细胞脂肪化驱动了血的向,并增强了来自Pseudomonas syringae的几种III型效应蛋白的功能
Z Nimchuk1, E Marois, S Kjemtrup
1Department of Biology, University of North Carolina at Chapel Hill, 27599, USA.
Cell
|June 1, 2000
概括
细菌的III型因子,包括激发蛋白 (Avr) 蛋白,针对宿主血进行功能. 这些细菌蛋白质使用宿主基化,一种特定于真核生物的修饰,以有效地定位和毒性.
科学领域:
- 微生物学 微生物学
- 植物病理学 植物病理学
- 分子生物学分子生物学
背景情况:
- 细菌病原体使用III型分泌系统 (T3SS) 输送效应蛋白到宿主细胞中.
- 植物免疫系统通过疾病耐药性 (R) 基因识别一些T3SS效应体 (avirulence蛋白,Avr).
- 在敏感 (r) 植物中,AVR蛋白可以增强病原体的毒性.
研究的目的:
- 研究细菌III型因子体的亚细胞定位和功能要求.
- 为了确定细菌效应器是否利用宿主特定的翻译后修饰来实现功能.
主要方法:
- 在宿主细胞中对Pseudomonas syringae型III效应物的局部化研究.
- 分析myristoylation共识点及其在效应器定位中的作用.
- 在活体中对AVR蛋白质进行里斯托化试验.
主要成果:
- 一些T3SS效应器,包括Avr蛋白,是针对宿主血的.
- 有效的膜联结增强了效应器的功能.
- 三种Avr蛋白质的血局部化需要密度化位.
- 在宿主细胞内,AVR蛋白经历基化.
结论:
- Prokaryotic III 类型的效应器利用真核生物特定的翻译后修饰,如 myristoylation,以访问特定的亚细胞区.
- 基化促进了细菌AVR蛋白的等离子膜向,增强了它们的功能,并可能导致病原体的毒性.
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