Research Paper Volume 10, Issue 6 pp 1454—1473

Naked mole rat cells display more efficient excision repair than mouse cells

Figure 6. The efficiency of DNA synthesis by extracts from NMR and mouse cells with different post-irradiation time. (A) The 100 nM 5'-[32P] 32-mer DNA with 5'-dRP-nick (odd lanes) or with 5'-pDEG-nick (even lanes) were incubated with 0.1 µM Polβ (lanes 3 and 4), 0.5 mg/ml of cell extract protein of NMR (lanes 5 – 14) or mouse (lanes 15 – 24) fibroblasts and buffer components. The reaction mixtures were incubated at 37ºC for 10 min. The control probes C1 and C2 contained only substrate DNAs and buffer components. The mixtures were supplemented with loading buffer, heated at 970C for 10 min, and the products were then analyzed as described in ‘DNA polymerase activity of cell extracts’. (B) Quantification of the DNA synthesis products for 5'-pDEG-nick DNA shown in A. White parts of bars correspond to non-elongated primer, grey parts reflect the amount of primer elongated by one dNMP and black parts correspond to the products of strand-displacement DNA synthesis. ‘n’ designates non-irradiated cells.