在纤维环境中被困,定位和定向了线粒状
Apurba Sarkar1, Aniket Jana2, Atharva Agashe2
1School of Mathematical and Computational Sciences, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India.
PNAS nexus
|July 9, 2025
概括
细胞被细胞外基质 (ECM) 封闭,影响了线粒分裂. 动蛋白收缩纤维 (RFs) 根据限制进行组织,在细胞分裂过程中驱动元相板 (MP) 旋转和倾斜.
科学领域:
- 细胞生物学 细胞生物学
- 生物物理学的生物物理.
- 细胞外矩阵生物学 细胞外矩阵生物学
背景情况:
- 精确的线粒轴定位对于细胞健康至关重要.
- 细胞外矩阵 (ECM) 的限制可以破坏轴方向和元相板 (MP) 的对齐.
- 了解物理限制如何影响线粒分裂对于理解细胞过程至关重要.
研究的目的:
- 调查不同程度的ECM限制对线粒细胞机理和螺旋定位的影响.
- 阐明行动蛋白收缩纤维 (RFs) 在调解受限对线粒分裂的影响中的作用.
- 开发一种机械模型,预测在不同的限制条件下转相板 (MP) 的倾斜.
主要方法:
- 利用灵活的,模仿ECM的纳米纤维来控制细胞封闭水平.
- 观察并分析了细胞皮层上的三维组织的行动素收缩纤维 (RFs).
- 采用随机蒙特卡洛模拟来模拟细胞分裂动态,包括RF,中心体和染色体.
主要成果:
- 封闭级别决定了RF的3D组织成三角形和带状图案.
- 细胞皮层上的射频模式被确定为MP旋转的关键驱动因素.
- 模拟准确地复制了MP在不同限制下倾斜的实验观测.
- 高ECM限制可以诱导局部皮质变形,影响MP倾斜.
- 皮层变形和RF集体限制MP倾斜,而不对称的MP定位增加倾斜.
结论:
- 由于改变了RF组织和皮质力学,ECM的限制显著影响了线粒状的方向.
- 射频,皮层变形和MP位置之间的相互作用决定了MP倾斜的程度.
- 这些发现为在体内发现的狭窄微环境中的线粒分裂提供了基本的见解.
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