重温酵母Atg1复合物的演化过程
Kha M Nguyen1, Hannah R Shariati1, Calvin K Yip1
1Life Sciences Institute, Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, Canada.
Autophagy reports
|October 2, 2025
概括
酵母Atg1复合体在芽和裂变酵母之间演变不同. 带有Atg101的起芽酵母显示了杆状的Atg17支架,这表明了与自相关的蛋白质的替代进化路径.
科学领域:
- 分子和细胞生物学分子和细胞生物学
- 进化生物学 进化生物学
- 酵母遗传学 酵母遗传学
背景情况:
- 与自相关的 (ATG) 蛋白质复合体,特别是Atg1,对于启动酵母中非选择性自至关重要.
- 在发芽酵母 (Saccharomyces cerevisiae) 和裂变酵母 (Schizosaccharomyces pombe) 之间存在不同的Atg1复合物的组成,具有不同的支架蛋白 (Atg17,Atg29,Atg31与Atg17,Atg101).
- 这些组成差异对Atg17的进化时间表和结构影响在很大程度上是未知的.
研究的目的:
- 为了研究酵母中Atg1复合物的进化分歧.
- 为了确定不同酵母菌种Atg17支架的结构变化.
- 探索Atg101整合和Atg13 HORMA域的潜在功能影响.
主要方法:
- 在各种酵母菌种中对Atg1复合物的系统成分分析.
- 结构建模和负染色电子显微镜 (EM) 用于支架结构的确定.
- 在Schizosaccharomyces pombe.中对Atg13 HORMA域的分析.
主要成果:
- 在几种发芽的酵母物种的Atg1复合体中发现了Atg101,其中一些与Atg29/Atg31同时发生.
- 具有Atg101的起芽酵母物种表现出棒形的Atg17支架,与缺乏Atg101的物种的S形支架形成鲜明对比.
- 在Schizosaccharomyces pombe中的Atg13 HORMA域可能有一个稳定帽,暗示Atg101.1.的独特作用.
结论:
- 芽酵母中Atg101的存在与棒状的Atg17结构相关,这表明了显著的进化转变.
- 这些发现表明Atg1复杂结构和功能在酵母菌谱系中的其他进化途径.
- 这项研究描绘了核心自启动复合体的潜在进化轨迹.
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