等离子膜折叠使成长中的哺乳动物细胞的表面积与体积比保持不变
Weida Wu1, Alice R Lam2, Kayla Suarez2
1Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Current biology : CB
|March 18, 2025
概括
哺乳动物细胞在生长时保持着惊人的恒定表面积与体积的比率,这要归功于膜折叠的增加. 这确保了足够的等离子膜面积,用于基本的细胞功能.
科学领域:
- 细胞生物学 细胞生物学
- 生物物理学的生物物理.
- 定量生物学 定量生物学
背景情况:
- 细胞面临着几何限制,特别是表面积与体积 (SA/V) 的比率,影响营养吸收和大小.
- 随着细胞大小的增加,SA/V比率的下降是一个常见的假设,类似于球体.
- 在哺乳动物细胞中研究SA/V缩放是复杂的,因为等离子体膜结构.
研究的目的:
- 在哺乳动物细胞中研究细胞表面成分与细胞大小的缩放.
- 为了确定SA/V比率是否保持不变或随着细胞大小的增加而减少.
- 了解使SA/V比率维持成为可能的机制.
主要方法:
- 单细胞测量细胞质量,血膜蛋白和脂质.
- 对细胞表面成分相对于细胞大小的缩放进行分析.
- 电子显微镜可用于可视化等离子体膜结构.
主要成果:
- 细胞表面成分在各种增殖细胞系中与细胞大小成比例缩放.
- 观察到几乎恒定的SA/V比率,独立于细胞周期阶段和静止细胞.
- 较大的细胞中血折叠的增加,包括多倍体细胞,保持了恒定的SA/V比率.
- 特定的蛋白质和胆固醇显示出与比例缩放的偏差.
结论:
- 哺乳动物细胞在各种尺寸中积极保持恒定的SA/V比率.
- 血折叠是维持细胞生长和多倍化过程中SA/V比率的关键机制.
- 恒定的SA/V比对支持细胞的重要过程至关重要,如分裂,营养摄取和变形.
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