在oomycete效应器中对RXLR和EER动图进行蛋白质分解处理
Lin Xu1, Shumei Wang1, Wei Wang1
1Division of Plant Sciences, School of Life Sciences, University of Dundee, at James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK.
The New phytologist
|September 27, 2024
概括
在分泌之前,OomyceteArg-任何氨基酸-Leu-Arg (RXLR) 和Glu-Glu-Arg (EER) 效应器都经过蛋白质分解处理,这是抑制植物免疫力的关键步骤. 这种处理对于效应器功能至关重要,但在宿主植物细胞中并不总是发生.
科学领域:
- 分子植物病原体相互作用
- 卵菌生物生物学 卵菌生物生物学
- 蛋白质生物化学 蛋白质生物化学
背景情况:
- 虫病原体利用效应蛋白来抑制宿主植物的免疫力.
- 任何氨基酸-Leu-Arg (RXLR) 和Glu-Glu-Arg (EER) 动机对效应器的功能和传递至关重要.
- 这些效应因子的翻译后处理在很大程度上仍然没有特征.
研究的目的:
- 为了研究RXLR和EER动机在Phytophthora感染者的蛋白质分解处理.
- 为了确定RXLR和EER图案切割的时间和位置.
- 了解处理对效应器功能和分泌的影响.
主要方法:
- 使用了分子,细胞和生物化学技术的组合.
- 在体外和宿主植物细胞 (Nicotiana benthamiana) 中分析了效应器加工.
- 通过使用特定的效应器构造,研究了RXLR和EER图案中的裂纹点.
主要成果:
- 在RXLR基因的蛋白质分解裂变始终发生在分泌前.
- 独立地也观察到EER图案的裂变,发生在氨酸残留物后.
- 在Nicotiana benthamiana表达的效应体显示处理不良,表明裂变取决于细胞类型.
结论:
- RXLR和EER动机的蛋白质分解处理是Phytophthora infestans作用因子的一般预分泌事件.
- RXLR图案的位置约束表明它们是针对特定的,可能是混乱的区域.
- 预分泌处理对效应器功能至关重要,在宿主植物细胞中,裂变不会有效地发生.
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