Resnick M A, Nilsson-Tillgren T
Yeast Genetics/Molecular Biology Group, National, Institute Environmental Health Sciences, Research Triangle Park, NC 27709.
Prog Clin Biol Res. 1990;340B:363-9.
Recombination is required for the repair of many types of lesions and it can be a source of genetic diversity. We are investigating the requirements for homology in recombination and the consequences of recombination between DNA divergent sequences. Recombination between sequences of partial homology could account for chromosome rearrangements leading to the generation of novel genes and possibly involved in initiating events in carcinogenesis. We have developed a method for examining the role of homology between a specific pair of chromosomes in "protecting" chromosomes against DNA damage (Resnick et al., 1989). In the yeast Saccharomyces cerevisiae DNA double-strand breaks (DSBs) induced in diploid G-1 cells are normally repaired by recombination between homologous chromosomes. When homology is greatly reduced the DSBs lead to chromosome loss. These observations suggest that the system that has been used to study the role of recombination in repair can also be used to measure double-strand damage at low biologically meaningful doses.
许多类型的损伤修复都需要重组，而且重组可能是遗传多样性的一个来源。我们正在研究重组中对同源性的要求以及DNA分歧序列之间重组的后果。部分同源序列之间的重组可能导致染色体重排，从而产生新基因，并可能参与致癌作用的起始事件。我们已经开发出一种方法，用于检测特定染色体对之间的同源性在“保护”染色体免受DNA损伤方面的作用（雷斯尼克等人，1989年）。在酿酒酵母中，二倍体G-1细胞中诱导产生的DNA双链断裂（DSB）通常通过同源染色体之间的重组来修复。当同源性大大降低时，DSB会导致染色体丢失。这些观察结果表明，用于研究重组在修复中作用的系统也可用于在低生物学意义剂量下测量双链损伤。
