一个由两个组成部分组成的调节系统调解了古老时代Haloferax volcanii中的依赖于定数感应的形态和运动过渡
Jacob A Cote1, Priyanka Chatterjee1, Marco Garcia2
1Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104.
bioRxiv : the preprint server for biology
|November 26, 2025
概括
我们在Haloferax volcanii. archaeon中发现了一个新的定数感应 (QS) 监管系统,QarABC. 这个系统控制着运动棒和非运动盘之间的过渡,揭示了古生物中的新 QS 机制.
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:
- 基数感应 (QS) 调节基于人口密度的微生物集体行为.
- 人们对古生物学中的QS机制的了解很少,这限制了我们对微生物生态和进化的了解.
- 在响应盘形成信号 (DFS) 的情况下,Haloferax volcanii表现出从运动棒到非运动盘的密度依赖的过渡.
研究的目的:
- 确定Haloferax volcanii中DFS监管网络的遗传组成部分.
- 阐明已识别的基因在古人类的群体感知和细胞分化中的作用.
- 描述第一个涉及古物质中QS依赖行为的双组件系统 (TCS).
主要方法:
- 在含有DFS的介质中选自发运动性突变.
- 基因删除和候选基因的突变分析 (HVO_1357,HVO_1356,HVO_1358).
- 突变菌株的表型分析,包括运动性检测和显微镜检测.
- 转录组分析以评估基因表达变化.
主要成果:
- 鉴定并将三个基因命名为 qarABC,编码一种新的 TCS.
- 删除 qarA 导致构成性运动性和对 DFS 的敏感性降低.
- 删除qrB或qrC导致非运动性和过早的磁盘形成.
- 在qarA中抑制器突变恢复了 ΔqarB 和 ΔqarC 突变的运动性,表明 QarA 是中央调节者.
- qarA删除高调调节了与运动性和棒形形成相关的基因.
结论:
- 卡尔ABC基因形成了一个对DFS反应的调节模块,控制Haloferax volcanii中的QS依赖细胞分化.
- 这项研究揭示了第一个在古生物中的TCS被证明可以调节QS依赖的行为.
- 这些发现显著提升了我们对古 QS 机制和微生物社会行为的理解.
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