Alterations in the Arf6-regulated plasma membrane endosomal recycling pathway in cells overexpressing the tetraspan protein Gas3/PMP22.

Abstract

Growth arrest specific 3 (Gas3)/peripheral myelin protein 22 (PMP22) is a component of the compact peripheral nerve myelin, and mutations affecting gas3/PMP22 gene are responsible for a group of peripheral neuropathies in humans. We have performed in vivo imaging in order to investigate in detail the phenotype induced by Gas3/PMP22 overexpression in cultured cells. Here we show that Gas3/PMP22 triggers the accumulation of vacuoles, before the induction of cell death or of changes in cell spreading. Overexpressed Gas3/PMP22 accumulates into two distinct types of intracellular membrane compartments. Gas3/PMP2 accumulates within late endosomes close to the juxtanuclear region, whereas in the proximity of the cell periphery, it induces the formation of actin/phosphatidylinositol (4,5)-bisphosphate (PIP(2))-positive large vacuoles. Gas3/PMP22-induced vacuoles do not contain transferrin receptor, but instead they trap membrane proteins that normally traffic through the ADP-ribosylation factor 6 (Arf6) endosomal compartment. Arf6 and Arf6-Q67L co-localize with Gas3/PMP22 in these vacuoles, and the dominant negative mutant of Arf6, T27N, blocks the appearance of vacuoles in response to Gas3/PMP22, but not its accumulation in the late endosomes. Finally a point mutant of Gas3/PMP22 responsible for the Charcot-Marie-Tooth 1A disease is unable to trigger the accumulation of PIP(2)-positive vacuoles. Altogether these results suggest that increased Gas3/PMP22 levels can alter membrane traffic of the Arf6 plasma-membrane-endosomal recycling pathway and show that, similarly to other tetraspan proteins, Gas3/PMP22 can accumulate in the late endosomes.

• Authors: Romina Chies, Lucilla Nobbio, Paolo Edomi, Angelo Schenone, Claudio Schneider, Claudio Brancolini
• Journal: Journal of cell science (J Cell Sci) Vol. 116 Issue Pt 6 Pg. 987-99 (Mar 15 2003) ISSN: 0021-9533 [Print] England
• PMID: 12584243 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• ADP-Ribosylation Factor 6
• Actins
• Indicators and Reagents
• Intracellular Signaling Peptides and Proteins
• Luminescent Proteins
• Lysophospholipids
• Monoglycerides
• Myelin Proteins
• Pmp22 protein, mouse
• Pmp22 protein, rat
• Proto-Oncogene Proteins c-bcl-2
• Recombinant Fusion Proteins
• bis(monoacylglyceryl)phosphate
• Green Fluorescent Proteins
• Protein Serine-Threonine Kinases
• rho-Associated Kinases
• ADP-Ribosylation Factors
• ARF6 protein, human
• Arf6 protein, mouse
• Arf6 protein, rat

Topics

• 3T3 Cells
• ADP-Ribosylation Factor 6
• ADP-Ribosylation Factors (metabolism)
• Actins (metabolism)
• Animals
• Cell Membrane (metabolism)
• Endosomes (metabolism)
• Gene Expression
• Green Fluorescent Proteins
• Indicators and Reagents (metabolism)
• Intracellular Signaling Peptides and Proteins
• Luminescent Proteins (genetics)
• Lysophospholipids (metabolism)
• Mice
• Monoglycerides
• Myelin Proteins (genetics, metabolism)
• Peripheral Nervous System Diseases (metabolism)
• Protein Serine-Threonine Kinases (metabolism)
• Protein Transport (physiology)
• Proto-Oncogene Proteins c-bcl-2 (genetics)
• Rats
• Recombinant Fusion Proteins (genetics, metabolism)
• Schwann Cells (cytology)
• Sciatic Nerve (cytology)
• Vacuoles (metabolism)
• rho-Associated Kinases