在S. cerevisiae中,在化过程中进行重组和突触膜复合体形成的时间比较
1Department of Biochemistry and Molecular Biology, Harvard University, Cambridge, Massachusetts 02138-2092.
Cell
|September 20, 1991
概括
双链断裂 (DSBs) 在突触膜复合体 (SC) 形成之前,在酵母中启动介质重组. 随着SCs的成熟,DSBs得到解决,这表明SC协调了重组事件.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 细胞生物学 细胞生物学
背景情况:
- 半月症涉及同源染色体配对和重组.
- 交叉膜复合体 (SC) 的形成是半半变化的关键事件.
- 双链断裂 (DSB) 对于启动介质重组至关重要.
研究的目的:
- 调查S. cerevisiae中DSB形成和SC组合之间的时间关系.
- 探索DSBs在SC形成和中介性进展中的作用.
- 讨论介质性重组的进化起源.
主要方法:
- 同步培养的S. cerevisiae经历了化.
- 在介质前期观察DSB形成和SC组合.
主要成果:
- DSBs发生在中介性预发期的早期,在SC形成之前.
- 在SC延长 (zygotene) 过程中,DSBs消失,并转化为其他中间体.
- 成熟的重组分子在SCs完全形成后出现 (pachytene).
结论:
- 形成DSB似乎是SC形成的先决条件.
- 总监会可以协调介质再组合中间体的成熟.
- 线性DSB修复途径可能是介质重组的进化前体.
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