Note for: Nbs1 is essential for DNA repair by homologous recombination in higher vertebrate cells
Note for: Nbs1 is essential for DNA repair by homologous recombination in higher vertebrate cells (doi: 10.1038/nature01125) It has been proposed that Rad50-Mre11-Nbs1 cpx possesses nuclease activity to create 3' single stranded tails. Mre11-Rad50 are very conserved among yeast and human, except Xrs2 (homolog to Nbs1,Nijmegen breakage syndrome, in human also higher eukaryote). NBS1 -- part of the NRM cpx and responsible for ATP-driven DNA unwinding and nuclease activity. Mre1-null -- lethal in vertebrate cells, not yeast Rad50 null -- lethal in vertebrate cells, not yeast Nbs1 null is lethal in embryonic mice but not in DT40, therefore, we can study. Mitomycin C relies on HR-mediated post-replicational repair. NHEJ-end joining assay- 1. DT40 results in 29% microhomology 2. Ku70(-/-) - used 100% microhomology (lack of end-joining function) SCneo-reporter construct; 1. transiently transfected I-Sce I enzyme 2. DSB is introduced by I-S...