Domain unfolding in neurofilament sidearms: effects of phosphorylation and ATP

FEBS Letters

Leterrier, Jean-François²  Aranda-Espinoza, Helim³  Carl, Philippe¹  Discher, Dennis E³  Janmey, Paul³ 

[1]Biophysical Engineering Laboratory, Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, PA 19104, USA

[2]UMR 6558 CNRS, Poitiers, France

[3]Institute for Medicine and Engineering, 1080 Vagelos Research Laboratory, 3340 Smith Walk, University of Pennsylvania, Philadelphia, PA 19104, USA

关键词: Neurofilament;    Sidearm;    Phosphorylation;    Intermediate filament;    aa;    amino acid;    AFM;    atomic force microscopy;    ATP;    adenosine triphosphate;    DLS;    dynamic light scattering;    MAP;    microtubule associated proteins;    NF;    neurofilaments;    NF-L;    neurofilament light chain;    NF-M;    neurofilament medium chain;    NF-H;    neurofilament heavy chain;    MT;    microtubules;    RB;    reassembly buffer;    SA;    sidearms;    p-SA;    phosphorylated sidearms;    p-SAT;    phosphorylated sidearms plus ATP;    dp-SA;    dephosphorylated sidearms;    I27;    human cardiac titin I band module 27;    SDS–PAGE;    sodium dodecyl sulfate polyacrylamide gel electrophoresis;   

DOI  :  10.1016/S0014-5793(02)03515-9

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Lateral projections of neurofilaments (NF) called sidearms (SA) affect axon stability and caliber. SA phosphorylation is thought to modulate inter-NF distance and interactions between NF and other subcellular organelles. SA were probed by atomic force microscopy (AFM) and dynamic light scattering (DLS) as a function of phosphorylation and ATP content. DLS shows SA are larger when phosphorylated, and AFM shows four unfoldable domains in SA regardless of phosphorylation state or the presence of ATP. However, the native phosphorylated SA requires three-fold higher force to unfold by AFM than dephosphorylated SA, suggesting a less pliant as well as larger structure when phosphorylated.

【 授权许可】

Unknown