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41.
The when and wheres of CDC25 phosphatases   总被引:14,自引:0,他引:14  
The CDC25 phosphatases are key regulators of normal cell division and the cell's response to DNA damage. Earlier studies suggested non-overlapping roles for each isoform during a specific cell cycle phase. However, recent data suggest that multiple CDC25 isoforms cooperate to regulate each cell cycle transition. For instance, although CDC25A was initially thought to exclusively regulate the G(1)-S transition, recent data demonstrate a significant role for CDC25A in the G(2)-M transition. Further evidence demonstrates that in addition to the ATM/ATR-CHK pathway, a p38-MAPKAP pathway is also involved in controlling CDC25 activity during G(2)/M checkpoint activation. Together with the fact that CDC25 overexpression is reported in many cancers, these data highlight the significance of developing specific CDC25 inhibitors for cancer therapy.  相似文献   
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This study aimed to evaluate the role of APOE polymorphisms (rs429358 and rs7412) in the risk of age-related macular degeneration in a sample of the Southeastern Brazilian population. Seven hundred and five unrelated individuals were analyzed, 334 with age-related macular degeneration (case group), and 371 without the disease (control group). In the case group, patients were further stratified according to disease phenotypes, divided into dry and wet age-related macular degeneration, and non-advanced and advanced age-related macular degeneration. APOE polymorphisms (rs429358 and rs7412) were evaluated through polymerase chain reaction and direct sequencing. In the comparison of cases vs. controls, none of the associations reached statistical significance, considering the Bonferroni-adjusted P-value, although there was a suggestive protection for the E3/E4 genotype (OR = 0.626; P-value = 0.037) and E4 carriers (OR = 0.6515; P-value = 0.047). Statistically significant protection for both the E3/E4 genotype and E4 carriers was observed in the comparisons: advanced age-related macular degeneration vs. controls (OR = 0.3665, P-value = 0.491 × 10−3 and OR = 0.4031, P-value = 0.814 × 10−3, respectively), advanced age-related macular degeneration vs. non-advanced age-related macular degeneration (OR = 0.2529, P-value = 0.659 × 10−4 and OR = 0.2692, P-value = 0.631 × 10−4, respectively). In the comparison of wet age-related macular degeneration vs. control, protection was statistically significant only for E3/E4 (OR = 0.4052, P-value = 0.001). None of the comparisons demonstrated any significant association for E2 genotypes or E2 carriers in age-related macular degeneration risk in this study. Findings suggest a protective role of the E4 haplotype in the APOE gene in the risk for advanced and wet forms of age-related macular degeneration, in a sample of the Brazilian population. To our knowledge, this is the first Brazilian study to show the association between APOE polymorphisms and age-related macular degeneration.  相似文献   
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The tumor protein D52 family: many pieces, many puzzles   总被引:4,自引:0,他引:4  
Tumor protein D52-like proteins are small coiled-coil motif bearing proteins which are conserved from lower organisms to human. The founding member of the family, human D52, has principally attracted research interest due to its frequent overexpression in cancer, often in association with D52 gene amplification. This review summarises published literature concerning this protein family since their discovery, which is highlighting an increasing diversity of functions for D52-like proteins. This in turn highlights a need for more comparative functional analyses, to determine which functions are conserved and which may be isoform-specific. This knowledge will be crucial for any future manipulation of D52 function in human disease, including cancer.  相似文献   
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Chlor-Floc (CF) emergency water purification tablets were tested for bactericidal, virucidal, and cysticidal efficacy in water at temperatures ranging from 5 to 25°C. The minimal required log reduction was achieved for bacteria, Giardia muris, and rotavirus, but CF did not achieve the required log reduction of poliovirus at any of the temperatures or times investigated. The biocidal properties of the CF tablet were equivalent to if not greater than those of the Globaline iodine tablet, and the CF tablet was a more rapid cysticide under several potential use conditions. Therefore, it is a suitable substitute for iodine tablets for emergency purification of drinking water. Clarification of turbid waters was effective, but filtration through a cloth is necessary to prevent flocculated sediment from entering the canteen. The CF tablets met military requirements for emergency water purification and are safe and acceptable for use by the military.  相似文献   
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During the development of multicellular organisms the formation of complex patterns relies on specific cell-cell signaling events. For tissues to become spatially organized and cells to become committed to specialized fates it is absolutely crucial for proper development that the underlying signaling systems receive and route information correctly. Recently, a wealth of genetic and biochemical experimental data has been collected about prevalent evolutionary conserved signaling families, such as the Wnts, Dpp/BMPs, and Hedgehogs, in flies, worms, and vertebrates. Paradoxically, members of a particular signaling family often have receptors with similar biochemical binding properties, though they activate different intracellular pathways in vivo and can be phenotypically distinguished. How are their specific biological responses then generated? With respect to signaling specificity in Wnt pathways, Dishevelled is an intriguing protein; in Drosophila melanogaster it is required in two distinct signaling pathways, that share Frizzled receptors of similar structure, but have distinct intracellular signaling routes. Recent results suggest that Dishevelled is a multifunctional protein at the crossroads of divergent Wnt/Fz pathways. Dishevelled appears to be a key factor in Wnt signaling to read' signals coming from the plasma membrane and route them into the correct intracellular pathways.  相似文献   
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Secretion of Wnt ligands requires Evi, a conserved transmembrane protein   总被引:8,自引:0,他引:8  
Wnt signaling pathways are important for multiple biological processes during development and disease. Wnt proteins are secreted factors that activate target-gene expression in both a short- and long-range manner. Currently, little is known about how Wnts are released from cells and which factors facilitate their secretion. Here, we identify a conserved multipass transmembrane protein, Evenness interrupted (Evi/Wls), through an RNAi survey for transmembrane proteins involved in Drosophila Wingless (Wg) signaling. During development, evi mutants have patterning defects that phenocopy wg loss-of-function alleles and fail to express Wg target genes. evi's function is evolutionarily conserved as depletion of its human homolog disrupts Wnt signaling in human cells. Epistasis experiments and clonal analysis place evi in the Wg-producing cell. Our results show that Wg is retained by evi mutant cells and suggest that evi is the founding member of a gene family specifically required for Wg/Wnt secretion.  相似文献   
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