Heterochromatinization associated with cell differentiation as a model to study DNA double strand break induction and repair in the context of higher-order chromatin structure. | LitMetric
Cell differentiation is associated with extensive gene silencing, heterochromatinization and potentially decreasing need for repairing DNA double-strand breaks (DSBs). Differentiation stages of blood cells thus represent an excellent model to study DSB induction, repair and misrepair in the context of changing higher-order chromatin structure. We show that immature granulocytes form γH2AX and 53BP1 foci, contrary to the mature cells; however, these foci colocalize only rarely and DSB repair is inefficient. Moreover, specific chromatin structure of granulocytes probably influences DSB induction.
Center for Comparative Biomedicine, Ministry of Education Key Laboratory of Systems Biomedicine, State Key Laboratory of Medical Genomics, Institute of Systems Biomedicine, Shanghai Jiao Tong University, Shanghai 200240, China.
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