Podosome assembly is controlled by the GTPase ARF1 and its nucleotide exchange factor ARNO
| Autor: | Tingting Jiang, Cheng-han Yu, Zi Zhao Lieu, Paul Matsudaira, Gareth E. Jones, Alexander D. Bershadsky, Nisha Bte Mohd Rafiq |
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| Rok vydání: | 2016 |
| Předmět: |
0301 basic medicine
Time Factors RHOA Podosome Recombinant Fusion Proteins Golgi Apparatus GTPase Transfection Article Nucleotide exchange factor Mice 03 medical and health sciences 0302 clinical medicine Cell Line Tumor Animals Humans Enzyme Inhibitors Spotlight Research Articles rho-Associated Kinases biology Nonmuscle Myosin Type IIA GTPase-Activating Proteins Cell Membrane Cell Biology Actin cytoskeleton Actins Cell biology Actin Cytoskeleton Protein Transport 030104 developmental biology Microscopy Fluorescence Podosomes Podosome assembly Commentary biology.protein ADP-Ribosylation Factor 1 RNA Interference Guanosine Triphosphate Guanine nucleotide exchange factor rhoA GTP-Binding Protein 030217 neurology & neurosurgery Signal Transduction Podosome core |
| Zdroj: | The Journal of Cell Biology Rafiq, N B M, Lieu, Z Z, Jiang, T, Yu, C H, Matsudaira, P, Jones, G E & Bershadsky, A D 2017, ' Podosome assembly is controlled by the GTPase ARF1 and its nucleotide exchange factor ARNO ', The Journal of cell biology, vol. 216, no. 1, pp. 181-197 . https://doi.org/10.1083/jcb.201605104 |
| ISSN: | 1540-8140 0021-9525 |
| DOI: | 10.1083/jcb.201605104 |
| Popis: | Rafiq et al. demonstrate that the small G protein ARF1 and its activator, cytohesin 2 (ARNO), are required for podosome formation in macrophage-like cells and fibroblasts. Inhibition of ARNO-ARF1 signaling results in increased RhoA activity and disassembly of podosomes in a myosin-IIA–dependent fashion. In fibroblasts that normally do not form podosomes, constitutively active ARF1 induces actin-rich puncta associated with sites of matrix degradation, putative precursors of podosomes. Podosomes represent a class of integrin-mediated cell-matrix adhesions formed by migrating and matrix-degrading cells. We demonstrate that in macrophage-like THP1 cells and fibroblasts stimulated to produce podosomes, down-regulation of the G-protein ARF1 or the ARF1 guanine nucleotide exchange factor, ARNO, by small, interfering RNA or pharmacological inhibitors led to striking podosome elimination. Concomitantly, treatments inducing podosome formation increased the level of guanosine triphosphate (GTP)–bound ARF1. ARNO was found to colocalize with the adhesive rings of podosomes, whereas ARF1 was localized to vesicular structures transiently contacting podosome rings. Inhibition of ARF1 led to an increase in RhoA-GTP levels and triggered assembly of myosin-IIA filaments in THP1 cells, whereas the suppression of myosin-IIA rescued podosome formation regardless of ARF1 inhibition. Finally, expression of constitutively active ARF1 in fibroblasts induced formation of putative podosome precursors: actin-rich puncta coinciding with matrix degradation sites and containing proteins of the podosome core but not of the adhesive ring. Thus, ARNO-ARF1 regulates formation of podosomes by inhibition of RhoA/myosin-II and promotion of actin core assembly. |
| Databáze: | OpenAIRE |
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