通过直接干扰Arp2/3活动,TmeB对抗了actin聚合
Kaylyn R Scanlon1, Gabrielle Keb2, Katerina Wolf2
1Division of Immunity and Pathogenesis, Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, United States.
Frontiers in cellular and infection microbiology
|July 24, 2023
概括
甲状腺炎感染涉及TmeA和TmeB的作用因子,它们在actin聚合过程中起到相反的作用. TmeA促进了入侵,而TmeB通过干扰Arp2/3复合体活动来抑制它.
科学领域:
- 微生物学 微生物学
- 细胞生物学 细胞生物学
- 病原体与宿主之间的相互作用
背景情况:
- 克拉米迪亚状炎虫在上皮细胞入侵中使用了III型分泌系统.
- 侵袭效应器TmeA和TmeB被一起编码,TmeA激活N-WASP进行actin聚合.
- 在入侵期间,TmeB的功能和TmeA和TmeB之间的相互作用仍然不清楚.
研究的目的:
- 为了功能性地描述TmeB,并阐明TmeA和TmeB在克拉米迪亚白虫入侵中的作用.
- 调查TmeB影响宿主细胞入侵的机制.
- 在actin聚合的背景下探索TmeA和TmeB的对立功能.
主要方法:
- 基因操纵Chlamydia trachomatis菌株以创建缺乏TmeA和TmeB的突变物.
- 使用各种突变菌株分析细菌入侵效率.
- 研究Arp2/3复合体在TmeB介导的侵入抑制中的作用.
- 生物化学测试,以评估TmeB对乙烯酸聚合物的影响.
主要成果:
- 当TmeB缺席时,TmeA可以用于入侵.
- 过多的TmeB抑制了克拉米迪亚虫的入侵,需要一个活跃的Arp2/3复合体.
- TmeB直接干扰Arp2/3介导的活性蛋白聚合.
结论:
- 在Chlamydia trachomatis入侵期间,TmeA和TmeB具有相反的功能.
- TmeB通过破坏Arp2/3-依赖的活性蛋白聚合而起到入侵的抑制作用.
- 这些发现揭示了一种复杂的调节机制,涉及TmeA,TmeB和细菌进入过程中的actin动态.
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