کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1980915 1061888 2010 11 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
RecA protein assures fidelity of DNA repair and genome stability in Deinococcus radiodurans
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی زیست شیمی
پیش نمایش صفحه اول مقاله
RecA protein assures fidelity of DNA repair and genome stability in Deinococcus radiodurans
چکیده انگلیسی

Deinococcus radiodurans is one of the most radiation-resistant organisms known. It can repair hundreds of radiation-induced double-strand DNA breaks without loss of viability. Genome reassembly in heavily irradiated D. radiodurans is considered to be an error-free process since no genome rearrangements were detected after post-irradiation repair. Here, we describe for the first time conditions that frequently cause erroneous chromosomal assemblies. Gross chromosomal rearrangements have been detected in recA mutant cells that survived exposure to 5 kGy γ-radiation. The recA mutants are prone also to spontaneous DNA rearrangements during normal exponential growth. Some insertion sequences have been identified as dispersed genomic homology blocks that can mediate DNA rearrangements. Whereas the wild-type D. radiodurans appears to repair accurately its genome shattered by 5 kGy γ-radiation, extremely high γ-doses, e.g., 25 kGy, produce frequent genome rearrangements among survivors. Our results show that the RecA protein is quintessential for the fidelity of repair of both spontaneous and γ-radiation-induced DNA breaks and, consequently, for genome stability in D. radiodurans. The mechanisms of decreased genome stability in the absence of RecA are discussed.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: DNA Repair - Volume 9, Issue 11, 10 November 2010, Pages 1151–1161
نویسندگان
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