Single-Cell Biophysics: Measurement, Modulation, and Modeling

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Single-Cell Biophysics: Measurement, Modulation, and Modeling Poster Abstracts
47
5-POS Board 3
Brownian Dynamics Simulation Reveals Freedom of Motors in the Cargo Membrane Can
Influence Cargo Dynamics
Matt Bovyn1,2, Steven Gross3,1,2, Jun Allard4,1,2 .
1University of California - Irvine, Irvine, CA, USA, 4University of California - Irvine, Irvine,
CA, USA.3University of California - Irvine, Irvine, CA, USA, 2University of California - Irvine,
Irvine, CA, USA,
Active transport of subcellular cargos along microtubules is essential for organization and
function of eukaryotic cells. Kinesin family molecular motors are responsible for the transport of
some cargos, with multiple motors often active at once. These motors have been extensively
studied, but it remains unclear how the motors function in groups, as well as how properties of
the cargo itself can influence transport. We developed a Brownian dynamics simulator of cargo
transport which includes cargo shape and motor location on the cargo. Simulations reveal that if
motors are free to diffuse on the surface of a cargo, under certain circumstances motors self-
organize into dynamic clusters. Furthermore, dynamic clustering can give rise to the cargo
“memory” – when a travelling cargo becomes detached from the microtubule briefly, it will tend
to return to its former state more quickly when it regains contact. This memory effect
demonstrates that cargo geometry alone can influence cargo behavior and hints that dynamic
motor organization on the cargo could be used by the cell to control intracellular transport.