佩克塞尔是出口和非出口等等菌蛋白质的蛋白质分解成熟场所
bioRxiv : the preprint server for biology
|July 28, 2023
概括
疟疾寄生虫使用PEXEL图案出口蛋白质,但这项研究发现,非出口蛋白质也经过PEXEL加工. 具体的残留物,而不是PEXEL裂纹,决定了蛋白质出口.
科学领域:
- 分子寄生虫学 分子寄生虫学
- 细胞生物学 细胞生物学
- 贩卖蛋白质 贩卖蛋白质 是一个问题.
背景情况:
- 疟疾寄生虫通过出口的效应蛋白来重塑宿主红细胞.
- 大多数出口的蛋白质使用PEXEL/宿主准基因进行Plasmepsin V (PMV) 的处理.
- PEXEL处理暴露了一个成熟的N端,这对于宿主细胞转移至关重要.
研究的目的:
- 调查非出口疟疾寄生虫蛋白中的PEXEL图案处理.
- 确定特定PEXEL残留物在蛋白质出口中的作用.
- 探索Plasmepsin V (PMV) 在蛋白质成熟中的更广泛的功能.
主要方法:
- 对非出口蛋白UIS2及其PEXEL图案的分析.
- 化学报告员合并以评估蛋白质出口.
- 在UIS2.2中PEXEL基因的位点定向突变发生.
主要成果:
- 非出口的蛋白质UIS2包含一个由PMV处理的PEXEL图案.
- 在UIS2 PEXEL的P1'位置上有一种特定的酸残留物,尽管允许PMV加工,但却取消了出口.
- 将这种残留物转化为氨酸使出口成为可能,确认N端特征决定出口.
- 其他非出口的禽蛋白质中的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.
- 成熟的N端内特定的残留物,而不是PEXEL裂纹本身,决定了蛋白质出口.
- 在疟疾寄生虫和相关物种中,PMV可能起到一般分泌成熟酶的作用.
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