Department of Biomedical Engineering, Yale University, 55 Prospect Street, New Haven, Connecticut 06511, USA.
Systems Biology Institute, Yale University, 850 West Campus Drive, West Haven, Connecticut 06516, USA.
Phys Rev Lett. 2022 Jan 28;128(4):048103. doi: 10.1103/PhysRevLett.128.048103.
We explore the relationship between the nonequilibrium generation of myosin-induced active stress within the F-actin cytoskeleton and the pressure-volume relationship of cellular aggregates as models of simple tissues. We find that due to active stress, aggregate surface tension depends upon its size. As a result, both pressure and cell number density depend on size and violate equilibrium assumptions. However, the relationship between them resembles an equilibrium equation of state with an effective temperature. This suggests that bulk and surface properties of aggregates balance to yield a constant average work performed by each cell on their environment in regulating tissue size. These results describe basic physical principles that govern the size of cell aggregates.
我们探索了肌球蛋白在 F-肌动蛋白细胞骨架中产生的非平衡活性应力与细胞聚集体的压力-体积关系之间的关系，这些聚集体模型是简单组织的代表。我们发现，由于活性应力的存在，聚集体的表面张力取决于其大小。因此，压力和细胞数密度都取决于大小，且违反了平衡假设。然而，它们之间的关系类似于具有有效温度的平衡状态方程。这表明，聚集体的体相和表面性质达到平衡，使得每个细胞在调节组织大小时对环境做功的平均值保持恒定。这些结果描述了控制细胞聚集体大小的基本物理原理。
