Department of Physics and BioInspired Syracuse, Syracuse University, Syracuse, New York 13244, USA.
Institute for Medical Engineering and Science and Department of Physics, MIT, Cambridge, Massachusetts 02139, USA.
Phys Rev Lett. 2021 Apr 16;126(15):158101. doi: 10.1103/PhysRevLett.126.158101.
The cell nucleus houses the chromosomes, which are linked to a soft shell of lamin protein filaments. Experiments indicate that correlated chromosome dynamics and nuclear shape fluctuations arise from motor activity. To identify the physical mechanisms, we develop a model of an active, cross-linked Rouse chain bound to a polymeric shell. System-sized correlated motions occur but require both motor activity and cross-links. Contractile motors, in particular, enhance chromosome dynamics by driving anomalous density fluctuations. Nuclear shape fluctuations depend on motor strength, cross-linking, and chromosome-lamina binding. Therefore, complex chromosome dynamics and nuclear shape emerge from a minimal, active chromosome-lamina system.
细胞核内包含染色体，染色体与 lamin 蛋白丝的软壳相连。实验表明，相关的染色体动力学和核形状波动源于马达活动。为了确定物理机制，我们开发了一个与聚合物壳结合的活性交联 Rouse 链的模型。系统大小的相关运动确实发生了，但需要马达活动和交联。收缩马达尤其通过驱动异常密度波动来增强染色体动力学。核形状波动取决于马达强度、交联和染色体-层粘连蛋白结合。因此，复杂的染色体动力学和核形状源于最小的活性染色体-层粘连蛋白系统。
