SWAP-70 identifies a transitional subset of actin filaments in motile cells

Functionally different subsets of actin filament arrays contribute to cellular organization and motility. We report the identification of a novel subset of loose actin filament arrays through regulated association with the widely expressed protein SWAP-70. These loose actin filament arrays were comm...

Full description

Saved in:
Bibliographic Details
Published in:Molecular biology of the cell 2003-08, Vol.14 (8), p.3242-3253
Main Authors: Hilpelä, Pirta, Oberbanscheidt, Pia, Hahne, Penelope, Hund, Martin, Kalhammer, Georg, Small, J Victor, Bähler, Martin
Format: Article
Language:English
Subjects:
Actin Cytoskeleton - metabolism
Animals
Cell Movement - physiology
Cells, Cultured
Cloning, Molecular
DNA-Binding Proteins - metabolism
Guanine Nucleotide Exchange Factors
HeLa Cells
Humans
Mice
Minor Histocompatibility Antigens
Mutation
Myosins - metabolism
Nuclear Proteins - metabolism
Phosphatidylinositol 3-Kinases - metabolism
Protein Binding
Protein Structure, Tertiary
Pseudopodia - metabolism
Swiss 3T3 Cells
Two-Hybrid System Techniques
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Functionally different subsets of actin filament arrays contribute to cellular organization and motility. We report the identification of a novel subset of loose actin filament arrays through regulated association with the widely expressed protein SWAP-70. These loose actin filament arrays were commonly located behind protruding lamellipodia and membrane ruffles. Visualization of these loose actin filament arrays was dependent on lamellipodial protrusion and the binding of the SWAP-70 PH-domain to a 3'-phosphoinositide. SWAP-70 with a functional pleckstrin homology-domain lacking the C-terminal 60 residues was targeted to the area of the loose actin filament arrays, but it did not associate with actin filaments. The C-terminal 60 residues were sufficient for actin filament association, but they provided no specificity for the subset of loose actin filament arrays. These results identify SWAP-70 as a phosphoinositide 3-kinase signaling-dependent marker for a distinct, hitherto unrecognized, array of actin filaments. Overexpression of SWAP-70 altered the actin organization and lamellipodial morphology. These alterations were dependent on a proper subcellular targeting of SWAP-70. We propose that SWAP-70 regulates the actin cytoskeleton as an effector or adaptor protein in response to agonist stimulated phosphatidylinositol (3,4)-bisphosphate production and cell protrusion.
ISSN:1059-1524
1939-4586
DOI:10.1091/mbc.E03-01-0043