在Rhizobium meliloti中,nif基因表达的级联调节
M David1, M L Daveran, J Batut
1Laboratoire de Biologie Moléculaire des Relations Plantes-Microorganismes CNRS-INRA, BP27, Castanet-Tolosan, France.
Cell
|August 26, 1988
概括
研究人员在Rhizobium meliloti中发现了fixL和fixJ两种基因,这些基因调节固定 (nif和fix) 基因. 这些基因激活了一个调节级联,这对于共生性固化至关重要.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 固化对植物生长至关重要,并且依赖于像Rhizobium meliloti这样的共生细菌中的复杂基因调节.
- 了解控制固基因 (nif和fix) 的调节机制是优化共生关系的关键.
研究的目的:
- 为了识别和描述涉及Rhizobium meliloti固化的新型调节基因.
- 阐明控制共生性固基因表达的调节级联.
主要方法:
- 对Rhizobium meliloti进行遗传分析.
- 在不同氧气条件下的基因表达研究.
- 蛋白质家族的生物信息分析.
主要成果:
- 在Rhizobium meliloti发现了两个积极的调节基因,fixL和fixJ.
- 建立了一个调节级联,其中 fixL 和 fixJ 激活 nifA,然后激活 nifHDK 和 fixABCX.
- 通过fixL和fixJ介导,证明了fixN和nifA表达的依赖氧的调节.
结论:
- 在Rhizobium meliloti中,FixL和FixJ是共生固定基因表达的重要正调节剂.
- "FixL/FixJ"系统是一个由两个组成部分组成的监管系统,可检测环境线索,即可能的氧气水平.
- 这一发现提供了对 prokaryotes 中固化的复杂调节的洞察.
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