在Physarum polycephalum核rDNA中的一个移动组I内
1Section of Biochemistry, Molecular and Cell Biology, Cornell University, Ithaca, New York 14853.
Cell
|February 10, 1989
概括
在Physarum polycephalum中确定了一个移动的核内子. 这一组I内子 (intron 3) 通过基因转换转化为DNA,证明了核内子的移动性和内核酶活性.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 生物化学 生物化学
背景情况:
- 核内子通常是非移动的遗传元素.
- 组I内子的移动性主要在有机体中观察到.
研究的目的:
- 为了研究Physarum polycephalum.在特定的核群I内 (内3) 的移动性.
- 为了确定内部转移的机制,并识别任何编码的酶活性.
主要方法:
- 虫的交配来自内部缺乏和内部含有菌株.
- 对交配后的DNA序列进行分析,以观察内部集成.
- 克隆引子的体外转录和翻译以评估核酶活性.
主要成果:
- 在Amoebal交配后,Intron 3证明了对受体rDNA分子的特定位点转化.
- 基因转换的证据,包括接壤序列的共同转换和受体DNA中的双链断裂.
- 实验室研究证实,intron 3编码了一种酶活性,特定于位点的核酶.
结论:
- 核群I内子可以是移动的遗传元素.
- 通过自我编码的内核酶诱导的基因转换,发生了Intron 3转换.
- 这项研究提供了核内子转移的第一个实验证据,以及由RNA聚合酶I转录编码的蛋白质的罕见例子.
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