一种分泌的内生生体蛋白质,对于殖民宿主细胞至关重要
bioRxiv : the preprint server for biology
|December 15, 2025
概括
一种新发现的Buchnera蛋白质SyeA对于有义务的虫内生体进入宿主细胞并逃避免疫破坏至关重要,揭示了细菌共生进化的洞察力.
科学领域:
- 微生物学 微生物学
- 进化生物学 进化生物学
- 细胞生物学 细胞生物学
背景情况:
- 细胞内细菌共生在真核生物中很常见,特别是在昆虫中,虫中的Buchnera是研究得很好的例子.
- 虽然Buchnera基因组提供了关于起源和新陈代谢的见解,但宿主细胞进入和免疫抑制的机制仍然不清楚.
- 了解这些机制对于理解互惠的内共生态的演变和维持至关重要.
研究的目的:
- 为了识别和描述参与布奇纳内共生体与宿主相互作用的新型蛋白质.
- 阐明这些蛋白质在宿主细胞进入,免疫逃避和传播中的作用.
- 为了调查布克内拉细胞内生活方式的进化起源.
主要方法:
- 生物信息学分析以识别布赫内拉祖先分泌的蛋白质.
- 免疫光显微镜可视化蛋白质定位和宿主细胞动态.
- RNA干扰 (RNAi) 在体内评估已识别的蛋白质 (SyeA) 的功能.
- 在SyeA敲除后分析溶酶体活性和细菌存活率.
主要成果:
- 一种未经表征的Buchnera蛋白,SyeA,被确定为内共生体传播的关键.
- SyeA是分泌的,与细菌病原体作用因子相同,其水平在宿主细胞殖民期间达到峰值.
- 通过与宿主actin聚合机制 (Rho1) 相互作用,SyeA促进了Buchnera的进入,并防止了 lysosomal 降解.
- syeA的淘汰破坏了殖民,胚胎发育,并导致了Buchnera的破坏.
结论:
- SyeA是一种关键的效应蛋白,可以使Buchnera在宿主细胞内的细胞内存在.
- 这些发现表明SyeA是祖先致病性的遗留物,适应了相互共生.
- 这项研究为古老的内共生生物如何建立和维持细胞内关联提供了罕见的机械洞察力.
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