AlFx affects the formation of focal complexes by stabilizing the Arf-GAP ASAP1 in a complex with Arf1.
Aluminum fluoride (AlFx) is known to activate directly the alpha subunit of G-proteins but not the homologous small GTP-binding proteins. However, AlFx can stabilize complexes formed between Ras, RhoA or Cdc42 and their corresponding GTPase-activating proteins (GAPs). Here, we demonstrate that Arf1GDP can be converted into an active conformation by AlFx to form a complex with the Arf-GAP ASAP1 in vitro and in vivo. Within this complex ASAP1, which GAP activity is inoperative, can still alter the recruitment of paxillin to the focal complexes, thus indicating that ASAP1 interferes with focal complexes independently of its GAP activity.
Klein
Stéphanie
S
Institut de Pharmacologie Moléculaire et Cellulaire, CNRS-UMR 6097, Valbonne, France.
Franco
Michel
M
Chardin
Pierre
P
Luton
Frédéric
F
D020823:ADP-Ribosylation Factor 1 / Q000378:metabolism*; D020727:ADP-Ribosylation Factors / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D048868:Adaptor Proteins, Signal Transducing / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D017607:Aluminum Compounds / Q000494:pharmacology*; D000818:Animals; D002478:Cells, Cultured; D006224:Cricetinae; D005459:Fluorides / Q000494:pharmacology*; D020690:GTPase-Activating Proteins / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D014162:Transfection
D048868:Adaptor Proteins, Signal Transducing; D017607:Aluminum Compounds; D020690:GTPase-Activating Proteins; D020823:ADP-Ribosylation Factor 1; D020727:ADP-Ribosylation Factors; D005459:Fluorides; C032311:aluminum fluoride