RhoB and actin polymerization coordinate Src activation with endosome-mediated delivery to the membrane.
We have used a c-Src-GFP fusion protein to address the spatial control of Src activation and the nature of Src-associated intracellular structures during stimulus-induced transit to the membrane. Src is activated during transit, particularly in RhoB-containing cytoplasmic endosomes associated with the perinuclear recycling compartment. Knocking out RhoB or expressing a dominant-interfering Rab11 mutant suppresses both catalytic activation of Src and translocation of active kinase to peripheral membrane structures. In addition, the Src- and RhoB-containing endosomes harbor proteins involved in actin polymerization and filament assembly, for example Scar1, and newly polymerized actin can associate with these endosomes in a Src-dependent manner. This implies that Src may regulate an endosome-associated actin nucleation activity. In keeping with this, Src controls the actin dependence of RhoB endosome movement toward the plasma membrane. This work identifies RhoB as a component of "outside-in" signaling pathways that coordinate Src activation with translocation to transmembrane receptors.
Sandilands
Emma
E
The Beatson Institute for Cancer Research, Cancer Research UK Beatson Laboratories, Garscube Estate, Switchback Road, Bearsden, Glasgow G61 1BD, United Kingdom.
Cans
Christophe
C
Fincham
Valerie J
VJ
Brunton
Valerie G
VG
Mellor
Harry
H
Prendergast
George C
GC
Norman
Jim C
JC
Superti-Furga
Giulio
G
Frame
Margaret C
MC
D016475:3T3 Cells; D000199:Actins / Q000378:metabolism*; D000818:Animals; D002384:Catalysis; D002448:Cell Adhesion; D002462:Cell Membrane / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D003599:Cytoskeleton / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D011992:Endosomes / Q000378:metabolism*; D005353:Fibronectins / Q000378:metabolism; D005799:Genes, Dominant; D049452:Green Fluorescent Proteins / Q000378:metabolism; D047468:Immunoprecipitation; D051379:Mice; D008856:Microscopy, Fluorescence; D010957:Plasmids / Q000378:metabolism; D010982:Platelet-Derived Growth Factor / Q000378:metabolism; D021381:Protein Transport; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D015398:Signal Transduction; D020691:rab GTP-Binding Proteins / Q000378:metabolism; D020743:rhoB GTP-Binding Protein / Q000378:metabolism*; D019061:src-Family Kinases / Q000378:metabolism*; D000099193:rab11 GTP-Binding Proteins
D000199:Actins; D005353:Fibronectins; D049452:Green Fluorescent Proteins; D010982:Platelet-Derived Growth Factor; D011993:Recombinant Fusion Proteins; D020691:rab GTP-Binding Proteins; D020743:rhoB GTP-Binding Protein; D019061:src-Family Kinases; D000099193:rab11 GTP-Binding Proteins