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Title: Diffusion of kinesin motors on cargo can enhance binding and run lengths during intracellular transport
Cellular cargoes, including lipid droplets and mitochondria, are transported along microtubules using molecular motors such as kinesins. Many experimental and computational studies focused on cargoes with rigidly attached motors, in contrast to many biological cargoes that have lipid surfaces that may allow surface mobility of motors. We extend a mechanochemical three-dimensional computational model by adding coupled-viscosity effects to compare different motor arrangements and mobilities. We show that organizational changes can optimize for different objectives: Cargoes with clustered motors are transported efficiently but are slow to bind to microtubules, whereas those with motors dispersed rigidly on their surface bind microtubules quickly but are transported inefficiently. Finally, cargoes with freely diffusing motors have both fast binding and efficient transport, although less efficient than clustered motors. These results suggest that experimentally observed changes in motor organization may be a control point for transport.  more » « less
Award ID(s):
1763272
PAR ID:
10222839
Author(s) / Creator(s):
; ; ;
Editor(s):
Mogilner, Alexander
Date Published:
Journal Name:
Molecular Biology of the Cell
Volume:
32
Issue:
9
ISSN:
1059-1524
Page Range / eLocation ID:
984 to 994
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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