RT Journal Article SR Electronic T1 Dynamic instability of the intracellular pressure drives bleb-based motility JF Journal of Cell Science JO J. Cell Sci. FD The Company of Biologists Ltd SP 3884 OP 3892 DO 10.1242/jcs.065672 VO 123 IS 22 A1 Maugis, Benoît A1 Brugués, Jan A1 Nassoy, Pierre A1 Guillen, Nancy A1 Sens, Pierre A1 Amblard, François YR 2010 UL http://jcs.biologists.org/content/123/22/3884.abstract AB We have demonstrated that the two- and three-dimensional motility of the human pathogenic parasite Entamoeba histolytica (Eh) depends on sustained instability of the intracellular hydrostatic pressure. This instability drives the cyclic generation and healing of membrane blebs, with typical protrusion velocities of 10–20 μm/second over a few hundred milliseconds and healing times of 10 seconds. The use of a novel micro-electroporation method to control the intracellular pressure enabled us to develop a qualitative model with three parameters: the rate of the myosin-driven internal pressure increase; the critical disjunction stress of membrane–cytoskeleton bonds; and the turnover time of the F-actin cortex. Although blebs occur randomly in space and irregularly time, they can be forced to occur with a defined periodicity in confined geometries, thus confirming our model. Given the highly efficient bleb-based motility of Eh in vitro and in vivo, Eh cells represent a unique model for studying the physical and biological aspects of amoeboid versus mesenchymal motility in two- and three-dimensional environments.