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Clayton NS, Hodge RG, Infante E, Alibhai D, Zhou F, Ridley AJ. RhoU forms homo-oligomers to regulate cellular responses. J Cell Sci 2024; 137:jcs261645. [PMID: 38180080 PMCID: PMC10917059 DOI: 10.1242/jcs.261645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Accepted: 12/21/2023] [Indexed: 01/06/2024] Open
Abstract
RhoU is an atypical member of the Rho family of small G-proteins, which has N- and C-terminal extensions compared to the classic Rho GTPases RhoA, Rac1 and Cdc42, and associates with membranes through C-terminal palmitoylation rather than prenylation. RhoU mRNA expression is upregulated in prostate cancer and is considered a marker for disease progression. Here, we show that RhoU overexpression in prostate cancer cells increases cell migration and invasion. To identify RhoU targets that contribute to its function, we found that RhoU homodimerizes in cells. We map the region involved in this interaction to the C-terminal extension and show that C-terminal palmitoylation is required for self-association. Expression of the isolated C-terminal extension reduces RhoU-induced activation of p21-activated kinases (PAKs), which are known downstream targets for RhoU, and induces cell morphological changes consistent with inhibiting RhoU function. Our results show for the first time that the activity of a Rho family member is stimulated by self-association, and this is important for its activity.
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Affiliation(s)
- Natasha S. Clayton
- School of Cellular and Molecular Medicine, University of Bristol, Biomedical Sciences Building, University Walk, Bristol BS8 1TD, UK
| | - Richard G. Hodge
- Randall Centre for Cell and Molecular Biophysics, King's College London, Guy's Campus, London SE1 1UL, UK
| | - Elvira Infante
- Randall Centre for Cell and Molecular Biophysics, King's College London, Guy's Campus, London SE1 1UL, UK
| | - Dominic Alibhai
- Wolfson Bioimaging Facility, University of Bristol, Biomedical Sciences Building, University Walk, Bristol BS8 1TD, UK
| | - Felix Zhou
- Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX3 7DQ, UK
- Lyda Hill Department of Bioinformatics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Anne J. Ridley
- School of Cellular and Molecular Medicine, University of Bristol, Biomedical Sciences Building, University Walk, Bristol BS8 1TD, UK
- Randall Centre for Cell and Molecular Biophysics, King's College London, Guy's Campus, London SE1 1UL, UK
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2
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Multiple Genetic Loci Associated with Pug Dog Thoracolumbar Myelopathy. Genes (Basel) 2023; 14:genes14020385. [PMID: 36833311 PMCID: PMC9957375 DOI: 10.3390/genes14020385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 01/24/2023] [Accepted: 01/27/2023] [Indexed: 02/04/2023] Open
Abstract
Pug dogs with thoracolumbar myelopathy (PDM) present with a specific clinical phenotype that includes progressive pelvic limb ataxia and paresis, commonly accompanied by incontinence. Vertebral column malformations and lesions, excessive scar tissue of the meninges, and central nervous system inflammation have been described. PDM has a late onset and affects more male than female dogs. The breed-specific presentation of the disorder suggests that genetic risk factors are involved in the disease development. To perform a genome-wide search for PDM-associated loci, we applied a Bayesian model adapted for mapping complex traits (BayesR) and a cross-population extended haplotype homozygosity test (XP-EHH) in 51 affected and 38 control pugs. Nineteen associated loci (harboring 67 genes in total, including 34 potential candidate genes) and three candidate regions under selection (with four genes within or next to the signal) were identified. The multiple candidate genes identified have implicated functions in bone homeostasis, fibrotic scar tissue, inflammatory responses, or the formation, regulation, and differentiation of cartilage, suggesting the potential relevance of these processes to the pathogenesis of PDM.
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Gugnoni M, Manzotti G, Vitale E, Sauta E, Torricelli F, Reggiani F, Pistoni M, Piana S, Ciarrocchi A. OVOL2 impairs RHO GTPase signaling to restrain mitosis and aggressiveness of Anaplastic Thyroid Cancer. J Exp Clin Cancer Res 2022; 41:108. [PMID: 35337349 PMCID: PMC8957195 DOI: 10.1186/s13046-022-02316-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 03/08/2022] [Indexed: 11/10/2022] Open
Abstract
Background Anaplastic Thyroid Cancer (ATC) is an undifferentiated and aggressive tumor that often originates from well-Differentiated Thyroid Carcinoma (DTC) through a trans-differentiation process. Epithelial-to-Mesenchymal Transition (EMT) is recognized as one of the major players of this process. OVOL2 is a transcription factor (TF) that promotes epithelial differentiation and restrains EMT during embryonic development. OVOL2 loss in some types of cancers is linked to aggressiveness and poor prognosis. Here, we aim to clarify the unexplored role of OVOL2 in ATC. Methods Gene expression analysis in thyroid cancer patients and cell lines showed that OVOL2 is mainly associated with epithelial features and its expression is deeply impaired in ATC. To assess OVOL2 function, we established an OVOL2-overexpression model in ATC cell lines and evaluated its effects by analyzing gene expression, proliferation, invasion and migration abilities, cell cycle, specific protein localization through immunofluorescence staining. RNA-seq profiling showed that OVOL2 controls a complex network of genes converging on cell cycle and mitosis regulation and Chromatin Immunoprecipitation identified new OVOL2 target genes. Results Coherently with its reported function, OVOL2 re-expression restrained EMT and aggressiveness in ATC cells. Unexpectedly, we observed that it caused G2/M block, a consequent reduction in cell proliferation and an increase in cell death. This phenotype was associated to generalized abnormalities in the mitotic spindle structure and cytoskeletal organization. By RNA-seq experiments, we showed that many pathways related to cytoskeleton and migration, cell cycle and mitosis are profoundly affected by OVOL2 expression, in particular the RHO-GTPase pathway resulted as the most interesting. We demonstrated that RHO GTPase pathway is the central hub of OVOL2-mediated program in ATC and that OVOL2 transcriptionally inhibits RhoU and RhoJ. Silencing of RhoU recapitulated the OVOL2-driven phenotype pointing to this protein as a crucial target of OVOL2 in ATC. Conclusions Collectively, these data describe the role of OVOL2 in ATC and uncover a novel function of this TF in inhibiting the RHO GTPase pathway interlacing its effects on EMT, cytoskeleton dynamics and mitosis. Supplementary Information The online version contains supplementary material available at 10.1186/s13046-022-02316-2.
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Lou Y, Jiang Y, Liang Z, Liu B, Li T, Zhang D. Role of RhoC in cancer cell migration. Cancer Cell Int 2021; 21:527. [PMID: 34627249 PMCID: PMC8502390 DOI: 10.1186/s12935-021-02234-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 09/27/2021] [Indexed: 12/20/2022] Open
Abstract
Migration is one of the five major behaviors of cells. Although RhoC-a classic member of the Rho gene family-was first identified in 1985, functional RhoC data have only been widely reported in recent years. Cell migration involves highly complex signaling mechanisms, in which RhoC plays an essential role. Cell migration regulated by RhoC-of which the most well-known function is its role in cancer metastasis-has been widely reported in breast, gastric, colon, bladder, prostate, lung, pancreatic, liver, and other cancers. Our review describes the role of RhoC in various types of cell migration. The classic two-dimensional cell migration cycle constitutes cell polarization, adhesion regulation, cell contraction and tail retraction, most of which are modulated by RhoC. In the three-dimensional cell migration model, amoeboid migration is the most classic and well-studied model. Here, RhoC modulates the formation of membrane vesicles by regulating myosin II, thereby affecting the rate and persistence of amoeba-like migration. To the best of our knowledge, this review is the first to describe the role of RhoC in all cell migration processes. We believe that understanding the detail of RhoC-regulated migration processes will help us better comprehend the mechanism of cancer metastasis. This will contribute to the study of anti-metastatic treatment approaches, aiding in the identification of new intervention targets for therapeutic or genetic transformational purposes.
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Affiliation(s)
- Yingyue Lou
- Department of Plastic and Reconstructive Surgery, The First Hospital of Jilin University, Changchun, Jilin, China
| | - Yuhan Jiang
- Department of Plastic and Reconstructive Surgery, The First Hospital of Jilin University, Changchun, Jilin, China
| | - Zhen Liang
- Department of Neurology and Neuroscience Center, The First Hospital of Jilin University, Changchun, China
| | - Bingzhang Liu
- Department of Plastic and Reconstructive Surgery, The First Hospital of Jilin University, Changchun, Jilin, China
| | - Tian Li
- Department of Plastic and Reconstructive Surgery, The First Hospital of Jilin University, Changchun, Jilin, China.
| | - Duo Zhang
- Department of Plastic and Reconstructive Surgery, The First Hospital of Jilin University, Changchun, Jilin, China.
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Rehman S, Gora AH, Siriyappagouder P, Brugman S, Fernandes JMO, Dias J, Kiron V. Zebrafish intestinal transcriptome highlights subdued inflammatory responses to dietary soya bean and efficacy of yeast β-glucan. JOURNAL OF FISH DISEASES 2021; 44:1619-1637. [PMID: 34237181 DOI: 10.1111/jfd.13484] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 06/11/2021] [Accepted: 06/14/2021] [Indexed: 06/13/2023]
Abstract
Anti-nutritional factors in dietary components can have a negative impact on the intestinal barrier. Here, we present soya bean-induced changes in the intestine of juvenile zebrafish and the effect of yeast β-glucan through a transcriptomic approach. The inclusion of soya bean meal affected the expression of several intestinal barrier function-related genes like arl4ca, rab25b, rhoub, muc5ac, muc5d, clcn2c and cltb in zebrafish. Several metabolic genes like cyp2x10.2, cyp2aa2, aldh3a2b, crata, elovl4, elovl6, slc51a, gpat2 and ATP-dependent peptidase activity (lonrf, clpxb) were altered in the intestinal tissue. The expression of immune-related genes like nlrc3, nlrp12, gimap8, prdm1 and tph1a, and genes related to cell cycle, DNA damage and DNA repair (e.g. spo11, rad21l1, nabp1b, spata22, tdrd9) were also affected in the soya bean fed group. Furthermore, our study suggests the plausible effect of yeast β-glucan through the modulation of several genes that regulate immune responses and barrier integrity. Our findings indicate a subdued inflammation in juvenile zebrafish fed soya bean meal and the efficacy of β-glucan to counter these subtle inflammatory responses.
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Affiliation(s)
- Saima Rehman
- Faculty of Biosciences and Aquaculture, Nord University, Bodø, Norway
| | - Adnan H Gora
- Faculty of Biosciences and Aquaculture, Nord University, Bodø, Norway
| | | | - Sylvia Brugman
- Department of Animal Sciences, Wageningen University, Wageningen, The Netherlands
| | | | | | - Viswanath Kiron
- Faculty of Biosciences and Aquaculture, Nord University, Bodø, Norway
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6
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Zhang A, Aslam H, Sharma N, Warmflash A, Fakhouri WD. Conservation of Epithelial-to-Mesenchymal Transition Process in Neural Crest Cells and Metastatic Cancer. Cells Tissues Organs 2021; 210:151-172. [PMID: 34218225 DOI: 10.1159/000516466] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 04/12/2021] [Indexed: 11/19/2022] Open
Abstract
Epithelial to mesenchymal transition (EMT) is a highly conserved cellular process in several species, from worms to humans. EMT plays a fundamental role in early embryogenesis, wound healing, and cancer metastasis. For neural crest cell (NCC) development, EMT typically results in forming a migratory and potent cell population that generates a wide variety of cell and tissue, including cartilage, bone, connective tissue, endocrine cells, neurons, and glia amongst many others. The degree of conservation between the signaling pathways that regulate EMT during development and metastatic cancer (MC) has not been fully established, despite ample studies. This systematic review and meta-analysis dissects the major signaling pathways involved in EMT of NCC development and MC to unravel the similarities and differences. While the FGF, TGFβ/BMP, SHH, and NOTCH pathways have been rigorously investigated in both systems, the EGF, IGF, HIPPO, Factor Receptor Superfamily, and their intracellular signaling cascades need to be the focus of future NCC studies. In general, meta-analyses of the associated signaling pathways show a significant number of overlapping genes (particularly ligands, transcription regulators, and targeted cadherins) involved in each signaling pathway of both systems without stratification by body segments and cancer type. Lack of stratification makes it difficult to meaningfully evaluate the intracellular downstream effectors of each signaling pathway. Finally, pediatric neuroblastoma and melanoma are NCC-derived malignancies, which emphasize the importance of uncovering the EMT events that convert NCC into treatment-resistant malignant cells.
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Affiliation(s)
- April Zhang
- Center for Craniofacial Research, Department of Diagnostic and Biomedical Sciences, School of Dentistry, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Hira Aslam
- Center for Craniofacial Research, Department of Diagnostic and Biomedical Sciences, School of Dentistry, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Neha Sharma
- Center for Craniofacial Research, Department of Diagnostic and Biomedical Sciences, School of Dentistry, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Aryeh Warmflash
- Department of Biosciences, Rice University, Houston, Texas, USA
| | - Walid D Fakhouri
- Center for Craniofacial Research, Department of Diagnostic and Biomedical Sciences, School of Dentistry, University of Texas Health Science Center at Houston, Houston, Texas, USA.,Department of Pediatrics, McGovern Medical School, University of Texas Health Science Center, Houston, Texas, USA
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Gubar O, Croisé P, Kropyvko S, Gryaznova T, Tóth P, Blangy A, Vitale N, Rynditch A, Gasman S, Ory S. The atypical Rho GTPase RhoU interacts with intersectin-2 to regulate endosomal recycling pathways. J Cell Sci 2020; 133:jcs234104. [PMID: 32737221 DOI: 10.1242/jcs.234104] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 07/21/2020] [Indexed: 01/22/2023] Open
Abstract
Rho GTPases play a key role in various membrane trafficking processes. RhoU is an atypical small Rho GTPase related to Rac/Cdc42, which possesses unique N- and C-terminal domains that regulate its function and its subcellular localization. RhoU localizes at the plasma membrane, on endosomes and in cell adhesion structures where it governs cell signaling, differentiation and migration. However, despite its endomembrane localization, RhoU function in vesicular trafficking has been unexplored. Here, we identified intersectins (ITSNs) as new binding partners for RhoU and showed that the second PxxP motif at the N terminus of RhoU mediated interactions with the SH3 domains of ITSNs. To evaluate the function of RhoU and ITSNs in vesicular trafficking, we used fluorescent transferrin as a cargo for uptake experiments. We showed that silencing of either RhoU or ITSN2, but not ITSN1, increased transferrin accumulation in early endosomes, resulting from a defect in fast vesicle recycling. Concomitantly, RhoU and ITSN2 colocalized to a subset of Rab4-positive vesicles, suggesting that a RhoU-ITSN2 interaction may occur on fast recycling endosomes to regulate the fate of vesicular cargos.
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Affiliation(s)
- Olga Gubar
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, F-67000 Strasbourg, France
- Institute of Molecular Biology and Genetics NASU, 150 Zabolotnogo Street, Kyiv 03680, Ukraine
| | - Pauline Croisé
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, F-67000 Strasbourg, France
| | - Sergii Kropyvko
- Institute of Molecular Biology and Genetics NASU, 150 Zabolotnogo Street, Kyiv 03680, Ukraine
| | - Tetyana Gryaznova
- Institute of Molecular Biology and Genetics NASU, 150 Zabolotnogo Street, Kyiv 03680, Ukraine
| | - Petra Tóth
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, F-67000 Strasbourg, France
| | - Anne Blangy
- Centre de Recherche en Biologie Cellulaire de Montpellier (CRBM), Univ. Montpellier, CNRS, 34000 Montpellier, France
| | - Nicolas Vitale
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, F-67000 Strasbourg, France
| | - Alla Rynditch
- Institute of Molecular Biology and Genetics NASU, 150 Zabolotnogo Street, Kyiv 03680, Ukraine
| | - Stéphane Gasman
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, F-67000 Strasbourg, France
| | - Stéphane Ory
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, F-67000 Strasbourg, France
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Arraf AA, Yelin R, Reshef I, Jadon J, Abboud M, Zaher M, Schneider J, Vladimirov FK, Schultheiss TM. Hedgehog Signaling Regulates Epithelial Morphogenesis to Position the Ventral Embryonic Midline. Dev Cell 2020; 53:589-602.e6. [PMID: 32437643 DOI: 10.1016/j.devcel.2020.04.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2019] [Revised: 02/23/2020] [Accepted: 04/22/2020] [Indexed: 01/20/2023]
Abstract
Despite much progress toward understanding how epithelial morphogenesis is shaped by intra-epithelial processes including contractility, polarity, and adhesion, much less is known regarding how such cellular processes are coordinated by extra-epithelial signaling. During embryogenesis, the coelomic epithelia on the two sides of the chick embryo undergo symmetrical lengthening and thinning, converging medially to generate and position the dorsal mesentery (DM) in the embryonic midline. We find that Hedgehog signaling, acting through downstream effectors Sec5 (ExoC2), an exocyst complex component, and RhoU (Wrch-1), a small GTPase, regulates coelomic epithelium morphogenesis to guide DM midline positioning. These effects are accompanied by changes in epithelial cell-cell alignment and N-cadherin and laminin distribution, suggesting Hedgehog regulation of cell organization within the coelomic epithelium. These results indicate a role for Hedgehog signaling in regulating epithelial morphology and provide an example of how transcellular signaling can modulate specific cellular processes to shape tissue morphogenesis.
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Affiliation(s)
- Alaa A Arraf
- Department of Genetics and Developmental Biology, Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel
| | - Ronit Yelin
- Department of Genetics and Developmental Biology, Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel
| | - Inbar Reshef
- Department of Genetics and Developmental Biology, Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel
| | - Julian Jadon
- Department of Genetics and Developmental Biology, Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel
| | - Manar Abboud
- Department of Genetics and Developmental Biology, Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel
| | - Mira Zaher
- Department of Genetics and Developmental Biology, Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel
| | - Jenny Schneider
- Department of Genetics and Developmental Biology, Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel
| | - Fanny K Vladimirov
- Department of Genetics and Developmental Biology, Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel
| | - Thomas M Schultheiss
- Department of Genetics and Developmental Biology, Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel.
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9
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Hodge RG, Ridley AJ. Regulation and functions of RhoU and RhoV. Small GTPases 2020; 11:8-15. [PMID: 29189096 PMCID: PMC6959303 DOI: 10.1080/21541248.2017.1362495] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 07/26/2017] [Accepted: 07/28/2017] [Indexed: 01/01/2023] Open
Abstract
Rho GTPases play central roles in a wide variety of cellular processes, including cytoskeletal dynamics, cell adhesion and cell polarity. RhoU and RhoV are Rho GTPases that have some atypical properties compared with classical Rho family members, such as the presence of N- and C-terminal extension regions, unusual GDP/GTP cycling and post-translational modification by palmitoylation but not prenylation. Their activity and localization is regulated by the N-terminal and C-terminal regions, and so far no GEFs or GAPs have been identified for them. Similar to Rac and Cdc42, they interact with PAK serine/threonine kinases, and in the case of PAK4, this interaction leads to RhoU protein stabilization. In cells, RhoU and RhoV alter cell shape and cell adhesion, which probably underlies some of the phenotypes reported for these proteins in vivo, for example in heart development and epithelial morphogenesis. However, the molecular basis for these functions of RhoU and RhoV remains to be characterized.
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Affiliation(s)
- Richard G. Hodge
- Randall Division of Cell and Molecular Biophysics, King's College London, New Hunt's House, Guy's Campus, London, UK
| | - Anne J. Ridley
- Randall Division of Cell and Molecular Biophysics, King's College London, New Hunt's House, Guy's Campus, London, UK
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Laurin M, Gomez NC, Levorse J, Sendoel A, Sribour M, Fuchs E. An RNAi screen unravels the complexities of Rho GTPase networks in skin morphogenesis. eLife 2019; 8:e50226. [PMID: 31556874 PMCID: PMC6768663 DOI: 10.7554/elife.50226] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 09/24/2019] [Indexed: 01/09/2023] Open
Abstract
During mammalian embryogenesis, extensive cellular remodeling is needed for tissue morphogenesis. As effectors of cytoskeletal dynamics, Rho GTPases and their regulators are likely involved, but their daunting complexity has hindered progress in dissecting their functions. We overcome this hurdle by employing high throughput in utero RNAi-mediated screening to identify key Rho regulators of skin morphogenesis. Our screen unveiled hitherto unrecognized roles for Rho-mediated cytoskeletal remodeling events that impact hair follicle specification, differentiation, downgrowth and planar cell polarity. Coupling our top hit with gain/loss-of-function genetics, interactome proteomics and tissue imaging, we show that RHOU, an atypical Rho, governs the cytoskeletal-junction dynamics that establish columnar shape and planar cell polarity in epidermal progenitors. Conversely, RHOU downregulation is required to remodel to a conical cellular shape that enables hair bud invagination and downgrowth. Our findings underscore the power of coupling screens with proteomics to unravel the physiological significance of complex gene families.
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Affiliation(s)
- Melanie Laurin
- Robin Neustein Laboratory of Mammalian Cell Biology and DevelopmentHoward Hughes Medical Institute, The Rockefeller UniversityNew YorkUnited States
| | - Nicholas C Gomez
- Robin Neustein Laboratory of Mammalian Cell Biology and DevelopmentHoward Hughes Medical Institute, The Rockefeller UniversityNew YorkUnited States
| | - John Levorse
- Robin Neustein Laboratory of Mammalian Cell Biology and DevelopmentHoward Hughes Medical Institute, The Rockefeller UniversityNew YorkUnited States
| | - Ataman Sendoel
- Robin Neustein Laboratory of Mammalian Cell Biology and DevelopmentHoward Hughes Medical Institute, The Rockefeller UniversityNew YorkUnited States
| | - Megan Sribour
- Robin Neustein Laboratory of Mammalian Cell Biology and DevelopmentHoward Hughes Medical Institute, The Rockefeller UniversityNew YorkUnited States
| | - Elaine Fuchs
- Robin Neustein Laboratory of Mammalian Cell Biology and DevelopmentHoward Hughes Medical Institute, The Rockefeller UniversityNew YorkUnited States
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11
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Slaymi C, Vignal E, Crès G, Roux P, Blangy A, Raynaud P, Fort P. The atypical RhoU/Wrch1 Rho GTPase controls cell proliferation and apoptosis in the gut epithelium. Biol Cell 2019; 111:121-141. [PMID: 30834544 DOI: 10.1111/boc.201800062] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 01/07/2019] [Accepted: 02/07/2019] [Indexed: 01/07/2023]
Abstract
BACKGROUND The mammalian gut epithelium displays among the highest rates of self-renewal, with a turnover time of less than 5 days. Renewal involves concerted proliferation at the bottom of the crypt, migration and differentiation along the crypt-villus axis and anoïkis/shedding in the luminal epithelium. Renewal is controlled by interplay between signalling pathways, among which canonical and non-canonical Wnt signals play prominent roles. Overall 92% of colon tumours show increased canonical Wnt signalling resulting from mutations, established as major driver steps towards carcinogenesis. RESULTS Here, we examined the physiological role of RhoU/Wrch1 in gut homeostasis. RhoU is an atypical Rho GTPase related to Cdc42/Rac1 and identified as a transcriptional target of non-canonical Wnt signalling. We found that RHOU expression is reduced in human colorectal tumour samples. We show that RhoU is mainly expressed in the differentiated compartment of the gut epithelium. Rhou specific invalidation in the mouse gut elicits cell hyperplasia and is associated in the colon with a highly disorganized luminal epithelium. Hyperplasia affects all cell types in the small intestine and colon and has a higher impact on goblet cells. Hyperplasia is associated with a reduction of apoptosis and an increased proliferation. RhoU knockdown in human DLD-1 colon cancer cells also elicits a higher growth index and reduces cell apoptosis. Last, loss of RhoU function in the mouse gut epithelium or in DLD-1 cells increases RhoA activity and the level of phosphorylated Myosin Light Chain-2, which may functionally link RhoU activity to apoptosis. CONCLUSION RhoU is mostly expressed in the differentiated compartment of the gut. It plays a role in homeostasis as its specific invalidation elicits hyperplasia of all cell types. This mainly results from a reduction of apoptosis, through actomyosin-dependent mechanisms. SIGNIFICANCE RhoU negatively controls cell growth in the intestinal epithelium. Since its expression is sensitive to non-canonical Wnt signals and is reduced in colorectal tumours, downregulating RhoU may thus have an instrumental role in tumour progression.
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Affiliation(s)
- Chaker Slaymi
- CRBM, CNRS, University of Montpellier, 34293, Montpellier CEDEX 5, France
| | - Emmanuel Vignal
- CRBM, CNRS, University of Montpellier, 34293, Montpellier CEDEX 5, France
| | - Gaëlle Crès
- CRBM, CNRS, University of Montpellier, 34293, Montpellier CEDEX 5, France
| | - Pierre Roux
- CRBM, CNRS, University of Montpellier, 34293, Montpellier CEDEX 5, France
| | - Anne Blangy
- CRBM, CNRS, University of Montpellier, 34293, Montpellier CEDEX 5, France
| | - Peggy Raynaud
- CRBM, CNRS, University of Montpellier, 34293, Montpellier CEDEX 5, France
| | - Philippe Fort
- CRBM, CNRS, University of Montpellier, 34293, Montpellier CEDEX 5, France
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Alan JK, Robinson SK, Magsig KL, Demarco RS, Lundquist EA. The Atypical Rho GTPase CHW-1 Works with SAX-3/Robo To Mediate Axon Guidance in Caenorhabditis elegans. G3 (BETHESDA, MD.) 2018; 8:1885-1895. [PMID: 29653940 PMCID: PMC5982818 DOI: 10.1534/g3.118.200148] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 03/26/2018] [Indexed: 01/12/2023]
Abstract
During development, neuronal cells extend an axon toward their target destination in response to a cue to form a properly functioning nervous system. Rho proteins, Ras-related small GTPases that regulate cytoskeletal organization and dynamics, cell adhesion, and motility, are known to regulate axon guidance. Despite extensive knowledge about canonical Rho proteins (RhoA/Rac1/Cdc42), little is known about the Caenorhabditis elegans (C. elegans) atypical Cdc42-like family members CHW-1 and CRP-1 in regards to axon pathfinding and neuronal migration. chw-1(Chp/Wrch) encodes a protein that resembles human Chp (Wrch-2/RhoV) and Wrch-1 (RhoU), and crp-1 encodes for a protein that resembles TC10 and TCL. Here, we show that chw-1 works redundantly with crp-1 and cdc-42 in axon guidance. Furthermore, proper levels of chw-1 expression and activity are required for proper axon guidance. When examining CHW-1 GTPase mutants, we found that the native CHW-1 protein is likely partially activated, and mutations at a conserved residue (position 12 using Ras numbering, position 18 in CHW-1) alter axon guidance and neural migration. Additionally, we showed that chw-1 genetically interacts with the guidance receptor sax-3 in PDE neurons. Finally, in VD/DD motor neurons, chw-1 works downstream of sax-3 to control axon guidance. In summary, this is the first study implicating the atypical Rho GTPases chw-1 and crp-1 in axon guidance. Furthermore, this is the first evidence of genetic interaction between chw-1 and the guidance receptor sax-3 These data suggest that chw-1 is likely acting downstream and/or in parallel to sax-3 in axon guidance.
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Affiliation(s)
- Jamie K Alan
- Department of Pharmacology and Toxicology; Michigan State University; East Lansing, MI 48824
| | - Sara K Robinson
- College of Medicine; Central Michigan University; Mount Pleasant, MI 48859
| | - Katie L Magsig
- College of Medicine; Central Michigan University; Mount Pleasant, MI 48859
| | - Rafael S Demarco
- Department of Molecular Biosciences; University of Kansas; Lawrence, KS 60045
| | - Erik A Lundquist
- Department of Molecular Biosciences; University of Kansas; Lawrence, KS 60045
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13
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Juszczak GR, Stankiewicz AM. Glucocorticoids, genes and brain function. Prog Neuropsychopharmacol Biol Psychiatry 2018; 82:136-168. [PMID: 29180230 DOI: 10.1016/j.pnpbp.2017.11.020] [Citation(s) in RCA: 82] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Revised: 10/18/2017] [Accepted: 11/23/2017] [Indexed: 01/02/2023]
Abstract
The identification of key genes in transcriptomic data constitutes a huge challenge. Our review of microarray reports revealed 88 genes whose transcription is consistently regulated by glucocorticoids (GCs), such as cortisol, corticosterone and dexamethasone, in the brain. Replicable transcriptomic data were combined with biochemical and physiological data to create an integrated view of the effects induced by GCs. The most frequently reported genes were Errfi1 and Ddit4. Their up-regulation was associated with the altered transcription of genes regulating growth factor and mTORC1 signaling (Gab1, Tsc22d3, Dusp1, Ndrg2, Ppp5c and Sesn1) and progression of the cell cycle (Ccnd1, Cdkn1a and Cables1). The GC-induced reprogramming of cell function involves changes in the mRNA level of genes responsible for the regulation of transcription (Klf9, Bcl6, Klf15, Tle3, Cxxc5, Litaf, Tle4, Jun, Sox4, Sox2, Sox9, Irf1, Sall2, Nfkbia and Id1) and the selective degradation of mRNA (Tob2). Other genes are involved in the regulation of metabolism (Gpd1, Aldoc and Pdk4), actin cytoskeleton (Myh2, Nedd9, Mical2, Rhou, Arl4d, Osbpl3, Arhgef3, Sdc4, Rdx, Wipf3, Chst1 and Hepacam), autophagy (Eva1a and Plekhf1), vesicular transport (Rhob, Ehd3, Vps37b and Scamp2), gap junctions (Gjb6), immune response (Tiparp, Mertk, Lyve1 and Il6r), signaling mediated by thyroid hormones (Thra and Sult1a1), calcium (Calm2), adrenaline/noradrenaline (Adcy9 and Adra1d), neuropeptide Y (Npy1r) and histamine (Hdc). GCs also affected genes involved in the synthesis of polyamines (Azin1) and taurine (Cdo1). The actions of GCs are restrained by feedback mechanisms depending on the transcription of Sgk1, Fkbp5 and Nr3c1. A side effect induced by GCs is increased production of reactive oxygen species. Available data show that the brain's response to GCs is part of an emergency mode characterized by inactivation of non-core activities, restrained inflammation, restriction of investments (growth), improved efficiency of energy production and the removal of unnecessary or malfunctioning cellular components to conserve energy and maintain nutrient supply during the stress response.
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Affiliation(s)
- Grzegorz R Juszczak
- Department of Animal Behavior, Institute of Genetics and Animal Breeding, Jastrzebiec, ul. Postepu 36A, 05-552 Magdalenka, Poland.
| | - Adrian M Stankiewicz
- Department of Molecular Biology, Institute of Genetics and Animal Breeding, Jastrzebiec, ul. Postepu 36A, 05-552 Magdalenka, Poland
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14
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Canovas Nunes S, Manzoni M, Pizzi M, Mandato E, Carrino M, Quotti Tubi L, Zambello R, Adami F, Visentin A, Barilà G, Trentin L, Manni S, Neri A, Semenzato G, Piazza F. The small GTPase RhoU lays downstream of JAK/STAT signaling and mediates cell migration in multiple myeloma. Blood Cancer J 2018; 8:20. [PMID: 29440639 PMCID: PMC5811530 DOI: 10.1038/s41408-018-0053-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Revised: 12/19/2017] [Accepted: 01/08/2018] [Indexed: 12/22/2022] Open
Abstract
Multiple myeloma is a post-germinal center B-cell neoplasm, characterized by the proliferation of malignant bone marrow plasma cells, whose survival and proliferation is sustained by growth factors and cytokines present in the bone marrow microenvironment. Among them, IL-6 triggers the signal downstream of its receptor, leading to the activation of the JAK/STAT pathway. The atypical GTPase RhoU lays downstream of STAT3 transcription factor and could be responsible for mediating its effects on cytoskeleton dynamics. Here we demonstrate that RHOU is heterogeneously expressed in primary multiple myeloma cells and significantly modulated with disease progression. At the mRNA level, RHOU expression in myeloma patients correlated with the expression of STAT3 and its targets MIR21 and SOCS3. Also, IL-6 stimulation of human myeloma cell lines up-regulated RHOU through STAT3 activation. On the other hand, RhoU silencing led to a decrease in cell migration with the accumulation of actin stress fibers, together with a decrease in cyclin D2 expression and in cell cycle progression. Furthermore, we found that even though lenalidomide positively regulated RhoU expression leading to higher cell migration rates, it actually led to cell cycle arrest probably through a p21 dependent mechanism. Lenalidomide treatment in combination with RhoU silencing determined a loss of cytoskeletal organization inhibiting cell migration, and a further increase in the percentage of cells in a resting phase. These results unravel a role for RhoU not only in regulating the migratory features of malignant plasma cells, but also in controlling cell cycle progression.
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Affiliation(s)
- Sara Canovas Nunes
- Department of Medicine, Division of Hematology, University of Padova, Padova, Italy.,Laboratory of Normal and Malignant Hematopoiesis, Venetian Institute of Molecular Medicine, Padova, Italy
| | - Martina Manzoni
- Hematology Unit, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy.,Department of Oncology and Hemato-Oncology, University of Milano, Milano, Italy
| | - Marco Pizzi
- Surgical Pathology and Cytopathology Unit, Department of Medicine - DIMED, University of Padova, Padova, Italy
| | - Elisa Mandato
- Department of Medicine, Division of Hematology, University of Padova, Padova, Italy.,Laboratory of Normal and Malignant Hematopoiesis, Venetian Institute of Molecular Medicine, Padova, Italy.,Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Marilena Carrino
- Department of Medicine, Division of Hematology, University of Padova, Padova, Italy.,Laboratory of Normal and Malignant Hematopoiesis, Venetian Institute of Molecular Medicine, Padova, Italy
| | - Laura Quotti Tubi
- Department of Medicine, Division of Hematology, University of Padova, Padova, Italy.,Laboratory of Normal and Malignant Hematopoiesis, Venetian Institute of Molecular Medicine, Padova, Italy
| | - Renato Zambello
- Department of Medicine, Division of Hematology, University of Padova, Padova, Italy.,Laboratory of Normal and Malignant Hematopoiesis, Venetian Institute of Molecular Medicine, Padova, Italy
| | - Fausto Adami
- Department of Medicine, Division of Hematology, University of Padova, Padova, Italy
| | - Andrea Visentin
- Department of Medicine, Division of Hematology, University of Padova, Padova, Italy
| | - Gregorio Barilà
- Department of Medicine, Division of Hematology, University of Padova, Padova, Italy
| | - Livio Trentin
- Department of Medicine, Division of Hematology, University of Padova, Padova, Italy.,Laboratory of Normal and Malignant Hematopoiesis, Venetian Institute of Molecular Medicine, Padova, Italy
| | - Sabrina Manni
- Department of Medicine, Division of Hematology, University of Padova, Padova, Italy.,Laboratory of Normal and Malignant Hematopoiesis, Venetian Institute of Molecular Medicine, Padova, Italy
| | - Antonino Neri
- Hematology Unit, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy.,Department of Oncology and Hemato-Oncology, University of Milano, Milano, Italy
| | - Gianpietro Semenzato
- Department of Medicine, Division of Hematology, University of Padova, Padova, Italy.,Laboratory of Normal and Malignant Hematopoiesis, Venetian Institute of Molecular Medicine, Padova, Italy
| | - Francesco Piazza
- Department of Medicine, Division of Hematology, University of Padova, Padova, Italy. .,Laboratory of Normal and Malignant Hematopoiesis, Venetian Institute of Molecular Medicine, Padova, Italy.
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15
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JMJD3 and NF-κB-dependent activation of Notch1 gene is required for keratinocyte migration during skin wound healing. Sci Rep 2017; 7:6494. [PMID: 28747631 PMCID: PMC5529578 DOI: 10.1038/s41598-017-06750-7] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Accepted: 06/16/2017] [Indexed: 12/18/2022] Open
Abstract
It has been shown that epigenetic regulation plays an important role in skin wound healing. We previously found that histone H3K27me3 demethylase JMJD3 regulates inflammation and cell migration in keratinocyte wound healing. In this study, we identified Notch1 as a direct target of JMJD3 and NF-κB in wounded keratinocytes using in vitro cell and in vivo animal models. We found that Notch1 is up-regulated in the wound edge and its expression is dependent on JMJD3 and NF-κB in wounded keratinocytes. We also found that Notch1 activates the expression of RhoU and PLAU gene, which are critical regulators of cell migration. Consistently, depletion or inactivation of Notch1 resulted in decreased filopodia formation, increased focal adhesion and actin stress fiber, leading to reduced keratinocyte migration and skin wound healing. Thus, our findings provide the molecular mechanism involving JMJD3/NF-κB-Notch pathway in keratinocyte wound healing.
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16
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Dart AE, Box GM, Court W, Gale ME, Brown JP, Pinder SE, Eccles SA, Wells CM. PAK4 promotes kinase-independent stabilization of RhoU to modulate cell adhesion. J Cell Biol 2016; 211:863-79. [PMID: 26598620 PMCID: PMC4657161 DOI: 10.1083/jcb.201501072] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
PAK4, via a novel kinase-independent mechanism, protects RhoU from a Rab40A/Cullin 5 ubiquitin ligase complex–driven K48 ubiquitination to regulate breast cancer cell adhesion. P21-activated kinase 4 (PAK4) is a Cdc42 effector protein thought to regulate cell adhesion disassembly in a kinase-dependent manner. We found that PAK4 expression is significantly higher in high-grade human breast cancer patient samples, whereas depletion of PAK4 modifies cell adhesion dynamics of breast cancer cells. Surprisingly, systematic analysis of PAK4 functionality revealed that PAK4-driven adhesion turnover is neither dependent on Cdc42 binding nor kinase activity. Rather, reduced expression of PAK4 leads to a concomitant loss of RhoU expression. We report that RhoU is targeted for ubiquitination by the Rab40A–Cullin 5 complex and demonstrate that PAK4 protects RhoU from ubiquitination in a kinase-independent manner. Overexpression of RhoU rescues the PAK4 depletion phenotype, whereas loss of RhoU expression reduces cell adhesion turnover and migration. These data support a new kinase-independent mechanism for PAK4 function, where an important role of PAK4 in cellular adhesions is to stabilize RhoU protein levels. Thus, PAK4 and RhoU cooperate to drive adhesion turnover and promote cell migration.
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Affiliation(s)
- Anna E Dart
- Division of Cancer Studies, King's College London, London SE1 1UL, England, UK
| | - Gary M Box
- Tumour Biology and Metastasis, Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London SM2 5NG, England, UK
| | - William Court
- Tumour Biology and Metastasis, Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London SM2 5NG, England, UK
| | - Madeline E Gale
- Division of Cancer Studies, King's College London, London SE1 1UL, England, UK
| | - John P Brown
- Breast Research Pathology, Department of Research Oncology, Division of Cancer Studies, School of Medicine, Guy's Hospital, King's College London, London SE1 9RT, England, UK
| | - Sarah E Pinder
- Breast Research Pathology, Department of Research Oncology, Division of Cancer Studies, School of Medicine, Guy's Hospital, King's College London, London SE1 9RT, England, UK
| | - Suzanne A Eccles
- Tumour Biology and Metastasis, Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London SM2 5NG, England, UK
| | - Claire M Wells
- Division of Cancer Studies, King's College London, London SE1 1UL, England, UK
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17
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Abstract
This review addresses the developmental roles of 2 GTPases of the Rho family, RhoV/Chp and RhoU/Wrch. These two GTPases form a distinct subfamily related to Rac and Cdc42 proteins and were detected in a screen for Rho members that are particularly expressed in the neural crest, an embryonic tissue peculiar to vertebrates. The neural crest represents a physiological model of normal epithelial to mesenchymal transition (EMT), in which epithelial cells at the border of neural and non-neural ectoderm differentiate, lose their intercellular connections and migrate throughout the embryo. We showed that RhoV, transiently induced by the canonical Wnt pathway, is required for the full differentiation of neural crest cells, while RhoU, induced later by the non-canonical Wnt pathway, is necessary for the migration process. These two GTPases, which are highly conserved across vertebrates, are thus tightly functionally linked to Wnt signaling, whose implication in embryonic development and cancer progression is well established. In the light of the recent literature, we discuss how RhoV and RhoU may achieve their physiological functions.
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Affiliation(s)
- Sandrine Faure
- a Universités Montpellier 2 et 1; CRBM; UMS BioCampus ; Montpellier , France.,b INSERM ; Montpellier , France
| | - Philippe Fort
- a Universités Montpellier 2 et 1; CRBM; UMS BioCampus ; Montpellier , France.,c CNRS UMR 5237 ; Montpellier , France
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18
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Vuong LM, Chellappa K, Dhahbi JM, Deans JR, Fang B, Bolotin E, Titova NV, Hoverter NP, Spindler SR, Waterman ML, Sladek FM. Differential Effects of Hepatocyte Nuclear Factor 4α Isoforms on Tumor Growth and T-Cell Factor 4/AP-1 Interactions in Human Colorectal Cancer Cells. Mol Cell Biol 2015; 35:3471-90. [PMID: 26240283 PMCID: PMC4573706 DOI: 10.1128/mcb.00030-15] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Revised: 02/04/2015] [Accepted: 07/07/2015] [Indexed: 12/18/2022] Open
Abstract
The nuclear receptor hepatocyte nuclear factor 4α (HNF4α) is tumor suppressive in the liver but amplified in colon cancer, suggesting that it also might be oncogenic. To investigate whether this discrepancy is due to different HNF4α isoforms derived from its two promoters (P1 and P2), we generated Tet-On-inducible human colon cancer (HCT116) cell lines that express either the P1-driven (HNF4α2) or P2-driven (HNF4α8) isoform and analyzed them for tumor growth and global changes in gene expression (transcriptome sequencing [RNA-seq] and chromatin immunoprecipitation sequencing [ChIP-seq]). The results show that while HNF4α2 acts as a tumor suppressor in the HCT116 tumor xenograft model, HNF4α8 does not. Each isoform regulates the expression of distinct sets of genes and recruits, colocalizes, and competes in a distinct fashion with the Wnt/β-catenin mediator T-cell factor 4 (TCF4) at CTTTG motifs as well as at AP-1 motifs (TGAXTCA). Protein binding microarrays (PBMs) show that HNF4α and TCF4 share some but not all binding motifs and that single nucleotide polymorphisms (SNPs) in sites bound by both HNF4α and TCF4 can alter binding affinity in vitro, suggesting that they could play a role in cancer susceptibility in vivo. Thus, the HNF4α isoforms play distinct roles in colon cancer, which could be due to differential interactions with the Wnt/β-catenin/TCF4 and AP-1 pathways.
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Affiliation(s)
- Linh M Vuong
- Department of Cell Biology and Neuroscience, University of California, Riverside, Riverside, California, USA
| | - Karthikeyani Chellappa
- Department of Cell Biology and Neuroscience, University of California, Riverside, Riverside, California, USA
| | - Joseph M Dhahbi
- Department of Biochemistry, University of California, Riverside, Riverside, California, USA
| | - Jonathan R Deans
- Department of Cell Biology and Neuroscience, University of California, Riverside, Riverside, California, USA
| | - Bin Fang
- Department of Cell Biology and Neuroscience, University of California, Riverside, Riverside, California, USA
| | - Eugene Bolotin
- Department of Cell Biology and Neuroscience, University of California, Riverside, Riverside, California, USA
| | - Nina V Titova
- Department of Cell Biology and Neuroscience, University of California, Riverside, Riverside, California, USA
| | - Nate P Hoverter
- Department of Microbiology and Molecular Genetics, University of California, Irvine, Irvine, California, USA
| | - Stephen R Spindler
- Department of Biochemistry, University of California, Riverside, Riverside, California, USA
| | - Marian L Waterman
- Department of Microbiology and Molecular Genetics, University of California, Irvine, Irvine, California, USA
| | - Frances M Sladek
- Department of Cell Biology and Neuroscience, University of California, Riverside, Riverside, California, USA
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19
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Abstract
This review addresses the developmental roles of two GTPases of the Rho family, RhoV/Chp and RhoU/Wrch. These two GTPases form a distinct subfamily related to Rac and Cdc42 proteins and were detected in a screen for Rho members that are particularly expressed in the neural crest, an embryonic tissue peculiar to vertebrates. The neural crest represents a physiological model of normal epithelial to mesenchymal transition (EMT), in which epithelial cells at the border of neural and non-neural ectoderm differentiate, lose their intercellular connections and migrate throughout the embryo. We showed that RhoV, transiently induced by the canonical Wnt pathway, is required for the full differentiation of neural crest cells, while RhoU, induced later by the non-canonical Wnt pathway, is necessary for the migration process. These two GTPases, which are highly conserved across vertebrates, are thus tightly functionally linked to Wnt signaling, whose implication in embryonic development and cancer progression is well established. In the light of the recent literature, we discuss how RhoV and RhoU may achieve their physiological functions.
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20
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Schmid D, Zeis T, Sobrio M, Schaeren-Wiemers N. MAL overexpression leads to disturbed expression of genes that influence cytoskeletal organization and differentiation of Schwann cells. ASN Neuro 2014; 6:1759091414548916. [PMID: 25290060 PMCID: PMC4187015 DOI: 10.1177/1759091414548916] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
In the developing peripheral nervous system, a coordinated reciprocal signaling between Schwann cells and axons is crucial for accurate myelination. The myelin and lymphocyte protein MAL is a component of lipid rafts that is important for targeting proteins and lipids to distinct domains. MAL overexpression impedes peripheral myelinogenesis, which is evident by a delayed onset of myelination and reduced expression of the myelin protein zero (Mpz/P0) and the low-affinity neurotrophin receptor p75(NTR). This study shows that MAL overexpression leads to a significant reduction of Mpz and p75(NTR) expression in primary mouse Schwann cell cultures, which was already evident before differentiation, implicating an effect of MAL in early Schwann cell development. Their transcription was robustly reduced, despite normal expression of essential transcription factors and receptors. Further, the cAMP response element-binding protein (CREB) and phosphoinositide 3-kinase signaling pathways important for Schwann cell differentiation were correctly induced, highlighting that other so far unknown rate limiting factors do exist. We identified novel genes expressed by Schwann cells in a MAL-dependent manner in vivo and in vitro. A number of those, including S100a4, RhoU and Krt23, are implicated in cytoskeletal organization and plasma membrane dynamics. We showed that S100a4 is predominantly expressed by nonmyelinating Schwann cells, whereas RhoU was localized within myelin membranes, and Krt23 was detected in nonmyelinating as well as in myelinating Schwann cells. Their differential expression during early peripheral nerve development further underlines their possible role in influencing Schwann cell differentiation and myelination.
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Affiliation(s)
- Daniela Schmid
- Department of Biomedicine, University Hospital Basel, University of Basel, Switzerland
| | - Thomas Zeis
- Department of Biomedicine, University Hospital Basel, University of Basel, Switzerland
| | - Monia Sobrio
- Department of Biomedicine, University Hospital Basel, University of Basel, Switzerland
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21
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Sadok A, Marshall CJ. Rho GTPases: masters of cell migration. Small GTPases 2014; 5:e29710. [PMID: 24978113 PMCID: PMC4107589 DOI: 10.4161/sgtp.29710] [Citation(s) in RCA: 158] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Revised: 06/06/2014] [Accepted: 06/24/2014] [Indexed: 12/17/2022] Open
Abstract
Since their discovery in the late eighties, the role of Rho GTPases in the regulation of cell migration has been extensively studied and has mainly focused on the hallmark family members Rho, Rac, and Cdc42. Recent technological advances in cell biology, such as Rho-family GTPase activity biosensors, studies in 3D, and unbiased RNAi-based screens, have revealed an increasingly complex role for Rho GTPases during cell migration, with many inter-connected functions and a strong dependency on the physical and chemical properties of the surrounding environment. This review aims to give an overview of recent studies on the role of Rho-family GTPase members in the modulation of cell migration in different environments, and discuss future directions.
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Affiliation(s)
- Amine Sadok
- The Institute of Cancer Research; Division of Cancer Biology; London, UK
| | - Chris J Marshall
- The Institute of Cancer Research; Division of Cancer Biology; London, UK
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22
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STAT3 Target Genes Relevant to Human Cancers. Cancers (Basel) 2014; 6:897-925. [PMID: 24743777 PMCID: PMC4074809 DOI: 10.3390/cancers6020897] [Citation(s) in RCA: 365] [Impact Index Per Article: 36.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2014] [Revised: 03/22/2014] [Accepted: 03/28/2014] [Indexed: 12/29/2022] Open
Abstract
Since its discovery, the STAT3 transcription factor has been extensively studied for its function as a transcriptional regulator and its role as a mediator of development, normal physiology, and pathology of many diseases, including cancers. These efforts have uncovered an array of genes that can be positively and negatively regulated by STAT3, alone and in cooperation with other transcription factors. Through regulating gene expression, STAT3 has been demonstrated to play a pivotal role in many cellular processes including oncogenesis, tumor growth and progression, and stemness. Interestingly, recent studies suggest that STAT3 may behave as a tumor suppressor by activating expression of genes known to inhibit tumorigenesis. Additional evidence suggested that STAT3 may elicit opposing effects depending on cellular context and tumor types. These mixed results signify the need for a deeper understanding of STAT3, including its upstream regulators, parallel transcription co-regulators, and downstream target genes. To help facilitate fulfilling this unmet need, this review will be primarily focused on STAT3 downstream target genes that have been validated to associate with tumorigenesis and/or malignant biology of human cancers.
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23
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Fort P, Théveneau E. PleiotRHOpic: Rho pathways are essential for all stages of Neural Crest development. Small GTPases 2014; 5:e27975. [PMID: 24614304 DOI: 10.4161/sgtp.27975] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Neural Crest (NC) cells are a multipotent migratory stem cell population unique to vertebrates, which contributes extensively to the formation of a wide array of neural and non-neural structures in the embryo. NC cells originate in the ectoderm at the border of the neural tube, undergo an epithelial-mesenchymal transition and acquire outstanding individual and collective migratory properties that allow them to disseminate and differentiate to different parts of the body. This exquisite capacity to switch from an epithelium to motile cells represents both a puzzling biological issue and an attractive model to address the basic mechanisms of cell migration and their alteration during cancer progression. Here we review how signaling pathways controlled by Rho GTPases, key players in cell adhesion, contraction, migration and polarity, contribute to the control the different phases of NC development.
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Affiliation(s)
- Philippe Fort
- CNRS; University Montpellier 2; CRBM-UMR5237; Montpellier, France
| | - Eric Théveneau
- CNRS; University Toulouse III; Centre de Biologie du Développement; UMR5547; Toulouse, France
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24
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Bhavsar PJ, Infante E, Khwaja A, Ridley AJ. Analysis of Rho GTPase expression in T-ALL identifies RhoU as a target for Notch involved in T-ALL cell migration. Oncogene 2013; 32:198-208. [PMID: 22349824 PMCID: PMC3378627 DOI: 10.1038/onc.2012.42] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2011] [Revised: 01/06/2012] [Accepted: 01/06/2012] [Indexed: 01/04/2023]
Abstract
NOTCH1 is frequently mutated in T-cell acute lymphoblastic leukaemia (T-ALL), and can stimulate T-ALL cell survival and proliferation. Here we explore the hypothesis that Notch1 also alters T-ALL cell migration. Rho GTPases are well known to regulate cell adhesion and migration. We have analysed the expression levels of Rho GTPases in primary T-ALL samples compared with normal T cells by quantitative PCR. We found that 5 of the 20 human Rho genes are highly and consistently upregulated in T-ALL, and 3 further Rho genes are expressed in T-ALL but not detectable in normal T cells. Of these, RHOU expression is highly correlated with the expression of the Notch1 target DELTEX-1. Inhibition of Notch1 signalling with a γ-secretase inhibitor (GSI) or Notch1 RNA interference reduced RhoU expression in T-ALL cells, whereas constitutively active Notch1 increased RhoU expression. In addition, Notch1 or RhoU depletion, or GSI treatment, inhibits T-ALL cell adhesion, migration and chemotaxis. These results indicate that NOTCH1 mutation stimulates T-ALL cell migration through RhoU upregulation that could contribute to the leukaemia cell dissemination.
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Affiliation(s)
- Parag J. Bhavsar
- Randall Division of Cell and Molecular Biophysics, King’s College London, New Hunt’s House, Guy’s Campus, London SE1 1UL, UK
| | - Elvira Infante
- Randall Division of Cell and Molecular Biophysics, King’s College London, New Hunt’s House, Guy’s Campus, London SE1 1UL, UK
- National Institute for Health Research (NIHR), Biomedical Research Centre, Guy’s and St Thomas’ NHS and King’s College London, London, UK
| | - Asim Khwaja
- UCL Cancer Institute, University College London, London, UK
| | - Anne J. Ridley
- Randall Division of Cell and Molecular Biophysics, King’s College London, New Hunt’s House, Guy’s Campus, London SE1 1UL, UK
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Simpson JC, Joggerst B, Laketa V, Verissimo F, Cetin C, Erfle H, Bexiga MG, Singan VR, Hériché JK, Neumann B, Mateos A, Blake J, Bechtel S, Benes V, Wiemann S, Ellenberg J, Pepperkok R. Genome-wide RNAi screening identifies human proteins with a regulatory function in the early secretory pathway. Nat Cell Biol 2012; 14:764-74. [DOI: 10.1038/ncb2510] [Citation(s) in RCA: 154] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2012] [Accepted: 04/26/2012] [Indexed: 02/06/2023]
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Ory S, Brazier H, Blangy A. Identification of a bipartite focal adhesion localization signal in RhoU/Wrch-1, a Rho family GTPase that regulates cell adhesion and migration. Biol Cell 2012; 99:701-16. [PMID: 17620058 DOI: 10.1042/bc20070058] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
BACKGROUND INFORMATION Rho GTPases are important regulators of cytoskeleton dynamics and cell adhesion. RhoU/Wrch-1 is a Rho GTPase which shares sequence similarities with Rac1 and Cdc42 (cell division cycle 42), but has also extended N- and C-terminal domains. The N-terminal extension promotes binding to SH3 (Src homology 3)-domain-containing adaptors, whereas the C-terminal extension mediates membrane targeting through palmitoylation of its non-conventional CAAX box. RhoU/Wrch-1 possesses transforming activity, which is negatively regulated by its N-terminal extension and depends on palmitoylation. RESULTS In the present study, we have shown that RhoU is localized to podosomes in osteoclasts and c-Src-expressing cells, and to focal adhesions of HeLa cells and fibroblasts. The N-terminal extension and the palmitoylation site were dispensable, whereas the C-terminal extension and effector binding loop were critical for RhoU targeting to focal adhesions. Moreover, the number of focal adhesions was reduced and their distribution changed upon expression of activated RhoU. Conversely, RhoU silencing increased the number of focal adhesions. As RhoU was only transiently associated with adhesion structures, this suggests that RhoU may modify adhesion turnover and cell migration rate. Indeed, we found that migration distances were increased in cells expressing activated RhoU and decreased when RhoU was knocked-down. CONCLUSIONS Our data indicate that RhoU localizes to adhesion structures, regulates their number and distribution and increases cell motility. It also suggests that the RhoU effector binding and C-terminal domains are critical for these functions.
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Affiliation(s)
- Stéphane Ory
- CRBM CNRS UMR5237, 1919 route de Mende, 34293 Montpellier cedex 5, France
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Invadosome regulation by adhesion signaling. Curr Opin Cell Biol 2011; 23:597-606. [DOI: 10.1016/j.ceb.2011.04.002] [Citation(s) in RCA: 110] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2011] [Revised: 04/11/2011] [Accepted: 04/11/2011] [Indexed: 12/16/2022]
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Loebel DAF, Studdert JB, Power M, Radziewic T, Jones V, Coultas L, Jackson Y, Rao RS, Steiner K, Fossat N, Robb L, Tam PPL. Rhou maintains the epithelial architecture and facilitates differentiation of the foregut endoderm. Development 2011; 138:4511-22. [PMID: 21903671 DOI: 10.1242/dev.063867] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Rhou encodes a Cdc42-related atypical Rho GTPase that influences actin organization in cultured cells. In mouse embryos at early-somite to early-organogenesis stages, Rhou is expressed in the columnar endoderm epithelium lining the lateral and ventral wall of the anterior intestinal portal. During foregut development, Rhou is downregulated in regions where the epithelium acquires a multilayered morphology heralding the budding of organ primordia. In embryos generated from Rhou knockdown embryonic stem (ES) cells, the embryonic foregut displays an abnormally flattened shape. The epithelial architecture of the endoderm is disrupted, the cells are depleted of microvilli and the phalloidin-stained F-actin content of their sub-apical cortical domain is reduced. Rhou-deficient cells in ES cell-derived embryos and embryoid bodies are less efficient in endoderm differentiation. Impaired endoderm differentiation of Rhou-deficient ES cells is accompanied by reduced expression of c-Jun/AP-1 target genes, consistent with a role for Rhou in regulating JNK activity. Downregulation of Rhou in individual endoderm cells results in a reduced ability of these cells to occupy the apical territory of the epithelium. Our findings highlight epithelial morphogenesis as a required intermediate step in the differentiation of endoderm progenitors. In vivo, Rhou activity maintains the epithelial architecture of the endoderm progenitors, and its downregulation accompanies the transition of the columnar epithelium in the embryonic foregut to a multilayered cell sheet during organ formation.
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Affiliation(s)
- David A F Loebel
- Embryology Unit, Children's Medical Research Institute, Westmead, NSW 2145, Australia
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Identification and characterization of a set of conserved and new regulators of cytoskeletal organization, cell morphology and migration. BMC Biol 2011; 9:54. [PMID: 21834987 PMCID: PMC3201212 DOI: 10.1186/1741-7007-9-54] [Citation(s) in RCA: 131] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2011] [Accepted: 08/11/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Cell migration is essential during development and in human disease progression including cancer. Most cell migration studies concentrate on known or predicted components of migration pathways. RESULTS Here we use data from a genome-wide RNAi morphology screen in Drosophila melanogaster cells together with bioinformatics to identify 26 new regulators of morphology and cytoskeletal organization in human cells. These include genes previously implicated in a wide range of functions, from mental retardation, Down syndrome and Huntington's disease to RNA and DNA-binding genes. We classify these genes into seven groups according to phenotype and identify those that affect cell migration. We further characterize a subset of seven genes, FAM40A, FAM40B, ARC, FMNL3, FNBP3/FBP11, LIMD1 and ZRANB1, each of which has a different effect on cell shape, actin filament distribution and cell migration. Interestingly, in several instances closely related isoforms with a single Drosophila homologue have distinct phenotypes. For example, FAM40B depletion induces cell elongation and tail retraction defects, whereas FAM40A depletion reduces cell spreading. CONCLUSIONS Our results identify multiple regulators of cell migration and cytoskeletal signalling that are highly conserved between Drosophila and humans, and show that closely related paralogues can have very different functions in these processes.
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ARHGAP30 is a Wrch-1-interacting protein involved in actin dynamics and cell adhesion. Biochem Biophys Res Commun 2011; 409:96-102. [DOI: 10.1016/j.bbrc.2011.04.116] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2011] [Accepted: 04/24/2011] [Indexed: 11/23/2022]
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31
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Zhang JS, Koenig A, Young C, Billadeau DD. GRB2 couples RhoU to epidermal growth factor receptor signaling and cell migration. Mol Biol Cell 2011; 22:2119-30. [PMID: 21508312 PMCID: PMC3113775 DOI: 10.1091/mbc.e10-12-0969] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
RhoU, an atypical Rho family member with unique N- and C-terminal extensions, associates with activated EGFR in a GRB2-dependent manner via its N-terminal proline-rich motifs and is integrated into EGFR-mediated signaling, leading to AP1 transcriptional activity and cell migration. RhoU is an atypical Rho family member with high homology to CDC42 but containing unique N- and C-terminal extensions. The mechanisms regulating RhoU activation, as well as its downstream effectors, are not fully characterized. We show that after epidermal growth factor (EGF) stimulation RhoU colocalizes with EGF receptor (EGFR) on endosomes, which requires both its N- and C-terminal extension sequences. Moreover, RhoU physically associates with activated EGFR in a GRB2-dependent manner through specific proline-rich motifs within its N-terminus. Mutation of these proline-rich sequences or suppression of GRB2 by RNA interference abrogates the interaction of RhoU with activated EGFR, as well as EGF-stimulated RhoU GTP binding. In addition, RhoU is involved in EGFR-mediated signaling, leading to AP1 transcriptional activity and cell migration in pancreatic cancer cells, events that require its interaction with the Grb2–EGFR complex. Taken together, the data suggest a unique regulatory mechanism by which RhoU interaction with SH3 adaptor proteins might serve to integrate growth factor receptor signaling with RhoU activation.
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Affiliation(s)
- Jin-San Zhang
- Division of Oncology Research and Schulze Center for Novel Therapeutics
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32
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Fort P, Guémar L, Vignal E, Morin N, Notarnicola C, de Santa Barbara P, Faure S. Activity of the RhoU/Wrch1 GTPase is critical for cranial neural crest cell migration. Dev Biol 2010; 350:451-63. [PMID: 21156169 DOI: 10.1016/j.ydbio.2010.12.011] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2010] [Revised: 11/10/2010] [Accepted: 12/03/2010] [Indexed: 01/09/2023]
Abstract
The neural crest (NC) is a stem cell-like population that arises at the border of neural and non-neural ectoderm. During development, NC undergoes an epithelio-mesenchymal transition (EMT), i.e. loss of epithelial junctions and acquisition of pro-migratory properties, invades the entire embryo and differentiates into a wide diversity of terminal tissues. We have studied the implication of Rho pathways in NC development and previously showed that RhoV is required for cranial neural crest (CNC) cell specification. We show here that the non-canonical Wnt response rhoU/wrch1 gene, closely related to rhoV, is also expressed in CNC cells but at later stages. Using both gain- and loss-of-function experiments, we demonstrate that the level of RhoU expression is critical for CNC cell migration and subsequent differentiation into craniofacial cartilages. In in vitro cultures, RhoU activates pathways that cooperate with PAK1 and Rac1 in epithelial adhesion, cell spreading and directional cell migration. These data support the conclusion that RhoU is an essential regulator of CNC cell migration.
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Affiliation(s)
- Philippe Fort
- Universités Montpellier 2 et 1, CRBM, IFR122, Montpellier, France.
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Regulation of the Rho family small GTPase Wrch-1/RhoU by C-terminal tyrosine phosphorylation requires Src. Mol Cell Biol 2010; 30:4324-38. [PMID: 20547754 DOI: 10.1128/mcb.01646-09] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Wrch-1 is an atypical Rho family small GTPase with roles in migration, epithelial cell morphogenesis, osteoclastogenesis, and oncogenic transformation. Here, we observed rapid relocalization of Wrch-1 from the plasma membrane upon serum stimulation. Studies revealed a requirement for serum-stimulated tyrosine phosphorylation of Wrch-1 at residue Y254 within its C-terminal membrane targeting domain, mediated by the nonreceptor tyrosine kinase Src. Genetic or pharmacological loss of Src kinase activity blocked both phosphorylation and relocalization of Wrch-1. Functionally, Y254 was required for proper Wrch-1 modulation of cystogenesis in three-dimensional culture, and the phospho-deficient mutant, Y254F, was enhanced in Wrch-1-mediated anchorage-independent growth. Mechanistically, C-terminal tyrosine phosphorylation and subsequent relocalization of Wrch-1 downregulated its ability to interact with and activate its effectors by decreasing active Wrch-1-GTP, perhaps by altering proximity to a GEF or GAP. Phospho-deficient Wrch-1(Y254F) remained at the plasma membrane and GTP bound and continued to recruit and activate its effector PAK, even upon serum stimulation. In contrast, a phospho-mimetic mutant, Y254E, was constitutively endosomally localized and GDP bound and failed to recruit PAK unless mutated to be constitutively active/GAP insensitive. C-terminal tyrosine phosphorylation thus represents a new paradigm in posttranslational control of small GTPase localization, activation, and biological function.
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The RhoU/Wrch1 Rho GTPase gene is a common transcriptional target of both the gp130/STAT3 and Wnt-1 pathways. Biochem J 2009; 421:283-92. [PMID: 19397496 DOI: 10.1042/bj20090061] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
STAT3 (signal transducer and activator of transcription 3) is a transcription factor activated by cytokines, growth factors and oncogenes, whose activity is required for cell survival/proliferation of a wide variety of primary tumours and tumour cell lines. Prominent among its multiple effects on tumour cells is the stimulation of cell migration and metastasis, whose functional mechanisms are however not completely characterized. RhoU/Wrch1 (Wnt-responsive Cdc42 homologue) is an atypical Rho GTPase thought to be constitutively bound to GTP. RhoU was first identified as a Wnt-1-inducible mRNA and subsequently shown to act on the actin cytoskeleton by stimulating filopodia formation and stress fibre dissolution. It was in addition recently shown to localize to focal adhesions and to Src-induced podosomes and enhance cell migration. RhoU overexpression in mammary epithelial cells stimulates quiescent cells to re-enter the cell cycle and morphologically phenocopies Wnt-1-dependent transformation. In the present study we show that Wnt-1-mediated RhoU induction occurs at the transcriptional level. Moreover, we demonstrate that RhoU can also be induced by gp130 cytokines via STAT3, and we identify two functional STAT3-binding sites on the mouse RhoU promoter. RhoU induction by Wnt-1 is independent of beta-catenin, but does not involve STAT3. Rather, it is mediated by the Wnt/planar cell polarity pathway through the activation of JNK (c-Jun N-terminal kinase). Both the so-called non-canonical Wnt pathway and STAT3 are therefore able to induce RhoU, which in turn may be involved in mediating their effects on cell migration.
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Brazier H, Pawlak G, Vives V, Blangy A. The Rho GTPase Wrch1 regulates osteoclast precursor adhesion and migration. Int J Biochem Cell Biol 2009; 41:1391-401. [DOI: 10.1016/j.biocel.2008.12.007] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2008] [Revised: 12/08/2008] [Accepted: 12/10/2008] [Indexed: 11/26/2022]
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Stock C, Schwab A. Protons make tumor cells move like clockwork. Pflugers Arch 2009; 458:981-92. [PMID: 19437033 DOI: 10.1007/s00424-009-0677-8] [Citation(s) in RCA: 181] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2009] [Accepted: 04/28/2009] [Indexed: 01/10/2023]
Abstract
Cancer accounts for 13% of the yearly total mortality worldwide. Most cancer deaths are the sequel of metastatic diseases rather than of primary tumor growth. Thus, the major challenge in tumor therapy is the tumor cells' ability to metastasize. The extent to which a tumor metastasizes correlates with the tumor cells' migratory activity. Tumor cell migration requires a coordinated formation and release of cell adhesion contacts, a controlled cytoskeletal dynamics, the digestion and reorganization of the extracellular matrix, and local ion and water transport across the plasma membrane. All of these operations depend on intracellular pH (pH(i)) and extracellular pH (pH(e)). Numerous H(+), HCO (3) (-) , and monocarboxylate transporters as well as different carbonic anhydrase isozymes have considerable impact on pH(i) and pH(e) which spotlights them as possible, potential targets for anticancer therapeutics. Especially in solid tumors whose vascularization is often not sufficient, tumor cells cope with hypoxia and the resulting glycolysis by overexpressing the Na(+)/H(+) exchanger NHE1, monocarboxylate transporters MCT1 and/or MCT4, and the carbonic anhydrase CA IX. NHE1, MCT, and CA IX activity lead to an acidification of the extracellular space in order to maintain the cytosolic pH homeostasis stable. The present article gives a review on how this characteristic, acidic tumor micro- and nanoenvironment controls tumor cell migration.
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Affiliation(s)
- Christian Stock
- Institut für Physiologie II, University of Münster, Robert-Koch-Str. 27b, 48149, Münster, Germany.
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37
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Schlessinger K, Hall A, Tolwinski N. Wnt signaling pathways meet Rho GTPases. Genes Dev 2009; 23:265-77. [PMID: 19204114 DOI: 10.1101/gad.1760809] [Citation(s) in RCA: 290] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Wnt ligands and their receptors orchestrate many essential cellular and physiological processes. During development they control differentiation, proliferation, migration, and patterning, while in the adult, they regulate tissue homeostasis, primarily through their effects on stem cell proliferation and differentiation. Underpinning these diverse biological activities is a complex set of intracellular signaling pathways that are still poorly understood. Rho GTPases have emerged as key mediators of Wnt signals, most notably in the noncanonical pathways that involve polarized cell shape changes and migrations, but also more recently in the canonical pathway leading to beta-catenin-dependent transcription. It appears that Rho GTPases integrate Wnt-induced signals spatially and temporally to promote morphological and transcriptional changes affecting cell behavior.
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Affiliation(s)
- Karni Schlessinger
- Cell Biology, Memorial Sloan-Kettering Cancer Center, New York, New York 10065, USA.
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38
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The transforming Rho family GTPase Wrch-1 disrupts epithelial cell tight junctions and epithelial morphogenesis. Mol Cell Biol 2008; 29:1035-49. [PMID: 19064640 DOI: 10.1128/mcb.00336-08] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Wrch-1, an atypical and transforming Rho GTPase, regulates cellular activities including proliferation and actin organization, but its functions and effectors remain poorly characterized. We show here that Wrch-1 distributes along the apical and basolateral membranes in MDCK cells and binds the cell polarity protein Par6 in a GTP-dependent manner. Activated Wrch-1 negatively regulates the kinetics of tight junction (TJ) assembly during epithelial cell polarization but has no detectable effect on overall cell polarity in confluent monolayers. It also causes a dramatic cytoskeletal reorganization and multilayering in cells grown in two-dimensional culture and disrupts cystogenesis of cells grown in three-dimensional (3D) culture. Similarly, short hairpin RNA-mediated knockdown of Wrch-1 perturbs cystogenesis in 3D culture, suggesting that tight regulation of Wrch-1 activity is necessary for normal epithelial morphogenesis. A weakly transforming effector domain mutant of activated Wrch-1 that inhibits Par6 binding abrogates the ability of Wrch-1 to disrupt TJ formation, actin organization, and epithelial morphogenesis. We hypothesize that Wrch-1-induced morphological and growth transformation may occur in part through Par6-mediated disruption of TJs and actin organization.
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39
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Jonassen JA, San Agustin J, Follit JA, Pazour GJ. Deletion of IFT20 in the mouse kidney causes misorientation of the mitotic spindle and cystic kidney disease. ACTA ACUST UNITED AC 2008; 183:377-84. [PMID: 18981227 PMCID: PMC2575779 DOI: 10.1083/jcb.200808137] [Citation(s) in RCA: 211] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Primary cilia project from the surface of most vertebrate cells and are thought to be sensory organelles. Defects in primary cilia lead to cystic kidney disease, although the ciliary mechanisms that promote and maintain normal renal function remain incompletely understood. In this work, we generated a floxed allele of the ciliary assembly gene Ift20. Deleting this gene specifically in kidney collecting duct cells prevents cilia formation and promotes rapid postnatal cystic expansion of the kidney. Dividing collecting duct cells in early stages of cyst formation fail to properly orient their mitotic spindles along the tubule, whereas nondividing cells improperly position their centrosomes. At later stages, cells lacking cilia have increased canonical Wnt signaling and increased rates of proliferation. Thus, IFT20 functions to couple extracellular events to cell proliferation and differentiation.
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Affiliation(s)
- Julie A Jonassen
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA
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40
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Mruk DD, Silvestrini B, Cheng CY. Anchoring junctions as drug targets: role in contraceptive development. Pharmacol Rev 2008; 60:146-80. [PMID: 18483144 DOI: 10.1124/pr.107.07105] [Citation(s) in RCA: 120] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
In multicellular organisms, cell-cell interactions are mediated in part by cell junctions, which underlie tissue architecture. Throughout spermatogenesis, for instance, preleptotene leptotene spermatocytes residing in the basal compartment of the seminiferous epithelium must traverse the blood-testis barrier to enter the adluminal compartment for continued development. At the same time, germ cells must also remain attached to Sertoli cells, and numerous studies have reported extensive restructuring at the Sertoli-Sertoli and Sertoli-germ cell interface during germ cell movement across the seminiferous epithelium. Furthermore, the proteins and signaling cascades that regulate adhesion between testicular cells have been largely delineated. These findings have unveiled a number of potential "druggable" targets that can be used to induce premature release of germ cells from the seminiferous epithelium, resulting in transient infertility. Herein, we discuss a novel approach with the aim of developing a nonhormonal male contraceptive for future human use, one that involves perturbing adhesion between Sertoli and germ cells in the testis.
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Affiliation(s)
- Dolores D Mruk
- Population Council, Center for Biomedical Research, The Mary M Wohlford Laboratory for Male Contraceptive Research, 1230 York Avenue, New York, NY 10065, USA.
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41
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Ory S, Brazier H, Pawlak G, Blangy A. Rho GTPases in osteoclasts: orchestrators of podosome arrangement. Eur J Cell Biol 2008; 87:469-77. [PMID: 18436334 DOI: 10.1016/j.ejcb.2008.03.002] [Citation(s) in RCA: 105] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2008] [Revised: 03/04/2008] [Accepted: 03/05/2008] [Indexed: 01/05/2023] Open
Abstract
Cells from the myeloid lineage, namely macrophages, dendritic cells and osteoclasts, develop podosomes instead of stress fibers and focal adhesions to adhere and migrate. Podosomes share many components with focal adhesions but differ in their molecular organization, with a dense core of polymerized actin surrounded by scaffolding proteins, kinases and integrins. Podosomes are found either isolated both in macrophages and dendritic cells or arranged into superstructures in osteoclasts. When osteoclasts resorb bone, they form an F-actin rich sealing zone, which is a dense array of connected podosomes that firmly anchors osteoclasts to bone. It delineates a compartment in which protons and proteases are secreted to dissolve and degrade the mineralized matrix. Since Rho GTPases have been shown to control F-actin stress fibers and focal adhesions in mesenchymal cells, the question of whether they could also control podosome formation and arrangement in cells from the myeloid lineage, and particularly in osteoclasts, rapidly emerged. This article considers recent advances made in our understanding of podosome arrangements in osteoclasts and how Rho GTPases may control it.
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Affiliation(s)
- Stéphane Ory
- Centre de Recherche de Biochimie Macromoléculaire, UM2, CNRS, Montpellier, France.
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42
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Guémar L, de Santa Barbara P, Vignal E, Maurel B, Fort P, Faure S. The small GTPase RhoV is an essential regulator of neural crest induction in Xenopus. Dev Biol 2007; 310:113-28. [PMID: 17761159 DOI: 10.1016/j.ydbio.2007.07.031] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2007] [Revised: 07/06/2007] [Accepted: 07/23/2007] [Indexed: 11/26/2022]
Abstract
In vertebrates, the Rho family of GTPases is made of 20 members which regulate a variety of cellular functions, including actin cytoskeleton dynamics, cell adhesion and motility, cell growth and survival, gene transcription and membrane trafficking. To get a comprehensive view of Rho implication in physiological epithelial-mesenchymal transition, we carried out an in situ hybridization-based screen to identify Rho members expressed in Xenopus neural crest cells, in which we previously reported RhoB expression at the migrating stage. In the present study, we identify RhoV as an early expressed neural crest marker and provide evidence that its activity is essential for neural crest cell induction. RhoV mRNA is maternally expressed and accumulates shortly after gastrulation in the neural crest forming region. Using antisense morpholino injection, we show that at neurula stages, RhoV depletion impairs expression of the neural crest markers Sox9, Slug or Twist but has no effect on Snail induction. At the tailbud stage, RhoV knockdown causes a dramatic loss of cranial neural crest derived structures. All these defects are rescued by ectopic wild-type RhoV, whose overexpression on its own expands the neural crest territory. Our findings disclose an unprecedented Rho function in pathways that control neural crest cells specification.
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Affiliation(s)
- Linda Guémar
- Centre de Recherches en Biochimie Macromoléculaire, UMR 5237 CNRS, 1919 route de Mende, 34293 Montpellier, France
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Aspenström P, Ruusala A, Pacholsky D. Taking Rho GTPases to the next level: the cellular functions of atypical Rho GTPases. Exp Cell Res 2007; 313:3673-9. [PMID: 17850788 DOI: 10.1016/j.yexcr.2007.07.022] [Citation(s) in RCA: 126] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2007] [Revised: 07/20/2007] [Accepted: 07/21/2007] [Indexed: 01/18/2023]
Abstract
The Rho GTPases are influential regulators of signalling pathways that control vital cellular processes such as cytoskeletal dynamics, gene transcription, cell cycle progression and cell transformation. A vast majority of the studies involving Rho GTPases have been focused to the famous triad, Cdc42, Rac1 and RhoA, but this protein family actually harbours 20 members. Recently, the less known Rho GTPases have received increased attention. Many of the less studied Rho GTPases have structural, as well as, functional features which makes it pertinent to classify them as atypical Rho GTPases. This review article will focus on the critical aspects of the atypical Rho GTPases, RhoH, Wrch-1, Chp and RhoBTB. These proteins are involved in a broad spectre of biological processes, such as cytoskeletal dynamics, T-cell signalling and protein ubiquitinylation. We will also discuss the roles of atypical Rho GTPases as oncogenes or tumour suppressors, as well as their potential involvement in human diseases.
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Affiliation(s)
- Pontus Aspenström
- Ludwig Institute for Cancer Research, Biomedical Center, Uppsala University, SE-751 24 Uppsala, Sweden.
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