National Yang-Ming University, Institute of Biophotonics, Taipei 11221, Taiwan.
J Biomed Opt. 2014 Jan;19(1):011008. doi: 10.1117/1.JBO.19.1.011008.
Cell division plays an important role in regulating cell proliferation and differentiation. It is managed by a complex sequence of cytoskeleton alteration that induces dividing cells to change their morphology to facilitate their division. The change in cytoskeleton structure is expected to affect the intracellular viscoelasticity, which may also contribute to cellular dynamic deformation during cell division. However, the intracellular viscoelasticity during cell division is not yet well understood. In this study, we injected 100-nm (diameter) carboxylated polystyrene beads into the cytoplasm of HeLa cells and applied video particle tracking microrheology to measure their intracellular viscoelasticity at different phases during cell division. The Brownian motion of the intracellular nanoprobes was analyzed to compute the viscoelasticity of HeLa cells in terms of the elastic modulus and viscous modulus as a function of frequency. Our experimental results indicate that during the course of cell division, both intracellular elasticity and viscosity increase in the transition from the metaphase to the anaphase, plausibly due to the remodeling of cytoskeleton and redistributions of molecular motors, but remain approximately the same from the anaphase to the telophase.
细胞分裂在调节细胞增殖和分化方面起着重要作用。它由一系列复杂的细胞骨架改变来管理，这些改变促使分裂细胞改变形态以促进其分裂。细胞骨架结构的变化预计会影响细胞内的粘弹性，这也可能有助于细胞在细胞分裂过程中的动态变形。然而，细胞分裂期间的细胞内粘弹性尚不清楚。在这项研究中，我们将 100nm（直径）的羧基化聚苯乙烯珠注入 HeLa 细胞的细胞质中，并应用视频粒子跟踪微流变学测量细胞内粘弹性在细胞分裂不同阶段的变化。分析细胞内纳米探针的布朗运动，以计算 HeLa 细胞的粘弹性，即弹性模量和粘性模量随频率的变化。我们的实验结果表明，在细胞分裂过程中，从中期到后期，细胞内的弹性和粘性都增加，这可能是由于细胞骨架的重塑和分子马达的重新分布，但从后期到末期基本保持不变。
