Estimated stall force for one actin filament in keratocyte

Range ~4 pN
Organism Trout Oncorhynchus mykiss
Reference Sens P, Plastino J. Membrane tension and cytoskeleton organization in cell motility. J Phys Condens Matter. 2015 Jul 15 27(27):273103. doi: 10.1088/0953-8984/27/27/273103. p.6 right column top paragraphPubMed ID26061624
Primary Source [47] Prass M, Jacobson K, Mogilner A and Radmacher M 2006 Direct measurement of the lamellipodial protrusive force in a migrating cell J. Cell Biol. 174 767–72PubMed ID16966418
Method Primary source abstract: "[Investigators] place an atomic force microscopy cantilever in the path of a migrating keratocyte. The deflection of the cantilever, which occurs over a period of approximately 10 s, provides a direct measure of the force exerted by the lamellipodial leading edge."
Comments P.6 right column top paragraph: "The stall tension at which the membrane prevents actin polymerization can thus be estimated as σstall = fstall×ρactin/2. For the keratocyte, the stall force for one actin filament has been estimated as fstall ≈ 4 pN [primary source]. Using ρactin ≈ 100 filaments μm^-1, one finds σstall ≈ 200 pN μm^−1. Since the membrane tension of the keratocyte is similar to σstall (table 1 BNID 112509), this suggests that the cytoskeleton assembles until membrane tension reaches a point where it is significantly contributing to slowing actin polymerization. Generalizing to other cell types, the σstall characteristic of the cell, as defined by the architecture of its cytoskeleton, would then define the homeostatic membrane tension maintained by the cell."
Entered by Uri M
ID 112513