< Back to Article

Structural organization and energy storage in crosslinked actin assemblies

Fig 5

Straining of crosslinkers and energy storage.

(A-C) Probability density distribution (PDF) of the extensional strains (top) and torsional strains (bottom) of crosslinkers with various stiffness values as indicated above the figure, at the end of individual simulations (t = 50s). For comparison, red lines indicate the corresponding Boltzmann distributions of a free spring with the same stiffness, and , where C₁ and C₂ are the normalization constants for ϵ ∈ (−1, ∞) and θ ∈ (0, π) respectively. Note that for the extensional strain, when we calculate the Boltzmann distribution, the energy contribution from steric interactions, which lead to the empty region at highly negative strains in the histogram, is neglected. (D, E) Average absolute value of the extensional strain ϵ (D) and the corresponding extensional energy E_ext (E) as a function of the extensional stiffness κ_ext. (F, G) Average torsional strain θ (F) and the corresponding torsional energy E_tor (G) as a function of the torsional stiffness κ_tor. In (D-G), simulations are performed for filaments of various lengths: 81nm (blue), 135nm (red), and 189nm (orange). For each simulation, the means of the energy were calculated from the data between 40s to 50s and the error bars indicate standard deviation over 10 simulations. Energies corresponding to the networks in panels (A-C) are identified by the red symbols with corresponding shapes.

doi: https://doi.org/10.1371/journal.pcbi.1006150.g005