Conformational dynamics of neurofilament side-arms

Mark J. Stevens, Jan H. Hoh

Research output: Contribution to journalArticle

Abstract

The side-arms of neurofilaments (NFs) have been proposed to be highly disordered, leading to entropic repulsion that modulates interfilament spacing. To gain further insight into the dynamics and organization of the side-arms, we performed molecular dynamics simulations of neurofilament brushes using a coarse-grained model. The density profiles for three NF proteins, NF-L, NF-M, and phosphorylated NF-H (NF-HP), grafted to planar surfaces were calculated and examined as a function of component (salt, residues) and as a function of charge. Analysis of these profiles reveals that the NF with the shortest side arm, NF-L, is disproportionately long compared to the other NFs. The reason for difference is that NF-L is effectively a strong polyelectrolyte, while NF-M and NF-HP are effectively weaker polyelectrolytes. Further, we find cross-correlations between neurofilament side-arms within the brush, even for the NF-L polymers. These correlations occur because of strong attractions between the long sequence repeats of negative residues and the long postive residue repeats and impart a time average structure of the neurofilament brush that deviates from an ideal polymer in a solvent.

Original languageEnglish (US)
Pages (from-to)8879-8886
Number of pages8
JournalJournal of Physical Chemistry B
Volume114
Issue number27
DOIs
StatePublished - Jul 15 2010

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Intermediate Filaments
Brushes
brushes
Polyelectrolytes
Polymers
Neurofilament Proteins
Molecular dynamics
polymers
profiles
Salts
cross correlation
attraction
Proteins
spacing
Computer simulation
molecular dynamics
salts
proteins
simulation
Molecular Dynamics Simulation

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry
  • Materials Chemistry
  • Surfaces, Coatings and Films
  • Medicine(all)

Cite this

Conformational dynamics of neurofilament side-arms. / Stevens, Mark J.; Hoh, Jan H.

In: Journal of Physical Chemistry B, Vol. 114, No. 27, 15.07.2010, p. 8879-8886.

Research output: Contribution to journalArticle

Stevens, Mark J. ; Hoh, Jan H. / Conformational dynamics of neurofilament side-arms. In: Journal of Physical Chemistry B. 2010 ; Vol. 114, No. 27. pp. 8879-8886.
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