来自阿斯加德古生物的小GTPase,路障和TRAPPC3蛋白质的真核生物样特征
Linh T Tran1, Caner Akıl1,2, Yosuke Senju1
1Research Institute for Interdisciplinary Science, Okayama University, Okayama, 700-8530, Japan.
Communications biology
|March 13, 2024
概括
在真核生物中调节膜结合区的关键蛋白质,如Rab GTPases,在真核生物起源之前就存在于它们最接近的原生生物亲属,阿斯加德古生物中.
科学领域:
- 进化生物学是进化的生物学.
- 细胞生物学 细胞生物学
- 结构生物学是结构生物学.
背景情况:
- 细胞是由被膜封闭的有机细胞定义的,这对于分离至关重要.
- 小GTPases及其调节器协调这些独特的细胞区的组装和维护.
- 诸如Rab GTPases,路障和长蛋白域蛋白质等蛋白质以及类似TRAPPC3的蛋白质是关键的调节者.
研究的目的:
- 为了调查真核细胞膜贩运机械的进化起源.
- 为了结构性地分析阿斯加德古生物中的蛋白质,这是最接近于真核生物的原核生物亲属.
- 了解参与真核细胞分离的蛋白质的祖先状态.
主要方法:
- 对阿斯加德古生物蛋白质进行比较结构分析.
- 评估GTPase核心域和蛋白质二分化.
- 检查路障,长蛋白和含有TRAPPC3域的蛋白质.
主要成果:
- 阿斯加德古生物的GTPase核心域与真核动物Rabs和Rags有很大的相似之处.
- 阿斯加德古生物中的含有路障,长蛋白和TRAPPC3域的蛋白质形成了类似于真核生物复合体的二元体.
- 基本的蛋白质结构早于真核生物的出现.
结论:
- 调节膜结合区的核心机制早于真核生成.
- 在真核生物进化之前,祖先的蛋白质架构存在于 prokaryotic 亲属中.
- 在早期的真核生物中,随后的适应是必要的,以调节不同的内部膜.
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