Non-uniform distribution of myosin-mediated forces governs red blood cell membrane curvature through tension modulation
Fig 7
The role of effective tension.
Effective membrane tension is a key parameter in regulating the RBC biconcave shape in addition to applied forces in the dimple and rim regions. (A-C) Heat maps show the total error in the shape of the simulated RBCs for (A) low tension (tension = 10−4 pN/nm), (B) intermediate tension (tension = 10−3 pN/nm), and (C) high tension (tension = 10−2 pN/nm). In each heat map, the point with the minimum error is marked with X. Also, for each marked point, the volume of the simulated RBC (V) is calculated using Eq. S13b in S1 Text, and the shape (solid yellow line) is shown in comparison with the reference parametric shape (dotted blue line). At intermediate tension, the shape error has the lowest value when Fratio = 1.27 consistent with our experimental results in Fig 6. (D-F) The calculated shape error (Eq 8) as a function of the dimple force density (Fdimple) for different values of the force density at the rim region and the membrane tension.