Akt-mediated phosphorylation of the G protein-coupled receptor EDG-1 is required for endothelial cell chemotaxis.
The role of the protein kinase Akt in cell migration is incompletely understood. Here we show that sphingosine-1-phosphate (S1P)-induced endothelial cell migration requires the Akt-mediated phosphorylation of the G protein-coupled receptor (GPCR) EDG-1. Activated Akt binds to EDG-1 and phosphorylates the third intracellular loop at the T(236) residue. Transactivation of EDG-1 by Akt is not required for G(i)-dependent signaling but is indispensable for Rac activation, cortical actin assembly, and chemotaxis. Indeed, T236AEDG-1 mutant sequestered Akt and acted as a dominant-negative GPCR to inhibit S1P-induced Rac activation, chemotaxis, and angiogenesis. Transactivation of GPCRs by Akt may constitute a specificity switch to integrate rapid G protein-dependent signals into long-term cellular phenomena such as cell migration.
Lee
M J
MJ
Center for Vascular Biology and Department of Physiology, University of Connecticut Health Center, Farmington, CT 06030, USA.
Thangada
S
S
Paik
J H
JH
Sapkota
G P
GP
Ancellin
N
N
Chae
S S
SS
Wu
M
M
Morales-Ruiz
M
M
Sessa
W C
WC
Alessi
D R
DR
Hla
T
T
D000199:Actins / Q000378:metabolism; D000818:Animals; D002460:Cell Line; D002633:Chemotaxis / Q000502:physiology*; D004730:Endothelium, Vascular / Q000166:cytology* / Q000187:drug effects; D004789:Enzyme Activation / Q000502:physiology; D006801:Humans; D017874:Immediate-Early Proteins / Q000378:metabolism*; D008246:Lysophospholipids; D008954:Models, Biological; D018919:Neovascularization, Physiologic / Q000502:physiology; D010766:Phosphorylation; D011485:Protein Binding; D017346:Protein Serine-Threonine Kinases; D017434:Protein Structure, Tertiary; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism*; D051057:Proto-Oncogene Proteins c-akt; D011956:Receptors, Cell Surface; D043562:Receptors, G-Protein-Coupled; D049312:Receptors, Lysophospholipid; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology*; D013110:Sphingosine / Q000031:analogs & derivatives / Q000494:pharmacology; D020744:rac GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism
D000199:Actins; D017874:Immediate-Early Proteins; D008246:Lysophospholipids; D011518:Proto-Oncogene Proteins; D011956:Receptors, Cell Surface; D043562:Receptors, G-Protein-Coupled; D049312:Receptors, Lysophospholipid; D011993:Recombinant Fusion Proteins; C060506:sphingosine 1-phosphate; C494918:AKT1 protein, human; D017346:Protein Serine-Threonine Kinases; D051057:Proto-Oncogene Proteins c-akt; D020744:rac GTP-Binding Proteins; D013110:Sphingosine