在含有两个水相的巨型囊泡中,芽生长和不对称的蛋白质微分区
M Scott Long1, Ann-Sofie Cans, Christine D Keating
1Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
Journal of the American Chemical Society
|December 21, 2007
概括
外部度控制微分区和巨型脂质囊泡中的芽,具有水性双相系统 (ATPS GVs). 增加的度增强了蛋白质的丰富性,并诱导了细胞的极性,为原始细胞模型提供了洞察力.
科学领域:
- 细胞生物学 细胞生物学
- 生物物理学的生物物理.
- 生物化学 生物化学
背景情况:
- 具有水性双相系统 (ATPS) 的巨型脂质囊泡 (GVs) 模拟了细胞质的拥挤环境.
- ATPS在GV中创建了独特的微环境,允许局部蛋白质度差异.
研究的目的:
- 为了研究外部度对ATPS GVs的影响.
- 了解度如何影响生物分子微分区和细胞极性.
主要方法:
- 含有聚乙烯基醇 (PEG) 和德克斯ATPS的巨型脂质囊泡暴露于不同的外部度.
- 用显微镜和度测量量蛋白质丰富和芽事件的量化.
主要成果:
- 从100到200mmol/kg增加外部度,在富含德克斯的阶段增强了大豆聚氨酸的丰富度,从2.3倍增加到10倍.
- 超性条件诱导了囊泡的芽,导致结构和内部蛋白质分布不对称 (极性).
- 芽频率随着离子强度的增加而增加,并且通过降低度可逆.
结论:
- 外部度是调节微分区并诱导ATPS GV中极性的关键因素.
- 透收缩诱导的对称性破坏为研究原始细胞中的生化不对称性提供了一个模型.
- ATPS GV 提供了一个有价值的实验系统,用于在单细胞水平上探索细胞极性机制.
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