Water Flux in Cell Motility: Expanding the Mechanisms of Membrane Protrusion

Transmembrane water fluxes through aquaporins (AQPs) are suggested to play, pivotal roles in cell polarization and directional cell motility. Local dilution by W water influences the dynamics of the subcortical actin polymerization and directs the formation of nascent membrane protrusions. In this paper. recent evidence is discussed in support of such a central role of AQP in membrane protrusion formation, and cell migration as a basis for our Understanding AQP9 Underlying molecular mechanisms of directional motility. Specifically. AQP9 in a physiological context controls transmembrane water fluxes driving, membrane protrusion formation, as an initial cellular response to a chemoattractant or other migratory signals. The importance of AQP-facilitated water fluxes in directional cell motility is underscored the observation that blocking or modifying specific sites in AQP9 also interferes with the molecular machinery that govern actin-mediated cellular shape changes. Cell Motil. Cytoskeleton 66: 237-247, 2009. (C) 2009 Wiley-Liss, Inc.