Börner G V
Department of Biological, Geological and Environmental Sciences, Cleveland State University, 2121 Euclid Ave., Cleveland, OH 44115, USA.
Biochem Soc Trans. 2006 Aug;34(Pt 4):554-6. doi: 10.1042/BST0340554.
During meiosis, numerous DSBs (double-strand breaks) are induced along the genome which are processed via several steps into crossovers. Crossovers ensure the faithful segregation of homologous chromosomes during meiosis I. Although required for faithful chromosome segregation, DSBs pose a severe hazard to genome integrity. Chromosome segregation in the presence of persisting DSBs can result in loss or missegregation of entire chromosome arms and in the formation of aneuploid gametes, conditions frequently associated with birth defects, still births and cancer susceptibility in offspring. Co-ordination between chromosomal exchange and meiotic cell-cycle progression is achieved via a surveillance mechanism commonly referred to as the recombination checkpoint. Both components of the mitotic DNA damage checkpoint as well as meiosis-specific functions contribute to this highly conserved surveillance system.
在减数分裂过程中，基因组会诱导产生大量双链断裂（DSB），这些双链断裂会通过几个步骤被加工成交叉。交叉确保了减数分裂I期间同源染色体的忠实分离。虽然双链断裂是忠实染色体分离所必需的，但它们对基因组完整性构成了严重威胁。在存在持续双链断裂的情况下进行染色体分离，可能会导致整个染色体臂的丢失或错误分离，并形成非整倍体配子，这些情况常常与后代的出生缺陷、死产和癌症易感性相关。染色体交换与减数分裂细胞周期进程之间的协调是通过一种通常称为重组检查点的监测机制实现的。有丝分裂DNA损伤检查点的两个组成部分以及减数分裂特异性功能都对这个高度保守的监测系统有贡献。
