common Ground Hutt Public Art Festival has commissioned five projects that relate to water. Central to Johanna Mechen and Angela Kilfords Wairua project are conversations with Te Ati Awa iwi, community members in the Hutt Valley and scientists.
Two DNA polymerases may be required for synthesis of the lagging DNA strand of simian virus 40.: Agents discriminating between DNA polymerase alpha and DNA poly
Helianthus annuus Attracted many comments in past sunflower trials at Common Ground Fair. Stunning brown-centered 6 flowers in maroonish red with yellow tips and a hint of yellow around the center. Mixes well with other sunflowers; makes the whole bouquet pop. 3 tall. Annual. 40 seeds/g. Especially attractive to pollinators.
Recently, investigators at Universität Ulm have been investigating the low molecular weight DNA diffusion assay (LMW assay) to measure cytotoxicity in comet assays.. The comet assay is a well-established in vitro and in vivo genotoxicity test. However, there has always been concern that the comet assay (as with all DNA strand break assays) may possibly detect exposure-related cytotoxicity rather than genotoxic effects. This is because DNA degradation is frequently involved in processes leading to cell death. Concurrent measures for cytotoxicity are required for standard genotoxicity testing to assess genotoxicity and to address possible effects of cytotoxicity in comet assay data interpretation.. Typically, histopathology has been accepted as a suitable cytotoxicity detection method when using the in vivo comet assay. By looking at the histology, levels of necrosis and apoptosis can be determined. However, there are other assays available for assessing cytotoxicity.. Here, the LMW assay has ...
Isolated macronuclei from the hypotrichous ciliated protozoan Euplotes eurystomus incorporate biotinylated dUTP specifically into the replication band (RB) as detected with immunofluorescence, using rabbit anti-biotin antibodies followed by fluorescein-conjugated goat anti-rabbit IgG. When gold-conjugated goat anti-rabbit IgG was used in a preembedded reaction, subsequent immunoelectron microscopic analysis demonstrated that the biotinylated nucleotide appeared more concentrated in the rear zone of the RB, with almost no labeling in the forward zone. It was possible to use the immunofluorescent assay to establish that incorporation of biotinylated dUTP is inhibited by simultaneous addition of N-ethyl maleimide or aphidicolin, and by omission of any one of the other unlabeled dNTPs. In addition, prolonged heat shock of the intact cells, before lysis and in vitro assay, yielded markedly reduced incorporation. Comparison with published data on the in vivo incorporation of [3H]thymidine into ...
1Environmental Microbial Genomics Group, Laboratoire AMPERE, Ecole Centrale de Lyon, Université de Lyon, 36 avenue Guy de Collongue, 69134 Ecully, France. Metagenomic studies require obtaining relatively high quantities of DNA and/or high molecular weight DNA from complex environments. Furthermore, if the interest is only in procaryotic DNA, contamination by eucaryotic DNA may represent an important issue. These technical constraints depend on the type of metagenomic approach: whereas high throughput sequencing (e.g. pyrosequencing) requires several micrograms of DNA without strict size constraints, the construction of fosmid or cosmid clone libraries requires relatively lower amounts of DNA but whose size must be , 25kb. We focused here on two technical aspects: (i) obtaining procaryotic DNA free of eucaryotic contamination, and (ii) obtaining high quantities of DNA. To avoid contamination by eucaryotic DNA, an indirect extraction method is used, requiring a preliminary extraction of bacterial ...
1Environmental Microbial Genomics Group, Laboratoire AMPERE, Ecole Centrale de Lyon, Université de Lyon, 36 avenue Guy de Collongue, 69134 Ecully, France. Metagenomic studies require obtaining relatively high quantities of DNA and/or high molecular weight DNA from complex environments. Furthermore, if the interest is only in procaryotic DNA, contamination by eucaryotic DNA may represent an important issue. These technical constraints depend on the type of metagenomic approach: whereas high throughput sequencing (e.g. pyrosequencing) requires several micrograms of DNA without strict size constraints, the construction of fosmid or cosmid clone libraries requires relatively lower amounts of DNA but whose size must be , 25kb. We focused here on two technical aspects: (i) obtaining procaryotic DNA free of eucaryotic contamination, and (ii) obtaining high quantities of DNA. To avoid contamination by eucaryotic DNA, an indirect extraction method is used, requiring a preliminary extraction of bacterial ...
In a recent decision, Justice Finkelstein of the Federal Court reopened the debate surrounding the legal status of picketing and whether certified (or unregistered) agreements can operate and have effect as contracts at common law. Australia Consumer Protection Freehills 10 Jun 2004
Propofol at common clinical concentrations-is potent ventilatory depressant and therefore it is sometimes common with the name propofol respiratory depressi
Robert Ireland's synthesis of (±)-aphidicolin uses the Wolff rearrangement to do a tandem ring-contraction, and [2 + 2] ... aphidicolin and (.+-.)-.beta.-chamigrene". J. Org. Chem. 49 (6): 1001. doi:10.1021/jo00180a010. CS1 maint: Multiple names: ...
Trost, B. M.; Nishimura, Yoshio; Yamamoto, Kagetoshi (1979). "A Total Synthesis of Aphidicolin". J. Am. Chem. Soc. 101 (5): ... In 1979 Trost reported the synthesis of Aphidicolin using methodology around the vinylcyclopropane rearrangement developed in ...
FRA3A encoding protein Fragile site, aphidicolin type, common, fra(3)(p24.2). *FRMD4B encoding protein FERM domain containing ...
Aphidicolin is a mycotoxin originally known to be produced by the fungus, Cephalosporium aphidicola. This antiviral compound ... Starratt, A. N.; Loschiavo, S. R. (March 1974). "The production of aphidicolin by Nigrospora sphaerica". Canadian Journal of ...
McMurry, J. E.; Andrus A.; Ksander G. M.; Muesser, J. H.; Johnson, M. A. "Stereospecific Total Synthesis of Aphidicolin.". ...
Fragile site, aphidicolin type, common, fra(3)(p24.2) is a protein that in humans is encoded by the FRA3A gene. "Human PubMed ... Reference:". "Entrez Gene: Fragile site, aphidicolin type, common, fra(3)(p24.2)". Retrieved 2014-08-05. ...
Sensitivity to novobiocin, bacitracin, anisomycin, aphidicolin, and rifampicin have been observed. However, no sensitivity has ...
"Isolation and Characterization of Aphidicolin and Chlamydosporol Derivatives from Tolypocladium inflatum". Journal of Natural ...
"Effects of monocerin on cell cycle progression in maize root meristems synchronized with aphidicolin". Plant Cell Reports. 15: ...
The chemical agent aphidicolin can be added to easily and effectively synchronize chloroplast division. The peroxisome division ... of chloroplast division in the ultramicro-alga Cyanidioschyzon merolae by treatment with both light and aphidicolin". J. Phycol ...
"FRAXD fragile site, aphidicolin type, common, fra(X)(q27.2) D [Homo sapiens (human)] - Gene - NCBI". www.ncbi.nlm.nih.gov. " ... FRAXD or FRAXD gene is a gene symbol for fragile site, aphidicolin type, common, fra(X)(q27.2) D. The locus of the gene is ...
3-deoxyaphidicolin and aphidicolin-17-monoacetate". Nucleic Acids Res. 11: 1197-2000. doi:10.1093/nar/11.4.1197. Patrick, D.; ...
Glover, TW; Berger, C; Coyle, J; Echo, B (1984). "DNA polymerase alpha inhibition by aphidicolin induces gaps and breaks at ...
... a key enzyme responsible for formation of an unusual diterpene skeleton in biosynthesis of aphidicolin". J. Am. Chem. Soc. 123 ... "Cloning of a gene cluster responsible for the biosynthesis of diterpene aphidicolin, a specific inhibitor of DNA polymerase α ...
In the presence of DNA damage or replication stress (UV light, methyl methanesulfonate, hydroxyurea or aphidicolin), the POLD4/ ...
Further studies to support the theory of cell-proliferation were done by introducing then removing the drug aphidicolin which ...
The adozelesin-induced RPA hyperphosphorylation can be blocked by the replicative DNA polymerase inhibitor, aphidicolin, ...
Subsequent discoveries included alamethicin, aphidicolin, brefeldin A, Cephalosporin, cerulenin, citromycin, eupenifeldin, ...
... or aphidicolin, each of which had been documented to exert its effects in a particular phase of the cell cycle. Surprisingly, ...
Aphidicolin Experimental drugs and drug precursors: Parthenolide, Puromycin, Rapamycin, Anisomycin, Thapsigargin, cyclopamine, ...
... aphidicolin type, common, fra(3)(p24.2) FRMD4B encoding protein FERM domain containing 4B GMPPB: GDP-mannose pyrophosphorylase ...
... aphidicolin MeSH D02.455.849.291.162 --- atractyloside MeSH D02.455.849.291.206 --- diterpenes, abietane MeSH D02.455.849.291. ...
Most notable are prostaglandin F2a, narwedine, aphidicolin, taxusin, Taxol and hemibrevitoxin B. Dr. Holton also serves as ...
ISBN 978-0-12-465327-6. DeFilippes, FM (Nov 1984). "Effect of aphidicolin on vaccinia virus: isolation of an aphidicolin- ... Aphidicolin is a reversible inhibitor of eukaryotic nuclear DNA replication. It blocks the cell cycle at early S phase. It is a ... Natural aphidicolin is a secondary metabolite of the fungus Nigrospora oryzae. Dhillon VS, Husain SA, Ray GN (2003). " ... Aphidicolin is a tetracyclic diterpene antibiotic isolated from the fungus, Cephalosporum aphidicola with antiviral and ...
7-Dehydrocholesterol is the precursor of cholecalciferol.[8] Within the epidermal layer of skin, 7-dehydrocholesterol undergoes an electrocyclic reaction as a result of UVB light at wavelengths between 290 and 315 nm, with peak synthesis occurring between 295 and 300 nm.[32] This results in the opening of the vitamin precursor B-ring through a conrotatory pathway making previtamin D3 (pre-cholecalciferol).[33] In a process which is independent of UV light, the pre-cholecalciferol then undergoes a [1,7] antarafacial sigmatropic rearrangement [34] and therein finally isomerizes to form vitamin D3. The active UVB wavelengths are present in sunlight, and sufficient amounts of cholecalciferol can be produced with moderate exposure of the skin, depending on the strength of the sun.[32] Time of day, season, and altitude affect the strength of the sun, and pollution, cloud cover or glass all reduce the amount of UVB exposure. Exposure of face, arms and legs, averaging 5-30 minutes twice per week, may be ...
ISBN 978-0-12-465327-6. DeFilippes, FM (Nov 1984). "Effect of aphidicolin on vaccinia virus: isolation of an aphidicolin- ... Aphidicolin is a reversible inhibitor of eukaryotic nuclear DNA replication. It blocks the cell cycle at early S phase. It is a ... Natural aphidicolin is a secondary metabolite of the fungus Nigrospora oryzae. Dhillon VS, Husain SA, Ray GN (2003). " ... Aphidicolin is a tetracyclic diterpene antibiotic isolated from the fungus, Cephalosporum aphidicola with antiviral and ...
G2 and G1 phases after Aphidicolin synchronization. For this purpose we measured diffusion rates of EGFP molecules using ... Aphidicolin synchronization influences cell size. HeLa cells were synchronized by incubation with aphidicolin (5 µg/ml) for 24 ... Aphidicolin synchronization. Ready-made aphidicolin solution (1 mg/ml) was purchased from Sigma-Aldrich (USA). Cells were ... Aphidicolin efficiently synchronizes HeLa cells. First, we tested if addition of aphidicolin indeed would allow robust ...
Aphidicolin, CAS: 38966-21-1, is a novel tetracyclic diterpene antibiotic and also a DNA synthesis inhibitor in eukaryotes.. ... Aphidicolin is useful for cell synchronization. Aphidicolin blocks the cell cycle at early S phase. Aphidicolin prolongs the ... Aphidicolin (CAS 38966-21-1) Aphidicolin , CAS 38966-21-1 is rated 5.0 out of 5 by 3. ... Aphidicolin (CAS 38966-21-1) Product Citations See how others have used Aphidicolin (CAS 38966-21-1). Click on the entry to ...
Inhibition of DNA repair with aphidicolin enhances sensitivity of targets to tumor necrosis factor.. J F Gera, C Fady, A ... Aphidicolin inhibited repair and consistently sensitized to TNF cytotoxicity, decreasing the ID50 for TNF at least 10- to 50- ... In targets sensitized with aphidicolin, TNF-induced strand breakage was accelerated, being detected by 4 h of culture in the ... To inhibit repair, nontoxic concentrations of aphidicolin (inhibitor of DNA polymerase-alpha) and dideoxythymidine (inhibitor ...
C growth medium and 6 μM aphidicolin (catalog no. 10797; Fluka). The nocodazole and aphidicolin were both dissolved in dimethyl ... Because exposure to aphidicolin causes cell cycle arrest in the G1/S stage for both T. brucei and Giardia, it can be assumed ... A and B) Subjecting a control culture with a 5:1 ratio of G2 to G1 cells (A) to treatment with 6 μM aphidicolin (Aph) for 6 h ... Arrest of Giardia cell cycle with nocodazole and aphidicolin. (A) Starting culture with a 5:1 ratio of G2 to G1 cells. (B) ...
2705 (1973). [3] Aphidicolin: (a) E. J . Corey, M.A . Tius, J. Das. J. Am. Chem. SOC.102. 1744 (1980); J. E. McMurry, A . ... An Expeditious and Efficient Entry into the Aphidicolin and Related Natural Products Ring Skeleton.. код для вставки. код для ... The strategy for this new entry into the aphidicolin (1) and related structures depends on two key operations; firstly a ... An Expeditious and Efficient Entry into the Aphidicolin and Related Natural Products Ring Skeleton**] By K . C. Nicolaou and ...
Purification of the cdc8 protein of Saccharomyces cerevisiae by complementation in an aphidicolin-sensitive in vitro DNA ... Purification of the cdc8 protein of Saccharomyces cerevisiae by complementation in an aphidicolin-sensitive in vitro DNA ...
Aphidicolin (CAS 38966-21-1) specifically inhibits DNA polymerase α & δ, arresting the cell cycle at early S phase while ... Aphidicolin , DNA polymerase inhibitor Aphidicolin (38966-21-1) specifically inhibits DNA polymerase α and δ via binding to the ... Aphidicolin potentiates apoptosis induction induced by other agents3. Increases gene amplification frequency in HeLa S3 cells ... 1993), Aphidicolin potentiates apoptosis induced by arabinosyl nucleosides in human myeloid leukemia cell lines; Biochem. ...
HomeThe G1/S inhibitor aphidicolin neither affec. The G1/S inhibitor aphidicolin neither affec. By admin June 11, 2019 ...
Aphidicolin-resistant recombinant progeny were formed with recombination frequencies (0.4 to 2.6%) compatible with intragenic ... A wide range of stable aphidicolin sensitivities was represented amongst a collection of virus strains with no prior exposure ... Of 16 unrelated PAA-resistant variants, 7 were hypersensitive to aphidicolin. A number of mutants with temperature-sensitive ( ... ts) lesions in the polymerase gene also showed increased aphidicolin sensitivity (e.g. HSV-1[mP17]tsH) or aphidicolin ...
Aphidicolin treatments. Embryos were incubated for 2 hours (from 70% epiboly to the 3-somite stage) [compared to an estimated 4 ... Marheineke, K. and Hyrien, O. (2001). Aphidicolin triggers a block to replication origin firing in Xenopus egg extracts. J. ... To block cell proliferation, we incubated wild-type embryos in aphidicolin from the onset of her5 expression until early ... in embryo medium containing 1 or 10 μg/ml aphidicolin (Sigma A-9914) at 28.5°C (Marheineke and Hyrien, 2001). The embryos were ...
Robert Irelands synthesis of (±)-aphidicolin uses the Wolff rearrangement to do a tandem ring-contraction, and [2 + 2] ... aphidicolin and (.+-.)-.beta.-chamigrene". J. Org. Chem. 49 (6): 1001. doi:10.1021/jo00180a010. CS1 maint: Multiple names: ...
Aphidicolin promotes repair of potentially lethal damage in irradiated mammalian cell synchronized in s-phase. ... Iliakis, G and Nusse, M, "Aphidicolin promotes repair of potentially lethal damage in irradiated mammalian cell synchronized in ...
Aphidicolin (APH), a tetracyclic diterpene, exhibits specific cytotoxic action against NB cells. The purpose of this study was ... Treatment of drug-resistant human neuroblastoma cells with cyclodextrin inclusion complexes of aphidicolin. ... Treatment of drug-resistant human neuroblastoma cells with cyclodextrin inclusion complexes of aphidicolin. Anti-cancer drugs, ...
Hydroxyurea and aphidicolin (HUA) treatment. HUA treatment was performed as described previously (Harris and Hartenstein, 1991 ... hydroxyurea and aphidicolin (HUA; supplementary material Fig. S2A-E) (Harris and Hartenstein, 1991). When soaked in HUA ... 150 mM aphidicolin (A0781; Sigma) and 0.1× MMR] until the desired stages. ...
Aphidicolin Type, Common, Fra(6)(Q15), including: function, proteins, disorders, pathways, orthologs, and expression. GeneCards ... FRA6G (Fragile Site, Aphidicolin Type, Common, Fra(6)(Q15)) is an Uncategorized gene. ...
... and then treated with aphidicolin for 3 h before nucleofection. The duration of aphidicolin treatment was shortened, because a ... Aphidicolin was the only tested treatment that enhanced NHEJ and HDR. The NHEJ frequency increased from 8% to 18% at 30 ρmol ... Aphidicolin and nocodazole increased the NHEJ frequency slightly at 30 ρmol of Cas9; at 100 ρmol of Cas9, the detection limit ... Aphidicolin was added into the growth media immediately after nucleofection to 2 μg/ml. The mean % HDR and standard deviation ( ...
... aphidicolin) and interference with enzymes dealing with topological DNA stress (camptothecin, etoposide). As a variety of ... Keywords: replication stress; cisplatin; aphidicolin; hydroxyurea; camptothecin; etoposide; cancer replication stress; ... aphidicolin) and interference with enzymes dealing with topological DNA stress (camptothecin, etoposide). As a variety of ...
Differential effects of aphidicolin on replicative dna synthesis and unscheduled dna synthesis in permeable mouse sarcoma cells ... Seki, S; Oda, T; and Ohashi, M, "Differential effects of aphidicolin on replicative dna synthesis and unscheduled dna synthesis ...
Aphidicolin Type, Common, Fra(X)(P22.31) B, including: function, proteins, disorders, pathways, orthologs, and expression. ... FRAXB (Fragile Site, Aphidicolin Type, Common, Fra(X)(P22.31) B) is an Uncategorized gene. ...
DNA polymerase inhibitor aphidicolin; RNA polymerase inhibitor actinomycin D; protein synthesis inhibitor cycloheximide; ...
Aphidicolin and Eukaryotic DNA Synthesis. Spadari, Silvio (et al.). Pages 169-181 ...
All the above mentioned processes of DNA synthesis are reversibly inhibited by aphidicolin (C50 from 3-13 microM). From the ...
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The biosynthesis of aphidicolin. J Gordon. Brighton : University of Sussex, 1986.. Online access ...
  • Aphidicolin is a reversible inhibitor of eukaryotic nuclear DNA replication. (wikipedia.org)
  • Aphidicolin: a specific inhibitor of nuclear DNA replication in eukaryotes: S. Spadari, et al. (nordicbiosite.com)
  • atr mutants are sensitive to replication-blocking agents including HU and aphidicolin and to UVB light ( 9 ). (pnas.org)
  • The interaction between claspin and DNA was increased by the addition of the restriction enzyme Eco RI to cause DSBs or aphidicolin to stall DNA replication. (sciencemag.org)
  • Immunodepletion of claspin alone blocked phosphorylation of Chk1 in response to aphidicolin-induced stalled DNA replication forks. (sciencemag.org)
  • mutated 12 potential phosphorylation sites in claspin that matched the consensus motif for ATR-mediated phosphorylation and found that activation of Chk1 in response to aphidicolin-induced stalled replication forks was unaffected, whereas the activation of Chk1 in response to DSBs was decreased. (sciencemag.org)
  • Aphidicolin inhibited repair and consistently sensitized to TNF cytotoxicity, decreasing the ID50 for TNF at least 10- to 50-fold. (jimmunol.org)
  • One study which did address this topic used flow cytometry or elutriation of synchronized cells treated with actinomycin D1, camptothecin, or aphidicolin, each of which had been documented to exert its effects in a particular phase of the cell cycle. (wikipedia.org)
  • In this paper we address this topic by constant observation of nanoviscosity of HeLa cells cytoplasm during S, G2 and G1 phases after Aphidicolin synchronization. (nature.com)
  • Fragile site, aphidicolin type, common, fra(3)(p24.2) is a protein that in humans is encoded by the FRA3A gene. (wikipedia.org)
  • Despite not sharing structural homology with dCTP (deoxycytidine triphosphate) aphidicolin binds at this nucleotide-binding site 18 . (nature.com)
  • FRAXD or FRAXD gene is a gene symbol for fragile site, aphidicolin type, common, fra(X)(q27.2) D. The locus of the gene is located on fragile site of the q arm of chromosome X at position 27.2. (wikipedia.org)
  • Aphidicolin is a specific inhibitor of DNA polymerase α and δ in eukaryotic cells and in some viruses of animal origin. (scbt.com)
  • In medicine, Aphidicolin 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. (scbt.com)
  • Aphidicolin (APH), a tetracyclic diterpene, exhibits specific cytotoxic action against NB cells. (kent.ac.uk)
  • Aphidicolin-induced nuclear elongation in tobacco BY-2 cells: H. Yashura, et al. (nordicbiosite.com)
  • In the present study, we tested whether aphidicolin encapsulated in liposomes kills NB cells with the efficacy superior to that of unencapsulated aphidicolin. (sav.sk)
  • The treatment with encapsulated aphidicolin at a concentration of 200 nmol for 5 days killed all cells of three human NB cell lines. (sav.sk)
  • In contrast, at least 30% of the cells survived 5 days of treatment with 200 nmol unencapsulated aphidicolin. (sav.sk)
  • The results showed that aphidicolin killing of human NB cells may be increased by encapsulation in liposomes. (sav.sk)
  • Detection of proliferation using the Click-iT EdU microplate assay with aphidicolin-treated cells. (thermofisher.com)
  • The infectivity of wild-type and mutant SIVmac239 was not decreased by aphidicolin-induced growth arrest of the target cells. (asm.org)
  • G2 arrest also was observed in wild-type plants in response to aphidicolin but was defective in atr mutants, resulting in compaction of nuclei and subsequent cell death. (plantcell.org)
  • Time-lapse videomicroscopy of aphidicolin-treated extracts revealed that nuclear envelope breakdown did not occur during the 6-hour experiment ( 20 ). (sciencemag.org)
  • Embryonic day 15 rat dorsal root ganglia (DRG) were cultured on nanofibers for 3 days in defined media, both with and without aphidicolin, which prevented Schwann cell proliferation. (minervamedica.it)
  • An Expeditious and Efficient Entry into the Aphidicolin and Related Natural Products Ring Skeleton. (docme.ru)
  • Aphidicolin is a diterpene fungal metabolite that blocks the cell cycle at early S-phase. (scbt.com)
  • Aphidicolin blocks the cell cycle at early S phase. (scbt.com)
  • Aphidicolin promotes repair of potentially lethal damage in irradiated mammalian cell synchronized in s-phase. (jax.org)
  • Aphidicolin prevents mitotic cell division by interfering with the activity of DNA polymerase-alpha: S. Ikegami, et al. (nordicbiosite.com)
  • in contrast, H1 activity in aphidicolin-treated extracts remained at a constant, low amount for 6 hours ( 20 , 21 ). (sciencemag.org)
  • Unexpectedly, aphidicolin decreased the distance SC migrated on glass, but had no effect on SC migration on nanofibers. (minervamedica.it)
  • Human papillomavirus episome stability is reduced by aphidicolin and controlled by DNA damage response pathways: T. G. Edwards, et al. (nordicbiosite.com)