Response of EDAG knockout mice to low-dose radiation-induced damage / 军事医学

Objective To generate the erythroid differentiation associated gene(EDAG) knockout mice and analyze their sensitivity to low dose radiation-induced damage.Methods Zinc finger nuclease technology ( ZFNs ) was used to produce the EDAG knockout mice.The low dose radiation-induced damage was evaluated by peripheral blood cell counts, DNA damage and colony formation of bone marrow cells.Wild-type and EDAG knockout mice were irradiated with 0.31 Gy/min X-ray, one minute per day for seven consecutive days, and the cumulative radiation dose was 2.17 Gy(n=7).The blood cell counts were measured by an automated hemocytometer.DNA damage was detected by immunofluorescence assay with a DNA damage marker p-H2A.x antibody (n=3).The colony formation ability of bone marrow cells was evaluated with a semi-solid culture medium(n=3).Results A model of EDAG knockout mice was established.Compared to wide type mice, white blood cell counts of EDAG knockout mice decreased significantly while the DNA damage marker p-H2A.x expression was increased on the third day after X-ray irradiation.The ability of colony-forming was reduced after 7 days of X-ray irradiation.Conclusion Our present study found that EDAG knockout mice are more sensitive to low dose radiation-induced damage as shown by decreased peripheral blood cells counts, reduced colony-forming ability of bone marrow cells, and increased DNA damage.These results suggest that EDAG knockout mice can serve as a powerful tool for evaluation of the biological effects of low-dose radiation damage.

Construction of a GFP/Puro double-labeled lentiviral vector containing CK8 interfering RNA and its effect on cell apoptosis in vitro / 南方医科大学学报

<p><b>OBJECTIVE</b>To construct a GFP/Puro double-labeled lentiviral expression vector for CK8 silencing and assess the effects of CK8 silencing on cell apoptosis.</p><p><b>METHODS</b>The siRNA sequences of CK8 were inserted into the lentiviral expression vector GV248 and transfected into 293T cells with the packaging plasmids PMD and SPA. The lentivirus was collected at 24 and 36 h post-transfection. Flow cytometry was used to detect the virus titer and the positive cells were selected with puromycin. The knockdown of CK8 was examined by Western blotting. The effect of CK8 down-regulation on cell apoptosis induced by cisplatin was detected with Annexin V/PI staining.</p><p><b>RESULTS AND CONCLUSION</b>We successfully constructed CK8 interference lentiviral vector and obtained a stable cell line with CK8 knock-down that was sensitive to cisplatin-induced apoptosis.</p>