Hydrodynamic flow caused by active transport along cytoskeletal elementsD. Houtman1, I. Pagonabarraga2, C. P. Lowe1, A. Esseling-Ozdoba3, A. M. C. Emons3 and E. Eiser1
1 Van 't Hoff Institute for Molecular Sciences (HIMS), Universiteit van Amsterdam - Nieuwe Achtergracht 166, 1018 WV Amsterdam, The Netherlands
2 Departament de Física Fonamental, Universitat de Barcelona - Carrer Martí i Franqués 1, 08028-Barcelona, Spain
3 Wageningen University, Laboratory of Plant Cell Biology - Arboretumlaan 4, 6703 BD Wageningen, The Netherlands
received 9 July 2006; accepted in final form 12 February 2007; published April 2007
published online 14 March 2007
We develop a simple lattice model to describe the hydrodynamic influence of active mass transport along bio-filaments on freely diffusing mass in the cell. To quantify the overall mass transport we include Brownian motion, excluded volume interactions, active transport along the filaments, and hydrodynamic interactions. The model shows that the hydrodynamic forces induced by molecular motors attached to the filaments give rise to a non-negligible flux close to the filament. This additional flux appears to have two effects. Depending on the degree of filament occupation it can exert a sufficiently large influence on unbound motors and cargo to modify their transport and also regulate the flux of motors bound to the filament. We expect such a mechanism is important in situations found in plant cells, where directional transport spans the entire cell. In particular, it can explain the cytoplasmic streaming observed in plant cells.
87.16.Nn - Motor proteins (myosin, kinesin dynein).
67.40.Hf - Hydrodynamics in specific geometries, flow in narrow channels.
05.40.-a - Fluctuation phenomena, random processes, noise, and Brownian motion.
© Europhysics Letters Association 2007