Rab-coupling protein coordinates recycling of alpha5beta1 integrin and EGFR1 to promote cell migration in 3D microenvironments.
Here we show that blocking the adhesive function of alphavbeta3 integrin with soluble RGD ligands, such as osteopontin or cilengitide, promoted association of Rab-coupling protein (RCP) with alpha5beta1 integrin and drove RCP-dependent recycling of alpha5beta1 to the plasma membrane and its mobilization to dynamic ruffling protrusions at the cell front. These RCP-driven changes in alpha5beta1 trafficking led to acquisition of rapid/random movement on two-dimensional substrates and to a marked increase in fibronectin-dependent migration of tumor cells into three-dimensional matrices. Recycling of alpha5beta1 integrin did not affect its regulation or ability to form adhesive bonds with substrate fibronectin. Instead, alpha5beta1 controlled the association of EGFR1 with RCP to promote the coordinate recycling of these two receptors. This modified signaling downstream of EGFR1 to increase its autophosphorylation and activation of the proinvasive kinase PKB/Akt. We conclude that RCP provides a scaffold that promotes the physical association and coordinate trafficking of alpha5beta1 and EGFR1 and that this drives migration of tumor cells into three-dimensional matrices.
Beatson Institute for Cancer Research, Bearsden, Glasgow G61 1BD, Scotland, UK.
Patrick T
PT
Caswell
May
M
Chan
Andrew J
AJ
Lindsay
Mary W
MW
McCaffrey
David
D
Boettiger
Jim C
JC
Norman
D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000187:drug effects / Q000502:physiology*; D022081:Cell Surface Extensions / Q000502:physiology; D004815:Epidermal Growth Factor / Q000494:pharmacology; D066246:ErbB Receptors / Q000235:genetics / Q000378:metabolism*; D005353:Fibronectins / Q000378:metabolism / Q000494:pharmacology; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D039081:Integrin alpha5beta1 / Q000378:metabolism*; D039302:Integrin alphaVbeta3 / Q000037:antagonists & inhibitors / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D009154:Mutation; D053495:Osteopontin / Q000494:pharmacology; D010446:Peptide Fragments / Q000235:genetics; D010766:Phosphorylation / Q000187:drug effects; D011485:Protein Binding; D021381:Protein Transport / Q000187:drug effects / Q000502:physiology; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D012910:Snake Venoms / Q000494:pharmacology; D014162:Transfection; D020691:rab GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism; D000099193:rab11 GTP-Binding Proteins
D048868:Adaptor Proteins, Signal Transducing; D004815:Epidermal Growth Factor; D066246:ErbB Receptors; D005353:Fibronectins; D049452:Green Fluorescent Proteins; D039081:Integrin alpha5beta1; D039302:Integrin alphaVbeta3; D008565:Membrane Proteins; D053495:Osteopontin; D010446:Peptide Fragments; D011993:Recombinant Fusion Proteins; D012910:Snake Venoms; D020691:rab GTP-Binding Proteins; D000099193:rab11 GTP-Binding Proteins; C488966:RAB11FIP1 protein, human; C422910:Cilengitide; C512478:EGFR protein, human