Morphology of actin assemblies in response to polycation and salts.

Biomacromolecules

Graduate School of Science, Hokkaido University, Sapporo 060-0810, Japan, and SORST, JST, Sapporo, 060-0810, Japan.

Published: February 2006

F-actins are semi-flexible polyelectrolytes and can be assembled into a large polymer-actin complex with polymorphism through electrostatic interaction with polycations. This study investigates the structural phase behavior and the growth of polymer-actin complexes in terms of its longitudinal and lateral sizes in various polycation and KCl concentrations for a constant actin concentration. Our results show that the longitudinal growth and lateral growth of polymer-actin complexes, initiated by a common nucleation process, are dominated by different factors in subsequent growth process. This induces the structural polymorphism of polymer-actin complexes. Major factors to influence the polymorphism of polymer-actin complexes in polyelectrolyte systems have been discussed. Our results indicate that the semiflexible polyelectrolyte nature of F-actins is important for controlling the morphology and growth of actin architectures in cells.

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http://dx.doi.org/10.1021/bm050320gDOI Listing

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Biomacromolecules

February 2006

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