涉及pilin结构基因的基因转换与pilus+相关,与Neisseria gonorrhoeae中的pilus-变化保持平衡
Cell
|October 24, 1986
概括
尼塞利亚淋病经历了快速的皮卢斯阶段变化. 这项研究揭示了从皮林表达到非表达状态的可逆过渡涉及皮林结构基因内的内基因重组和基因转换.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
背景情况:
- 尼塞利亚淋病 (Gc) 经常在表达 (pilus+) 和不表达 (pilus-) 状态之间切换.
- 只有pilus-Gc的一个子集才能恢复pilus+表型,这表明可逆性的特定机制.
研究的目的:
- 研究pilus+Gc与特定的pilus-变体 (P-rp+表型) 之间的可逆相变的基础分子机制.
- 阐明内基因重组和基因转换在皮卢斯相变异中的作用.
主要方法:
- 在具有独特的"组装误解"突变的pilus变体 (P-rp+) 中分析pilin mRNA和聚.
- 检查参与pilus+和P-rp+表型之间过渡的DNA序列.
主要成果:
- 在Gc中可逆的皮勒斯相过渡可以通过内基因重组驱动.
- 同源DNA序列的非相互交换发生在一个沉默的,存储的部分pilin基因和表达的pilin基因位点之间.
- 这一过程导致pilus+表型的恢复.
结论:
- 炎球菌的pilus阶段变异,类似于pilus抗原变异,可以通过基因转换在pilin结构基因表达位发生.
- 这些发现为Neisseria gonorrhoeae中pilus表达的可逆性提供了分子解释.
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