Differential Localization of Rho Gtpases in Live Cells
| Autor: | Mark G. Rush, Mark R. Philips, David Michaelson, Peter D'Eustachio, Joseph Silletti, Gretchen A. Murphy |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2001 |
| Předmět: |
green fluorescent protein
rho GTP-Binding Proteins RHOA Endosome RHOB Recombinant Fusion Proteins Green Fluorescent Proteins Molecular Sequence Data Palmitic Acid CHO Cells Cell Line 03 medical and health sciences symbols.namesake Mice 0302 clinical medicine Geranylgeranylation Dogs Palmitoylation Rho Cricetinae RhoB GTP-Binding Protein Chlorocebus aethiops Animals rho-Specific Guanine Nucleotide Dissociation Inhibitors Endomembrane system Amino Acid Sequence 030304 developmental biology Guanine Nucleotide Dissociation Inhibitors 0303 health sciences Cdc42hs biology Cell Membrane Biological Transport Cell Biology 3T3 Cells Golgi apparatus RhoGDI Cell biology Rac Luminescent Proteins 030220 oncology & carcinogenesis COS Cells biology.protein symbols Original Article |
| Zdroj: | The Journal of Cell Biology |
| ISSN: | 1540-8140 0021-9525 |
| Popis: | Determinants of membrane targeting of Rho proteins were investigated in live cells with green fluorescent fusion proteins expressed with or without Rho-guanine nucleotide dissociation inhibitor (GDI)alpha. The hypervariable region determined to which membrane compartment each protein was targeted. Targeting was regulated by binding to RhoGDI alpha in the case of RhoA, Rac1, Rac2, and Cdc42hs but not RhoB or TC10. Although RhoB localized to the plasma membrane (PM), Golgi, and motile peri-Golgi vesicles, TC10 localized to PMs and endosomes. Inhibition of palmitoylation mislocalized H-Ras, RhoB, and TC10 to the endoplasmic reticulum. Although overexpressed Cdc42hs and Rac2 were observed predominantly on endomembrane, Rac1 was predominantly at the PM. RhoA was cytosolic even when expressed at levels in vast excess of RhoGDI alpha. Oncogenic Dbl stimulated translocation of green fluorescent protein (GFP)-Rac1, GFP-Cdc42hs, and GFP-RhoA to lamellipodia. RhoGDI binding to GFP-Cdc42hs was not affected by substituting farnesylation for geranylgeranylation. A palmitoylation site inserted into RhoA blocked RhoGDI alpha binding. Mutations that render RhoA, Cdc42hs, or Rac1, either constitutively active or dominant negative abrogated binding to RhoGDI alpha and redirected expression to both PMs and internal membranes. Thus, despite the common essential feature of the CAAX (prenylation, AAX tripeptide proteolysis, and carboxyl methylation) motif, the subcellular localizations of Rho GTPases, like their functions, are diverse and dynamic. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|