在D. melanogaster中,需要一个复杂的遗传基因位点,即多同源性,以进行细分特征和表皮发育
J M Dura1, N B Randsholt, J Deatrick
1Centre de Génétique Moleculaire, Centre National de la Recherche Scientifique, Gif-sur-Yvette, France.
Cell
|December 4, 1987
概括
多同类 (ph) 基因需要两个突变才能产生零效应,这表明复杂性. DNA分析揭示了对于ph基因功能至关重要的重复序列,这表明了新的遗传机制.
科学领域:
- 发育生物学是发展生物学.
- 遗传学 是一个遗传学.
- 分子生物学分子生物学
背景情况:
- 多同源性 (ph) 基因对胚胎发育至关重要.
- 在pH的零突变导致胚胎致死性和特定的表皮衍生物的损失.
- 单一事件突变表现出主要的功能获取表型,类似于已知的发育基因.
研究的目的:
- 为了研究多同源 (ph) 位点的遗传复杂性.
- 了解ph基因功能的分子基础及其不寻常的突变要求.
- 提出一个模型,用于phlocus的功能组织.
主要方法:
- 通过染色体步行进行定位克隆,以定位ph基因.
- 对由DNA重组引起的ph突变进行分析.
- 杂交研究以确定PH区域中重复的DNA元素.
主要成果:
- 使用缺陷和重新排列诱导的突变将ph基因局部化.
- 在ph locus.内确定了两个大,重复的DNA序列.
- 任何重复序列中的病变都会破坏ph基因功能,这证实了它们的重要性.
结论:
- 多同类 (ph) 基因位是遗传复杂的,需要两种突变性事件才能产生零表型.
- 复制序列的存在对于正常的ph基因功能至关重要.
- 提出了一个模型来解释ph locus. 的不同寻常的功能组织和遗传要求.
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