侧面序列的同转换与同质切换的同转换.
C McGill1, B Shafer, J Strathern
1Laboratory of Eukaryotic Gene Expression, National Cancer Institute, Frederick Cancer Research Facility, Maryland 21701.
Cell
|May 5, 1989
概括
在S. cerevisiae中,同位素切换取代了配对类型的DNA. 观察到可变的替换程度和共同转换梯度,这表明在交配类型切换过程中存在DNA异重复中间体.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 酵母生物学的酵母生物学
背景情况:
- 在Saccharomyces cerevisiae中,同位素切换是一种交配类型基因转换的过程.
- 交配类型位点 (MAT) 与静音位点 (HML或HMR) 交换DNA.
研究的目的:
- 为了研究在同位素切换过程中DNA替代程度的变化.
- 分析在MAT位置的X区域的共转换梯度.
- 探索侧边位点差异对DNA修复机制的影响.
主要方法:
- 使用限制位多态来区分MAT和供体位点.
- 在匹配类型切换过程中分析DNA序列替换模式.
- 检查相对于HO基因产品介导的双链裂变的共同转化事件.
主要成果:
- 在同位素切换过程中证明了MAT DNA替代的可变程度.
- 在X区域中确定了共转换的梯度.
- 在双链断裂的两侧观察到共转换.
- 在子细胞中发现不同的侧面部位,表明异双体中间体.
结论:
- 在S. cerevisiae交配类型切换过程中DNA替换的程度不是固定的.
- 一种DNA异重复中间体很可能参与共转化过程.
- 了解这些机制为基因转换和DNA修复途径提供了洞察力.
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