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Actin assembly at membranes controlled by ARF6

D A Schafer1, C D'Souza-Schorey, J A Cooper

  • 1Department of Cell Biology and Physiology, Washington University School of Medicine, St Louis, MO 63110, USA.

Traffic (Copenhagen, Denmark)
|March 29, 2001
PubMed

Insights

ADP-ribosylation factor-6 (ARF6) regulates actin assembly, driving vesicle movement and fluid uptake in cells. This GTPase controls actin remodeling at cell surfaces, impacting cellular processes like pinocytosis.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Biochemistry

Background:

  • ADP-ribosylation factor-6 (ARF6) is a small GTPase involved in membrane traffic and actin cytoskeleton remodeling.
  • Understanding ARF6's precise role in actin assembly is crucial for deciphering its cellular functions.

Purpose of the Study:

  • To investigate the function and mechanism of ARF6 in controlling actin assembly.
  • To elucidate the downstream effectors and signaling pathways regulated by ARF6.

Main Methods:

  • Real-time video analysis of actin assembly in living cells.
  • Expression of activated ARF6 to mimic its GTP-bound state.
  • Analysis of vesicle content and motility.

Main Results:

  • Activated ARF6 induced actin assembly, leading to the motility of vesicle-like particles, including pinosomes.
  • ARF6 stimulated actin assembly at ventral cell surface foci and enhanced fluid phase pinocytosis.
  • ARF6-induced particle motility required Arp2/3 complex, tyrosine kinase activity, phospholipase D (PLD), and D3-phosphoinositides, but not PI(4,5)P2.

Conclusions:

  • ARF6 plays a key role in regulating actin assembly for the motility of pinosomes.
  • ARF6 controls actin dynamics at specific cellular foci on the ventral cell surface.
  • ARF6 integrates signals through PLD and D3-phosphoinositides to modulate actin assembly and membrane trafficking.

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