Cytological Monitoring of Meiotic Crossovers in Spermatocytes and Oocytes
Cytological Monitoring of Meiotic Crossovers in Spermatocytes and Oocytes
复制标题
精母细胞和卵母细胞减数分裂交叉的细胞学监测
DOI：
10.1007/978-1-0716-0644-5_19
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发表时间：
2020
影响因子：
--
通讯作者：
Hunter Neil
中科院分区：
文献类型：
--
作者：
Yun Yan;Ito Masaru;Sandhu Sumit;Hunter Neil
同源染色体间的交换是减数分裂后期染色体分离的关键。有缺陷的交换与不孕、妊娠流产和先天性疾病有关。本章介绍了在细胞学水平上分析小鼠精母细胞和卵母细胞减数分裂交换的优化方案。第一种方法采用免疫细胞学来检测MLH 1，MLH 1是一种DNA错配修复蛋白，其特异性地标记减数分裂原蛋白-I的粗线期阶段的交叉位点。这些免疫细胞学方法对于其他重组步骤的分析具有通用性，例如起始和DNA链交换。第二种方法使交叉可视化，交叉是终变期和中期I阶段同源染色体之间的物理交换点。这两种方法都很容易适用于其他脊椎动物物种的交叉分析。
Crossing-over between homologous chromosomes is essential for accurate chromosome segregation at anaphase-I of meiosis. Defective crossing-over is associated with infertility, pregnancy miscarriage, and congenital disease. This chapter presents optimized protocols for the analysis of meiotic crossovers at the cytological level in spermatocytes and oocytes from mouse. The first approach employs immunocytology to detect MLH1, a DNA mismatch-repair protein that specifically marks crossover sites in the pachytene stage of meiotic prophase-I. These immunocytological methods have general utility for the analysis of other recombination steps, such as initiation and DNA strand exchange. The second approach visualizes chiasmata, the points of physical exchange between homologous chromosomes that are present during the diakinesis and metaphase-I stages. Both approaches are readily adaptable to the analysis of crossing over in other vertebrate species.