长时间的第二阶段停止削弱了小鼠卵细胞中Aurora B/C-依赖的错误校正
Antoine Langeoire1, Alison Kem-Seng2, Damien Cladière1
1Université Paris Cité, CNRS, Institut Jacques Monod, 15 rue Hélène Brion, 75013 Paris, France; Sorbonne Université, Institut de Biologie Paris Seine, 9 quai St. Bernard, 75252 Paris, France; CNRS UMR7622, Developmental Biology Lab, Sorbonne Université, 9 quai St. Bernard, 75252 Paris, France.
Current biology : CB
|April 11, 2025
概括
哺乳动物卵子细胞可以错误分离染色体在二次变异期间由于染色体附着的错误. 长时间的停滞会损害错误纠正机制,导致持续的错误和潜在的形积分.
科学领域:
- 细胞生物学 细胞生物学
- 遗传学 遗传学 是一个
- 生殖生物学 生殖生物学
背景情况:
- 染色体分离错误是哺乳动物卵细胞在半位变化过程中常见的.
- 轴组合检查点 (SAC) 和错误校正机制对于精确的染色体分离至关重要.
- 关于二次变异过程中的这些机制的知识是有限的,特别是关于长期的二次变异停滞的知识.
研究的目的:
- 调查光B/C依赖的错误校正在检测和纠正低间基内托科尔张力在变质过程中的功能II.
- 为了确定长时间的二代相停止是否会影响卵细胞纠正染色体错位的能力.
主要方法:
- 使用低剂量的STLC (monastrol) 诱导在II代相早期的低基内托合体间张力.
- 监测SAC激活和亚纳相II进展,以应对诱导的低压.
- 在长期的第二阶段转基因停止期间,评估了Aurora B/C激酶活性和PP2A积累在kinetochores.
主要成果:
- 在早期的基因相II中,低的基因相间紧张激活了Aurora B/C,导致微管脱离,并通过SAC激活延迟基因相II.
- 在长期的第二阶段停滞期间,由于PP2A在kinetochore的积累,Aurora B/C活动不足以纠正低张力附着.
- 因此,SAC不会被激活,姐妹染色体会立即分离,即使有错误的连接.
结论:
- 哺乳动物卵细胞在早期的半位变化II中对染色体错误的错误纠正机制.
- 长时间的二代相停止会影响这种错误纠正,使卵细胞无法区分正确的和不正确的附着.
- 停产期间的这种损伤可能会导致持续的染色体分离错误和等待受精的卵子细胞的无倍积分.
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