the role of traction in membrane curvature generation
Name: Haleh Alimohamadi
Grad Year: 2020
Membrane curvature can be generated by a variety of different molecular mechanisms such as protein scaffolding, heterogeneity, cytoskeletal forces that act as inputs. These mechanisms have the net effect of generating stresses on the bilayer that are translated into distinct final shapes of the membrane as outputs. We sought to reverse this input-output relationship by using the observed shape of a curved membrane to extract physical quantities such as the magnitude of the applied forces acting on the bilayer. To do this, we first calculated the normal and tangential tractions along the membrane surface using the shape and material properties of the bilayer. Then, externally applied forces were computed by taking a contour integral of tractions on the region boundary. We applied this approach to three different examples to demonstrate its utility - membrane tube formation, emergence of line tension at the interface of two spontaneous curvature fields, and the formation of podosome protrusions in human macrophage cells. These examples demonstrate that this analysis and accompanying workflow can be used to extract meaningful measurements of force and line tension from membrane shapes in a wide variety of biological contexts.
Industry Application Area(s)
Life Sciences/Medical Devices & Instruments