Acta Mechanica Sinica

, Volume 33, Issue 2, pp 222–233 | Cite as

Growing actin networks regulated by obstacle size and shape

  • Bo Gong
  • Ji Lin
  • Jin Qian
Research Paper


Growing actin networks provide the driving force for the motility of cells and intracellular pathogens. Based on the molecular-level processes of actin polymerization, branching, capping, and depolymerization, we have developed a modeling framework to simulate the stochastic and cooperative behaviors of growing actin networks in propelling obstacles, with an emphasis on the size and shape effects on work capacity and filament orientation in the growing process. Our results show that the characteristic size of obstacles changes the protrusion power per unit length, without influencing the orientation distribution of actin filaments in growing networks. In contrast, the geometry of obstacles has a profound effect on filament patterning, which influences the orientation of filaments differently when the drag coefficient of environment is small, intermediate, or large. We also discuss the role of various parameters, such as the aspect ratio of obstacles, branching rate, and capping rate, in affecting the protrusion power of network growth.


Actin network Growth dynamics Monte Carlo simulation Size effect Shape effect 



The project was supported by the National Natural Science Foundation of China (Grants 11321202, 11672268) and the Zhejiang Provincial Natural Science Foundation of China (Grant LR16A020001).


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Copyright information

© The Chinese Society of Theoretical and Applied Mechanics; Institute of Mechanics, Chinese Academy of Sciences and Springer-Verlag Berlin Heidelberg 2017

Authors and Affiliations

  1. 1.Department of Engineering Mechanics, Key Laboratory of Soft Machines and Smart Devices of Zhejiang ProvinceZhejiang UniversityHangzhouChina

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