Aluminum Fluoride Stimulates Surface Protrusions in Cells Overexpressing the ARF6 GTPase

• Published in: The Journal of cell biology Vol. 134; no. 4; pp. 935 - 947
• Main Authors: Radhakrishna, Harish, Klausner, Richard D., Donaldson, Julie G.
• Format: Journal Article
• Language: English
• Published: United States Rockefeller University Press 01.08.1996; The Rockefeller University Press
• Subjects: Actins; Actins - metabolism; ADP-Ribosylation Factor 1; ADP-Ribosylation Factors; Aluminum Compounds - pharmacology; Antibodies; Arachidonic Acid - metabolism; Cell Adhesion Molecules - analysis; Cell Membrane - drug effects; Cell Membrane - metabolism; Cell membranes; Cell surface extensions; Cells; Cellular biology; Clathrin - analysis; Cortactin; COS cells; Cytochalasin D - pharmacology; Fluorides - pharmacology; Focal Adhesion Kinase 1; Focal Adhesion Protein-Tyrosine Kinases; Gelsolin - analysis; GTP Phosphohydrolases - analysis; GTP Phosphohydrolases - biosynthesis; GTP Phosphohydrolases - genetics; GTP Phosphohydrolases - metabolism; GTP-Binding Proteins - analysis; GTP-Binding Proteins - biosynthesis; GTP-Binding Proteins - genetics; GTP-Binding Proteins - metabolism; HeLa Cells; Humans; Lipoxygenase Inhibitors - pharmacology; Masoprocol - pharmacology; Membrane Proteins - analysis; Membrane Proteins - biosynthesis; Membrane Proteins - genetics; Membrane Proteins - metabolism; Microfilament Proteins - analysis; Molecular biology; Mutation; P branes; Phospholipases A - antagonists & inhibitors; Pinocytosis; Protein-Tyrosine Kinases - analysis; Proteins; Pseudopodia - drug effects; rac GTP-Binding Proteins; rhoA GTP-Binding Protein; Swiss 3T3 cells; Transfection; Transferrin - metabolism; Transferrins
• ISSN: 0021-9525; 1540-8140
• DOI: 10.1083/jcb.134.4.935

To study the effector function of the ADP-ribosylation factor (ARF) 6 GTP-binding protein, we transfected HeLa cells with wild-type, epitope-tagged ARF6. Previously shown to indirectly activate the ARF1 GTPase, aluminum fluoride (AlF) treatment of ARF6-transfected cells resulted in a redistribution of both ARF6 and actin to discrete sites on the plasma membrane, which became increasingly protrusive over time. The effects of AlF were reversible, specific to cells transfected with wild-type ARF6, and resembled the cellular protrusions observed in cells expressing the GTPase defective mutant of ARF6. Importantly, the protrusions observed in cells transfected with ARF6 were distinct from the enhanced stress fibers and membrane ruffles observed in cells transfected with RhoA and Rac1, respectively. In cells forming protrusions, there was an apparent stimulation of macropinocytosis and membrane recycling within the protrusive structures. In contrast, no block in transferrin uptake or alteration of the distribution of clathrin AP-2 complexes was detected in these cells. The AlF-induced, ARF6-dependent formation of protrusive structures was blocked by cytochalasin D and inhibitors of the lipoxygenase pathway. These observations support a novel role for the ARF6 GTPase in modeling the plasma membrane and underlying cytoskeleton.