Biomaterial Database

Cell cycle dependent subcellular distribution of Cdc25B subtypes. 1999

E S Woo, and R L Rice, and J S Lazo

Department of Pharmacology, University of Pittsburgh Cancer Institute, University of Pittsburgh, Pennsylvania 15261, USA.

The dual specificity phosphatase and oncogene Cdc25B has been implicated in the G2/M cell cycle checkpoint, but the mode by which it is regulated remains poorly understood. Regional subcellular redistribution of proteins represents a unique potential regulatory mechanism. Thus, we examined in live cells the subcellular localization characteristics of Cdc25B2 and Cdc25B3 fused to green fluorescent protein. Cdc25B2 partitioned primarily in the cytoplasm during G1 and progressively migrated to the nucleus as cells transited from S to G2/M phase. In contrast, Cdc25B3 maintained a homogeneously staining diffuse phenotype irrespective of cell cycle phase. Treatment of the Cdc25B2-green fluorescent protein stable transfectants with vanadate inhibited the cell cycle dependency of intracellular distribution, while okadaic acid had little effect except in G1, suggesting regulation by at least one phosphorylation-dependent pathway. The DNA topoisomerase II poison and DNA damaging agent, etoposide, inhibited nuclear localization of Cdc25B2 in S phase, possibly by invoking a sequestration cascade. Thus, differences in the spatial distribution of Cdc25B subtypes exist within cells and the 41 amino acid insert in the N-terminus of the Cdc25B3 splice variant encodes an important inhibitory determinant for such regulation. The subcellular redistribution of Cdc25B2 could be functionally important for G2/M checkpoint regulation.

UI	MeSH Term	Description	Entries
D008164	Luminescent Proteins	Proteins which are involved in the phenomenon of light emission in living systems. Included are the "enzymatic" and "non-enzymatic" types of system with or without the presence of oxygen or co-factors.	Bioluminescent Protein,Bioluminescent Proteins,Luminescent Protein,Photoprotein,Photoproteins,Protein, Bioluminescent,Protein, Luminescent,Proteins, Bioluminescent,Proteins, Luminescent
D010641	Phenotype	The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.	Phenotypes
D010749	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)	Phosphoprotein Phosphatase,Phosphoprotein Phosphohydrolase,Protein Phosphatase,Protein Phosphatases,Casein Phosphatase,Ecto-Phosphoprotein Phosphatase,Nuclear Protein Phosphatase,Phosphohistone Phosphatase,Phosphoprotein Phosphatase-2C,Phosphoseryl-Protein Phosphatase,Protein Phosphatase C,Protein Phosphatase C-I,Protein Phosphatase C-II,Protein Phosphatase H-II,Protein-Serine-Threonine Phosphatase,Protein-Threonine Phosphatase,Serine-Threonine Phosphatase,Threonine Phosphatase,Ecto Phosphoprotein Phosphatase,Phosphatase C, Protein,Phosphatase C-I, Protein,Phosphatase C-II, Protein,Phosphatase H-II, Protein,Phosphatase, Casein,Phosphatase, Ecto-Phosphoprotein,Phosphatase, Nuclear Protein,Phosphatase, Phosphohistone,Phosphatase, Phosphoprotein,Phosphatase, Phosphoseryl-Protein,Phosphatase, Protein,Phosphatase, Protein-Serine-Threonine,Phosphatase, Protein-Threonine,Phosphatase, Serine-Threonine,Phosphatase, Threonine,Phosphatase-2C, Phosphoprotein,Phosphatases, Phosphoprotein,Phosphatases, Protein,Phosphohydrolase, Phosphoprotein,Phosphoprotein Phosphatase 2C,Phosphoseryl Protein Phosphatase,Protein Phosphatase C I,Protein Phosphatase C II,Protein Phosphatase H II,Protein Phosphatase, Nuclear,Protein Serine Threonine Phosphatase,Protein Threonine Phosphatase,Serine Threonine Phosphatase
D010766	Phosphorylation	The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.	Phosphorylations
D011993	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.	Fusion Proteins, Recombinant,Recombinant Chimeric Protein,Recombinant Fusion Protein,Recombinant Hybrid Protein,Chimeric Proteins, Recombinant,Hybrid Proteins, Recombinant,Recombinant Chimeric Proteins,Recombinant Hybrid Proteins,Chimeric Protein, Recombinant,Fusion Protein, Recombinant,Hybrid Protein, Recombinant,Protein, Recombinant Chimeric,Protein, Recombinant Fusion,Protein, Recombinant Hybrid,Proteins, Recombinant Chimeric,Proteins, Recombinant Fusion,Proteins, Recombinant Hybrid
D002453	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.	Cell Division Cycle,Cell Cycles,Cell Division Cycles,Cycle, Cell,Cycle, Cell Division,Cycles, Cell,Cycles, Cell Division,Division Cycle, Cell,Division Cycles, Cell
D004249	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.	DNA Injury,DNA Lesion,DNA Lesions,Genotoxic Stress,Stress, Genotoxic,Injury, DNA,DNA Injuries
D004791	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.	Enzyme Inhibitor,Inhibitor, Enzyme,Inhibitors, Enzyme
D005047	Etoposide	A semisynthetic derivative of PODOPHYLLOTOXIN that exhibits antitumor activity. Etoposide inhibits DNA synthesis by forming a complex with topoisomerase II and DNA. This complex induces breaks in double stranded DNA and prevents repair by topoisomerase II binding. Accumulated breaks in DNA prevent entry into the mitotic phase of cell division, and lead to cell death. Etoposide acts primarily in the G2 and S phases of the cell cycle.	Demethyl Epipodophyllotoxin Ethylidine Glucoside,Celltop,Eposide,Eposin,Eto-GRY,Etomedac,Etopos,Etoposide Pierre Fabre,Etoposide Teva,Etoposide, (5S)-Isomer,Etoposide, (5a alpha)-Isomer,Etoposide, (5a alpha,9 alpha)-Isomer,Etoposide, alpha-D-Glucopyranosyl Isomer,Etoposido Ferrer Farma,Exitop,Lastet,NSC-141540,Onkoposid,Riboposid,Toposar,VP 16-213,VP-16,Vepesid,Vépéside-Sandoz,Eto GRY,Etoposide, alpha D Glucopyranosyl Isomer,NSC 141540,NSC141540,Teva, Etoposide,VP 16,VP 16 213,VP 16213,VP16,Vépéside Sandoz,alpha-D-Glucopyranosyl Isomer Etoposide
D006224	Cricetinae	A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.	Cricetus,Hamsters,Hamster