Details

Autor(en) / Beteiligte

• Paleotti, Olivia
• Macia, Eric
• Luton, Frederic
• Klein, Stephanie
• Partisani, Mariagrazia
• Chardin, Pierre
• Kirchhausen, Tom
• Franco, Michel

Titel

The Small G-protein Arf6GTP Recruits the AP-2 Adaptor Complex to Membranes

Ist Teil von

• The Journal of biological chemistry, 2005-06, Vol.280 (22), p.21661-21666

Ort / Verlag

United States: Elsevier Inc

Erscheinungsjahr

2005

Quelle

MEDLINE

Beschreibungen/Notizen

• The small GTP-binding protein ADP-ribosylation factor 6 (Arf6) is involved in plasma membrane/endosomes trafficking. However, precisely how the activation of Arf6 regulates vesicular transport is still unclear. Here, we show that, in vitro, recombinant Arf6GTP recruits purified clathrin-adaptor complex AP-2 (but not AP-1) onto phospholipid liposomes in the absence of phosphoinositides. We also show that phosphoinositides and Arf6 tightly cooperate to translocate AP-2 to the membrane. In vivo, Arf6GTP (but not Arf6GDP) was found associated to AP-2. The expression of the GTP-locked mutant of Arf6 leads to the plasma membrane redistribution of AP-2 in Arf6GTP-enriched areas. Finally, we demonstrated that the expression of the GTP-locked mutant of Arf6 inhibits transferrin receptor internalization without affecting its recycling. Altogether, our results demonstrated that Arf6GTP interacts specifically with AP-2 and promotes its membrane recruitment. These findings strongly suggest that Arf6 plays a major role in clathrin-mediated endocytosis by directly controlling the assembly of the AP-2/clathrin coat.