佩克塞尔是出口和非出口的等蛋白质的蛋白质分解成熟场所
Manuel A Fierro1, Ajla Muheljic2, Jihui Sha3
1Department of Biomedical Sciences, Iowa State University, Ames, lowa, USA.
mSphere
|February 9, 2024
概括
疟疾寄生虫使用出口的蛋白质重塑宿主细胞,通常通过Pexel图案通过Plasmepsin V (PMV) 处理. 这项研究显示,非出口蛋白质也含有PMV处理的PEXEL,其特定的残留物阻止出口.
科学领域:
- 细胞生物学 细胞生物学
- 寄生虫学的寄生虫学
- 分子生物学分子生物学
背景情况:
- 强制性细胞内疟疾寄生虫为了生存而重塑宿主红细胞.
- 蛋白质出口对寄生虫的生存和病变产生至关重要.
- 米出口元素 (PEXEL) 图案由Plasmepsin V (PMV) 处理,用于蛋白质出口.
研究的目的:
- 调查非出口疟疾寄生虫蛋白中的PEXEL图案处理.
- 确定决定蛋白质出口与非出口的因素.
- 探索PMV在蛋白质成熟中的更广泛作用.
主要方法:
- 对非出口蛋白UIS2及其PEXEL图案的分析.
- 化学记者融合以测试蛋白质转位.
- 在PEXEL残留物的位点定向突变发生.
- 对其他非出口的类动物蛋白质进行比较分析.
主要成果:
- 非出口的蛋白质UIS2含有由PMV.处理的PEXEL图案.
- 在UIS2 PEXEL中的特定残留物,尽管经过PMV加工,但废除了出口.
- 单个残留物的突变使出口成为可能,证实了N-终端决定因素.
- 其他非出口蛋白质中的PEXEL图案也由PMV加工.
结论:
- 在PMV的PEXEL加工中,不仅仅是出口的蛋白质.
- 特定的N端特征,而不仅仅是PEXEL裂纹,决定了出口.
- 在疟疾寄生虫中,PMV充当一般分泌成熟酶.
- 这项研究为Plasmodium falciparum中蛋白质出口管制提供了新的见解.
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