Abstract：
:The catalytic subunit of DNA-dependent protein kinase (DNA-PKcs) is the key functional element in the DNA-PK complex that drives nonhomologous end joining (NHEJ), the predominant DNA double-strand break (DSB) repair mechanism operating to rejoin such breaks in mammalian cells after exposure to ionizing radiation. It has been reported that DNA-PKcs phosphorylation and kinase activity are critical determinants of radiosensitivity, based on responses reported after irradiation of asynchronously dividing populations of various mutant cell lines. In the present study, the relative radiosensitivity to cell killing as well as chromosomal instability of 13 DNA-PKcs site-directed mutant cell lines (defective at phosphorylation sites or kinase activity) were examined after exposure of synchronized G(1) cells to (137)Cs γ rays. DNA-PKcs mutant cells defective in phosphorylation at multiple sites within the T2609 cluster or within the PI3K domain displayed extreme radiosensitivity. Cells defective at the S2056 cluster or T2609 single site alone were only mildly radiosensitive, but cells defective at even one site in both the S2056 and T2609 clusters were maximally radiosensitive. Thus a synergism between the capacity for phosphorylation at the S2056 and T2609 clusters was found to be critical for induction of radiosensitivity.
journal_name
Radiat Resjournal_title
Radiation researchauthors
Nagasawa H,Little JB,Lin YF,So S,Kurimasa A,Peng Y,Brogan JR,Chen DJ,Bedford JS,Chen BPdoi
10.1667/RR2092.1subject
Has Abstractpub_date
2011-01-01 00:00:00pages
83-9issue
1eissn
0033-7587issn
1938-5404pii
10.1667/RR2092.1journal_volume
175pub_type
杂志文章abstract：:The molecular basis of radiotherapy-related multidrug resistance (MDR) is still unclear. Here we report on a study investigating the effect of fractionated irradiation on expression of the MDR-associated proteins P-glycoprotein (P-gp), multidrug resistance-associated protein (MRP), and lung resistance-related protein ...
journal_title：Radiation research
pub_type： 杂志文章
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更新日期：2008-07-01 00:00:00
abstract：:Evaluation of the characteristics of accelerator-based thermal neutron fields is recognized as an important issue when discussing the effectiveness of boron neutron capture therapy (BNCT). In this study, we propose that the radiation chemical yield (G value) of hydroxyl radicals (Goh•) can be considered a universal pa...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR15318.1
更新日期：2019-05-01 00:00:00
abstract：:Previous work from our laboratory suggested that neuronal chromatin structure may be altered immediately after exposure to ionizing radiation. In the present study, whole brains of 4-month-old male Fisher 344 rats were irradiated with a dose of 25 Gy. The kinetics of restoring the chromatin structure to its unirradiat...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1988-04-01 00:00:00
abstract：:Mice were irradiated with 1 Gy of fission neutrons. At intervals up to 15 days after irradiation undifferentiated spermatogonia were counted in whole mounts of seminiferous tubules in up to eight stages of the epithelial cycle. From Day 6 onward lower numbers of spermatogonia were found in the areas which were in stag...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1984-03-01 00:00:00
abstract：:Mixed radiation fields comprise the most common form of radiation exposure. Given their relevance in radiation protection, cancer radiotherapy and space research, accurate predictions of the corresponding radiation effects are essential. The local effect model (LEM) allows the prediction of cell survival after ion irr...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR15456.1
更新日期：2020-02-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章,评审
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更新日期：2005-10-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/0033-7587(2001)156[0186:geohei]2.0.co;2
更新日期：2001-08-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR15459.1
更新日期：2020-01-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/0033-7587(2005)163[0364:doosib]2.0.co;2
更新日期：2005-04-01 00:00:00
abstract：:Radiation-induced cell death is thought to be caused by nuclear DNA damage that cannot be repaired. However, in this study we found that a delayed increase of mitochondrial reactive oxygen species (ROS) is responsible for some of the radiation-induced cell death in normal human fibroblast cells. We have previously rep...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR13772.1
更新日期：2015-04-01 00:00:00
abstract：:Chinese hamster V79 cells show a complex X-ray survival response which is characterized by hypersensitivity followed by increased resistance as the dose increases to 1 Gy. This hypersensitivity can be eliminated by pretreating cells with X rays or hydrogen peroxide. Accordingly, the protective effect that results from...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1996-10-01 00:00:00
abstract：:Current therapeutic approaches for treatment of exposure to radiation involve the use of antioxidants, chelating agents, recombinant growth factors and transplantation of stem cells (e.g., hematopoietic stem cell transplantation). However, exposure to high-dose radiation is associated with severe damage to the vascula...
journal_title：Radiation research
pub_type： 杂志文章,评审
doi：10.1667/RR14461.1
更新日期：2016-08-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1984-04-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1991-03-01 00:00:00
abstract：:Cellular and molecular repair was studied at 23 degrees C using split-dose recovery and alkaline elution techniques, respectively, as a function of cellular oxygen and nutrient conditions. Hypoxic cells (0.001% O2) in full medium showed a partial reduction in the level of sublethal damage (SLD) repair relative to aera...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1985-01-01 00:00:00
abstract：:The capacity of plateau-phase Chinese hamster V79 and normal and transformed C3H-10T1/2 cells for repair of potentially lethal radiation damage (PLD) was evaluated for cells irradiated alone or given combined treatments of heat and radiation. The data show that all cell lines tested could repair PLD and that transform...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1988-01-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR1453.1
更新日期：2009-03-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/0033-7587(2001)156[0603:poriia]2.0.co;2
更新日期：2001-11-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1962-06-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1985-08-01 00:00:00
abstract：:Evaluation of the probability of biological phenomena per cell by colony formation, requires knowledge not only of the number of cells at risk but also of their microdistribution. In the present study, the influence of cellular multiplicity (number of cells per potential colony-forming unit) on the determination of ra...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1994-06-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1998-08-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/0033-7587(2000)153[0479:pddihb]2.0.co;2
更新日期：2000-04-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1999-04-01 00:00:00
abstract：:Dose assessment after radiological disasters is imperative to decrease mortality through rationally directed medical intervention. Our goal was to identify biomarkers capable of qualitative (nonirradiated/irradiated) and/or quantitative (dose) assessment of radiation exposure. Using real-time quantitative PCR, biodosi...
journal_title：Radiation research
pub_type： 杂志文章
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更新日期：2011-07-01 00:00:00
abstract：:The detection of (41)Ca atoms in tooth enamel using accelerator mass spectrometry is suggested as a method capable of reconstructing thermal neutron exposures from atomic bomb survivors in Hiroshima and Nagasaki. In general, (41)Ca atoms are produced via thermal neutron capture by stable (40)Ca. Thus any (41)Ca atoms ...
journal_title：Radiation research
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更新日期：2010-08-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/0033-7587(2000)154[0537:tdashd]2.0.co;2
更新日期：2000-11-01 00:00:00
abstract：:An understanding of proton radiobiology is critical for optimization of both proton radiotherapy and assessment of carcinogenesis risk from space radiation. Although the physical aspects of proton beam radiobiology is well understood, the biological aspects, particularly the complex biological end points, have been un...
journal_title：Radiation research
pub_type： 杂志文章,评审
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更新日期：2013-03-01 00:00:00
abstract：:Base damage flanking a radiation-induced DNA double-strand break (DSB) may contribute to DSB complexity and affect break repair. However, to date, an isolated radiation-induced DSB has not been assessed for such structures at the molecular level. In this study, an authentic site-specific radiation-induced DSB was prod...
journal_title：Radiation research
pub_type： 杂志文章
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更新日期：2006-11-01 00:00:00
abstract：:Molecular oxygen has long been recognized as a powerful radiosensitizer that enhances the cell-killing efficiency of ionizing radiation. Radiosensitization by oxygen occurs at very low concentrations with the half-maximum radiosensitization at approximately 3 mmHg. However, robust hypoxia-induced signal transduction c...
journal_title：Radiation research
pub_type： 杂志文章,评审
doi：10.1667/RR13959.1
更新日期：2015-05-01 00:00:00
