کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1937730 1050724 2007 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Deficiency in the response to DNA double-strand breaks in mouse early preimplantation embryos
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی زیست شیمی
پیش نمایش صفحه اول مقاله
Deficiency in the response to DNA double-strand breaks in mouse early preimplantation embryos
چکیده انگلیسی

DNA double-strand breaks (DSBs) are caused by various environmental stresses, such as ionizing radiation and DNA-damaging agents. When DSBs occur, cell cycle checkpoint mechanisms function to stop the cell cycle until all DSBs are repaired; the phosphorylation of H2AX plays an important role in this process. Mouse preimplantation-stage embryos are hypersensitive to ionizing radiation, and X-irradiated mouse zygotes are arrested at the G2 phase of the first cell cycle. To investigate the mechanisms responding to DNA damage at G2 in mouse preimplantation embryos, we examined G2/M checkpoint and DNA repair mechanisms in these embryos. Most of the one- and two-cell embryos in which DSBs had been induced by γ-irradiation underwent a delay in cleavage and ceased development before the blastocyst stage. In these embryos, phosphorylated H2AX (γ-H2AX) was not detected in the one- or two-cell stages by immunocytochemistry, although it was detected after the two-cell stage during preimplantation development. These results suggest that the G2/M checkpoint and DNA repair mechanisms have insufficient function in one- and two-cell embryos, causing hypersensitivity to γ-irradiation. In addition, phosphorylated ataxia telangiectasia mutated protein and DNA protein kinase catalytic subunits, which phosphorylate H2AX, were detected in the embryos at one- and two-cell stages, as well as at other preimplantation stages, suggesting that the absence of γ-H2AX in one- and two-cell embryos depends on some factor(s) other than these kinases.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Biochemical and Biophysical Research Communications - Volume 358, Issue 2, 29 June 2007, Pages 578–584
نویسندگان
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