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Read CB, Ali AN, Stephenson DJ, Macknight HP, Maus KD, Cockburn CL, Kim M, Xie X, Carlyon JA, Chalfant CE. Ceramide-1-phosphate is a regulator of Golgi structure and is co-opted by the obligate intracellular bacterial pathogen Anaplasma phagocytophilum. mBio 2024; 15:e0029924. [PMID: 38415594 PMCID: PMC11005342 DOI: 10.1128/mbio.00299-24] [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: 02/05/2024] [Accepted: 02/06/2024] [Indexed: 02/29/2024] Open
Abstract
Many intracellular pathogens structurally disrupt the Golgi apparatus as an evolutionarily conserved promicrobial strategy. Yet, the host factors and signaling processes involved are often poorly understood, particularly for Anaplasma phagocytophilum, the agent of human granulocytic anaplasmosis. We found that A. phagocytophilum elevated cellular levels of the bioactive sphingolipid, ceramide-1-phosphate (C1P), to promote Golgi fragmentation that enables bacterial proliferation, conversion from its non-infectious to infectious form, and productive infection. A. phagocytophilum poorly infected mice deficient in ceramide kinase, the Golgi-localized enzyme responsible for C1P biosynthesis. C1P regulated Golgi morphology via activation of a PKCα/Cdc42/JNK signaling axis that culminates in phosphorylation of Golgi structural proteins, GRASP55 and GRASP65. siRNA-mediated depletion of Cdc42 blocked A. phagocytophilum from altering Golgi morphology, which impaired anterograde trafficking of trans-Golgi vesicles into and maturation of the pathogen-occupied vacuole. Cells overexpressing phosphorylation-resistant versions of GRASP55 and GRASP65 presented with suppressed C1P- and A. phagocytophilum-induced Golgi fragmentation and poorly supported infection by the bacterium. By studying A. phagocytophilum, we identify C1P as a regulator of Golgi structure and a host factor that is relevant to disease progression associated with Golgi fragmentation.IMPORTANCECeramide-1-phosphate (C1P), a bioactive sphingolipid that regulates diverse processes vital to mammalian physiology, is linked to disease states such as cancer, inflammation, and wound healing. By studying the obligate intracellular bacterium Anaplasma phagocytophilum, we discovered that C1P is a major regulator of Golgi morphology. A. phagocytophilum elevated C1P levels to induce signaling events that promote Golgi fragmentation and increase vesicular traffic into the pathogen-occupied vacuole that the bacterium parasitizes. As several intracellular microbial pathogens destabilize the Golgi to drive their infection cycles and changes in Golgi morphology is also linked to cancer and neurodegenerative disorder progression, this study identifies C1P as a potential broad-spectrum therapeutic target for infectious and non-infectious diseases.
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Affiliation(s)
- Curtis B. Read
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, Virginia, USA
| | - Anika N. Ali
- Department of Cell Biology, Microbiology, and Molecular Biology, University of South Florida, Tampa, Florida, USA
| | - Daniel J. Stephenson
- Division of Hematology & Oncology, Department of Medicine, University of Virginia, Charlottesville, Virginia, USA
| | - H. Patrick Macknight
- Division of Hematology & Oncology, Department of Medicine, University of Virginia, Charlottesville, Virginia, USA
| | - Kenneth D. Maus
- Department of Cell Biology, Microbiology, and Molecular Biology, University of South Florida, Tampa, Florida, USA
| | - Chelsea L. Cockburn
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, Virginia, USA
| | - Minjung Kim
- Department of Cell Biology, Microbiology, and Molecular Biology, University of South Florida, Tampa, Florida, USA
| | - Xiujie Xie
- Division of Hematology & Oncology, Department of Medicine, University of Virginia, Charlottesville, Virginia, USA
| | - Jason A. Carlyon
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, Virginia, USA
| | - Charles E. Chalfant
- Division of Hematology & Oncology, Department of Medicine, University of Virginia, Charlottesville, Virginia, USA
- Department of Cell Biology, University of Virginia, Charlottesville, Virginia, USA
- Program in Cancer Biology, University of Virginia Cancer Center, Charlottesville, Virginia, USA
- Research Service, Richmond Veterans Administration Medical Center, Richmond, Virginia, USA
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2
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Dominicci-Cotto C, Vazquez M, Marie B. The Wingless planar cell polarity pathway is essential for optimal activity-dependent synaptic plasticity. Front Synaptic Neurosci 2024; 16:1322771. [PMID: 38633293 PMCID: PMC11021733 DOI: 10.3389/fnsyn.2024.1322771] [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: 10/16/2023] [Accepted: 03/18/2024] [Indexed: 04/19/2024] Open
Abstract
From fly to man, the Wingless (Wg)/Wnt signaling molecule is essential for both the stability and plasticity of the nervous system. The Drosophila neuromuscular junction (NMJ) has proven to be a useful system for deciphering the role of Wg in directing activity-dependent synaptic plasticity (ADSP), which, in the motoneuron, has been shown to be dependent on both the canonical and the noncanonical calcium Wg pathways. Here we show that the noncanonical planar cell polarity (PCP) pathway is an essential component of the Wg signaling system controlling plasticity at the motoneuron synapse. We present evidence that disturbing the PCP pathway leads to a perturbation in ADSP. We first show that a PCP-specific allele of disheveled (dsh) affects the de novo synaptic structures produced during ADSP. We then show that the Rho GTPases downstream of Dsh in the PCP pathway are also involved in regulating the morphological changes that take place after repeated stimulation. Finally, we show that Jun kinase is essential for this phenomenon, whereas we found no indication of the involvement of the transcription factor complex AP1 (Jun/Fos). This work shows the involvement of the neuronal PCP signaling pathway in supporting ADSP. Because we find that AP1 mutants can perform ADSP adequately, we hypothesize that, upon Wg activation, the Rho GTPases and Jun kinase are involved locally at the synapse, in instructing cytoskeletal dynamics responsible for the appearance of the morphological changes occurring during ADSP.
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Affiliation(s)
- Carihann Dominicci-Cotto
- Department of Anatomy and Neurobiology, Medical Sciences Campus, University of Puerto Rico, San Juan, PR, United States
- Institute of Neurobiology, Medical Sciences Campus, University of Puerto Rico, San Juan, PR, United States
| | - Mariam Vazquez
- Institute of Neurobiology, Medical Sciences Campus, University of Puerto Rico, San Juan, PR, United States
- Molecular Sciences Research Center, University of Puerto Rico, San Juan, PR, United States
| | - Bruno Marie
- Department of Anatomy and Neurobiology, Medical Sciences Campus, University of Puerto Rico, San Juan, PR, United States
- Institute of Neurobiology, Medical Sciences Campus, University of Puerto Rico, San Juan, PR, United States
- Molecular Sciences Research Center, University of Puerto Rico, San Juan, PR, United States
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3
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Sakaji K, Ebrahimiazar S, Harigae Y, Ishibashi K, Sato T, Yoshikawa T, Atsumi GI, Sung CH, Saito M. MAST4 promotes primary ciliary resorption through phosphorylation of Tctex-1. Life Sci Alliance 2023; 6:e202301947. [PMID: 37726137 PMCID: PMC10509483 DOI: 10.26508/lsa.202301947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 08/27/2023] [Accepted: 08/28/2023] [Indexed: 09/21/2023] Open
Abstract
The primary cilium undergoes cell cycle-dependent assembly and disassembly. Dysregulated ciliary dynamics are associated with several pathological conditions called ciliopathies. Previous studies showed that the localization of phosphorylated Tctex-1 at Thr94 (T94) at the ciliary base critically regulates ciliary resorption by accelerating actin remodeling and ciliary pocket membrane endocytosis. Here, we show that microtubule-associated serine/threonine kinase family member 4 (MAST4) is localized at the primary cilium. Suppressing MAST4 blocks serum-induced ciliary resorption, and overexpressing MAST4 accelerates ciliary resorption. Tctex-1 binds to the kinase domain of MAST4, in which the R503 and D504 residues are key to MAST4-mediated ciliary resorption. The ciliary resorption and the ciliary base localization of phospho-(T94)Tctex-1 are blocked by the knockdown of MAST4 or the expression of the catalytic-inactive site-directed MAST4 mutants. Moreover, MAST4 is required for Cdc42 activation and Rab5-mediated periciliary membrane endocytosis during ciliary resorption. These results support that MAST4 is a novel kinase that regulates ciliary resorption by modulating the ciliary base localization of phospho-(T94)Tctex-1. MAST4 is a potential new target for treating ciliopathies causally by ciliary resorption defects.
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Affiliation(s)
- Kensuke Sakaji
- Department of Molecular Pharmacology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Sara Ebrahimiazar
- Department of Molecular Pharmacology, Tohoku University Graduate School of Medicine, Sendai, Japan
- Department of Developmental Neuroscience, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Yasuhiro Harigae
- Department of Molecular Pharmacology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Kenichi Ishibashi
- https://ror.org/01gaw2478 Department of Molecular Physiology and Pathology, School of Pharma-Science, Teikyo University, Itabashi-ku, Tokyo, Japan
| | - Takeya Sato
- Department of Molecular Pharmacology, Tohoku University Graduate School of Medicine, Sendai, Japan
- Department of Clinical Biology and Hormonal Regulation, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Takeo Yoshikawa
- Department of Neuropharmacology, Hokkaido University Graduate School of Medicine, Sapporo, Japan
- Department of Pharmacology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Gen-Ichi Atsumi
- https://ror.org/01gaw2478 Department of Molecular Physiology and Pathology, School of Pharma-Science, Teikyo University, Itabashi-ku, Tokyo, Japan
| | - Ching-Hwa Sung
- Department of Ophthalmology, Margaret M. Dyson Vision Research Institute, Weill Cornell Medicine, New York, NY, USA
- Department of Cell and Developmental Biology, Weill Cornell Medicine, New York, NY, USA
| | - Masaki Saito
- Department of Molecular Pharmacology, Tohoku University Graduate School of Medicine, Sendai, Japan
- https://ror.org/01gaw2478 Department of Molecular Physiology and Pathology, School of Pharma-Science, Teikyo University, Itabashi-ku, Tokyo, Japan
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Castillo-Azofeifa D, Wald T, Reyes EA, Gallagher A, Schanin J, Vlachos S, Lamarche-Vane N, Bomidi C, Blutt S, Estes MK, Nystul T, Klein OD. A DLG1-ARHGAP31-CDC42 axis is essential for the intestinal stem cell response to fluctuating niche Wnt signaling. Cell Stem Cell 2023; 30:188-206.e6. [PMID: 36640764 PMCID: PMC9922544 DOI: 10.1016/j.stem.2022.12.008] [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: 03/14/2022] [Revised: 10/13/2022] [Accepted: 12/12/2022] [Indexed: 01/15/2023]
Abstract
A central factor in the maintenance of tissue integrity is the response of stem cells to variations in the levels of niche signals. In the gut, intestinal stem cells (ISCs) depend on Wnt ligands for self-renewal and proliferation. Transient increases in Wnt signaling promote regeneration after injury or in inflammatory bowel diseases, whereas constitutive activation of this pathway leads to colorectal cancer. Here, we report that Discs large 1 (Dlg1), although dispensable for polarity and cellular turnover during intestinal homeostasis, is required for ISC survival in the context of increased Wnt signaling. RNA sequencing (RNA-seq) and genetic mouse models demonstrated that DLG1 regulates the cellular response to increased canonical Wnt ligands. This occurs via the transcriptional regulation of Arhgap31, a GTPase-activating protein that deactivates CDC42, an effector of the non-canonical Wnt pathway. These findings reveal a DLG1-ARHGAP31-CDC42 axis that is essential for the ISC response to increased niche Wnt signaling.
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Affiliation(s)
- David Castillo-Azofeifa
- Department of Orofacial Sciences and Program in Craniofacial Biology, University of California, San Francisco, San Francisco, CA, USA; Department of Regenerative Medicine, Genentech, Inc., South San Francisco, CA, USA
| | - Tomas Wald
- Department of Orofacial Sciences and Program in Craniofacial Biology, University of California, San Francisco, San Francisco, CA, USA
| | - Efren A Reyes
- Department of Orofacial Sciences and Program in Craniofacial Biology, University of California, San Francisco, San Francisco, CA, USA; Department of Pharmaceutical Chemistry and TETRAD Program, University of California, San Francisco, San Francisco, CA, USA
| | - Aaron Gallagher
- Department of Orofacial Sciences and Program in Craniofacial Biology, University of California, San Francisco, San Francisco, CA, USA
| | - Julia Schanin
- Department of Orofacial Sciences and Program in Craniofacial Biology, University of California, San Francisco, San Francisco, CA, USA
| | - Stephanie Vlachos
- Department of Anatomy, University of California, San Francisco, San Francisco, CA, USA
| | - Nathalie Lamarche-Vane
- Cancer Research Program, Research Institute of the McGill University Health Centre, Montréal, QC, Canada; Department of Anatomy and Cell Biology, McGill University, Montréal, QC, Canada
| | - Carolyn Bomidi
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, USA
| | - Sarah Blutt
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, USA
| | - Mary K Estes
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, USA
| | - Todd Nystul
- Department of Anatomy, University of California, San Francisco, San Francisco, CA, USA
| | - Ophir D Klein
- Department of Orofacial Sciences and Program in Craniofacial Biology, University of California, San Francisco, San Francisco, CA, USA; Department of Pediatrics and Institute for Human Genetics, University of California, San Francisco, San Francisco, CA, USA; Department of Pediatrics, Cedars-Sinai Medical Center, Los Angeles, CA, USA.
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5
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Rahman SU, Kim WJ, Chung SH, Woo KM. Nanofibrous topography-driven altered responsiveness to Wnt5a mediates the three-dimensional polarization of odontoblasts. Mater Today Bio 2022; 17:100479. [DOI: 10.1016/j.mtbio.2022.100479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 10/12/2022] [Accepted: 10/27/2022] [Indexed: 11/06/2022]
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6
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Zhou R, Stouffer GA, Frishman WH. Cholesterol Paradigm and Beyond in Atherosclerotic Cardiovascular Disease: Cholesterol, Sterol Regulatory Element-Binding Protein, Inflammation, and Vascular Cell Mobilization in Vasculopathy. Cardiol Rev 2022; 30:267-273. [PMID: 34224448 PMCID: PMC9351696 DOI: 10.1097/crd.0000000000000406] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Hypercholesterolemia is a well-established risk factor for atherosclerotic cardiovascular disease (ASCVD). How cholesterol and its carrier lipoproteins are involved in ASCVD is still under extensive investigation. Satins are thus far the best-proven class of cholesterol-lowering medications to improve the clinical outcomes of ASCVD. Statins specifically inhibit the rate-limiting enzyme 3-hydroxy-3-methylglutaryl-CoA reductase of the mevalonate pathway for cholesterol biosynthesis. The widely accepted theory is that statins inhibit the hepatic cholesterol synthesis causing upregulation of hepatocyte low-density lipoprotein (LDL) receptor; receptor-mediated LDL uptake and metabolism in the liver results in reduction of circulating LDL cholesterol, which subsequently reduces vascular deposition and retention of cholesterol or LDL in atherogenesis. Nevertheless, cholesterol biosynthesis is ubiquitous, also in extrahepatic cells including those in vascular wall, under tight regulation by sterol regulatory element-binding protein (SREBP), the master gene transcription factor governing cholesterol biosynthesis. Studies have shown that SREBP can be upregulated in vascular wall subject to injury or stent implantation. SREBP can be activated by proinflammatory and mitogenic factors in vascular cells, leading to hyperactive mevalonate pathway, which promotes vascular cell mobilization, further proinflammatory and mitogenic factor release from vascular cells, and vascular inflammation. In this article, we review the cellular cholesterol homeostasis regulation by SREBP and SREBP-mediated vascular hyperactive cholesterol biosynthesis, we term vascular hypercholesterolism, in the pathogenesis of ASCVD and vasculopathy. SREBP functions as a platform bridging cholesterol, inflammation, and vascular cell mobilization in ASCVD pathogenesis. Targeting vascular hypercholesterolism could open a new avenue in fighting against ASCVD.
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Affiliation(s)
- Ruihai Zhou
- From the Division of Cardiology, Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC
| | - George A. Stouffer
- From the Division of Cardiology, Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC
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7
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The Process of Filopodia Induction during HPV Infection. Viruses 2022; 14:v14061150. [PMID: 35746622 PMCID: PMC9231133 DOI: 10.3390/v14061150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 05/18/2022] [Accepted: 05/23/2022] [Indexed: 12/04/2022] Open
Abstract
Human Papillomavirus 16 (HPV16) infects mucosal and epithelial cells and has been identified as a high-risk HPV type that is an etiologic agent of human cancers. The initial infectious process, i.e., the binding of the virus particle and its entry into the host cell, has been studied extensively, although it is not fully understood. There is still a gap in understanding the steps by which the virus is able to cross the plasma membrane after receptor binding. In this study, we demonstrate that after HPV16 comes into contact with a plasma membrane receptor, there are cytoskeletal changes resulting in an increase of filopodia numbers. This increase in filopodia numbers was transient and was maintained during the first two hours after virus addition. Our data show that there is a statistically significant increase in infection when filopodia numbers are increased by the addition of drug and virus simultaneously, and a decrease in virus infection when filopodia formation is inhibited. We describe that HPV16 binding results in the activation of Cdc42 GTPase that in turn results in an increase in filopodia. siRNA directed at Cdc42 GTPase resulted in a statistically significant reduction of infection and a corresponding lack of filopodia induction.
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8
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Regulation of local GTP availability controls RAC1 activity and cell invasion. Nat Commun 2021; 12:6091. [PMID: 34667203 PMCID: PMC8526568 DOI: 10.1038/s41467-021-26324-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Accepted: 09/27/2021] [Indexed: 12/04/2022] Open
Abstract
Physiological changes in GTP levels in live cells have never been considered a regulatory step of RAC1 activation because intracellular GTP concentration (determined by chromatography or mass spectrometry) was shown to be substantially higher than the in vitro RAC1 GTP dissociation constant (RAC1-GTP Kd). Here, by combining genetically encoded GTP biosensors and a RAC1 activity biosensor, we demonstrated that GTP levels fluctuating around RAC1-GTP Kd correlated with changes in RAC1 activity in live cells. Furthermore, RAC1 co-localized in protrusions of invading cells with several guanylate metabolism enzymes, including rate-limiting inosine monophosphate dehydrogenase 2 (IMPDH2), which was partially due to direct RAC1-IMPDH2 interaction. Substitution of endogenous IMPDH2 with IMPDH2 mutants incapable of binding RAC1 did not affect total intracellular GTP levels but suppressed RAC1 activity. Targeting IMPDH2 away from the plasma membrane did not alter total intracellular GTP pools but decreased GTP levels in cell protrusions, RAC1 activity, and cell invasion. These data provide a mechanism of regulation of RAC1 activity by local GTP pools in live cells. Changes in intracellular GTP levels are not considered as a regulatory event in RAC1 activation in live cells since total GTP levels are substantially higher than the RAC1 GTP dissociation constant determined in vitro. Here, the authors demonstrate that the availability of free GTP in live cells controls the activity of RAC1 and cell invasion.
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9
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The roles of Cdc42 and Rac1 in the formation of plasma membrane protrusions in cancer epithelial HeLa cells. Mol Biol Rep 2021; 48:4285-4294. [PMID: 34110575 DOI: 10.1007/s11033-021-06443-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Accepted: 05/27/2021] [Indexed: 10/21/2022]
Abstract
The inducible model of clones generated from the cervical cancer epithelial HeLa cell line has shown the role of DOCK10 as a guanine-nucleotide exchange factor for Rho GTPases Cdc42 and Rac1 and as an inducer of filopodia and plasma membrane (PM) ruffles. In this model, constitutively active (CA) mutants of Cdc42 and Rac1 promote filopodia and ruffles, respectively, as in other models. DOCK9 also induces filopodia and ruffles, although ruffling activity is less prominent. By exploiting this model further, the aim of this work is to provide a more complete understanding of the role of Cdc42 and Rac1, and their interactions with DOCK10 and DOCK9, in regulation of PM protrusions. New clones have been generated from HeLa, including single clones expressing one form of wild-type (WT) or dominant negative (DN) Cdc42 or Rac1, and double clones co-expressing one of them together with either DOCK10 or DOCK9. Expression of WT- and DN-Cdc42 induced filopodia. WT-Cdc42 and, especially, DN-Cdc42 also gave rise to veil protrusions, which were neutralized by DOCK10. Moreover, DN-Cdc42 stimulated the emergence of ruffles, further increased by DOCK10, and WT-Cdc42 also augmented ruffles in presence of DOCK9 and DOCK10. WT-Rac1 greatly increased PM blebbing, as did DN-Rac1 more moderately. In both cases, blebs were enhanced by DOCK10. DN-Rac1 and CA-Rac1 moderately raised filopodia, and DOCK10 and DOCK9 had opposed effects on filopodia (up and down, respectively) in presence of WT-Rac1. As conclusions, we highlight that Cdc42 promotes filopodia regardless of its conformational state, and Rac1 induces blebs in conformations other than CA, especially WT-Rac1, in the inducible HeLa clones. The model could be useful to learn more about the mechanisms underlying PM protrusions.
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10
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Liang J, Oyang L, Rao S, Han Y, Luo X, Yi P, Lin J, Xia L, Hu J, Tan S, Tang L, Pan Q, Tang Y, Zhou Y, Liao Q. Rac1, A Potential Target for Tumor Therapy. Front Oncol 2021; 11:674426. [PMID: 34079763 PMCID: PMC8165220 DOI: 10.3389/fonc.2021.674426] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 04/29/2021] [Indexed: 12/20/2022] Open
Abstract
RAS-related C3 botulinum toxin substrate 1 (Rac.1) is one of the important members of Rho GTPases. It is well known that Rac1 is a cytoskeleton regulation protein that regulates cell adhesion, morphology, and movement. Rac1 is highly expressed in different types of tumors, which is related to poor prognosis. Studies have shown that Rac1 not only participates in the tumor cell cycle, apoptosis, proliferation, invasion, migration and angiogenesis, but also participates in the regulation of tumor stem cell, thus promoting the occurrence of tumors. Rac1 also plays a key role in anti-tumor therapy and participates in immune escape mediated by the tumor microenvironment. In addition, the good prospects of Rac1 inhibitors in cancer prevention and treatment are exciting. Therefore, Rac1 is considered as a potential target for the prevention and treatment of cancer. The necessity and importance of Rac1 are obvious, but it still needs further study.
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Affiliation(s)
- Jiaxin Liang
- Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China
| | - Linda Oyang
- Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China
| | - Shan Rao
- Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China
| | - Yaqian Han
- Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China
| | - Xia Luo
- Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China
| | - Pin Yi
- Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China
| | - Jinguan Lin
- Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China
| | - Longzheng Xia
- Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China
| | - Jiaqi Hu
- Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China
| | - Shiming Tan
- Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China
| | - Lu Tang
- Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China.,University of South China, Hengyang, China
| | - Qing Pan
- Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China.,University of South China, Hengyang, China
| | - Yanyan Tang
- Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China.,Clinical Research Center for Wound Healing in Hunan Province, Changsha, China
| | - Yujuan Zhou
- Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China
| | - Qianjin Liao
- Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China.,Clinical Research Center for Wound Healing in Hunan Province, Changsha, China
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11
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Audano M, Pedretti S, Ligorio S, Gualdrini F, Polletti S, Russo M, Ghisletti S, Bean C, Crestani M, Caruso D, De Fabiani E, Mitro N. Zc3h10 regulates adipogenesis by controlling translation and F-actin/mitochondria interaction. J Cell Biol 2021; 220:e202003173. [PMID: 33566069 PMCID: PMC7879490 DOI: 10.1083/jcb.202003173] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 10/29/2020] [Accepted: 12/04/2020] [Indexed: 12/21/2022] Open
Abstract
The commitment of mesenchymal stem cells to preadipocytes is stimulated by hormonal induction. Preadipocytes induced to differentiate repress protein synthesis, remodel their cytoskeleton, and increase mitochondrial function to support anabolic pathways. These changes enable differentiation into mature adipocytes. Our understanding of the factors that coordinately regulate the early events of adipocyte differentiation remains incomplete. Here, by using multipronged approaches, we have identified zinc finger CCCH-type containing 10 (Zc3h10) as a critical regulator of the early stages of adipogenesis. Zc3h10 depletion in preadipocytes resulted in increased protein translation and impaired filamentous (F)-actin remodeling, with the latter detrimental effect leading to mitochondrial and metabolic dysfunction. These defects negatively affected differentiation to mature adipocytes. In contrast, Zc3h10 overexpression yielded mature adipocytes with remarkably increased lipid droplet size. Overall, our study establishes Zc3h10 as a fundamental proadipogenic transcription factor that represses protein synthesis and promotes F-actin/mitochondria dynamics to ensure proper energy metabolism and favor lipid accumulation.
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Affiliation(s)
- Matteo Audano
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milan, Italy
| | - Silvia Pedretti
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milan, Italy
| | - Simona Ligorio
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milan, Italy
| | - Francesco Gualdrini
- Department of Experimental Oncology, European Institute of Oncology, Milan, Italy
- Humanitas University (Hunimed), Pieve Emanuele, Milan, Italy
| | - Sara Polletti
- Department of Experimental Oncology, European Institute of Oncology, Milan, Italy
| | - Marta Russo
- Department of Experimental Oncology, European Institute of Oncology, Milan, Italy
| | - Serena Ghisletti
- Department of Experimental Oncology, European Institute of Oncology, Milan, Italy
| | - Camilla Bean
- Department of Biology, University of Padova, Padua, Italy
- Veneto Institute of Molecular Medicine, Padua, Italy
| | - Maurizio Crestani
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milan, Italy
| | - Donatella Caruso
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milan, Italy
| | - Emma De Fabiani
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milan, Italy
| | - Nico Mitro
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milan, Italy
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12
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Patra T, Bose SK, Kwon YC, Meyer K, Ray R. Inhibition of p70 isoforms of S6K1 induces anoikis to prevent transformed human hepatocyte growth. Life Sci 2021; 265:118764. [PMID: 33189822 DOI: 10.1016/j.lfs.2020.118764] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 11/04/2020] [Accepted: 11/11/2020] [Indexed: 12/21/2022]
Abstract
AIMS The mTOR/S6K1 signaling axis, known for cell growth regulation, is hyper-activated in multiple cancers. In this study, we have examined the mechanisms for ribosomal protein p70-S6 kinase 1 (S6K1) associated transformed human hepatocyte (THH) growth regulation. MAIN METHODS THH were treated with p70-S6K1 inhibitor and analyzed for cell viability, cell cycle distribution, specific marker protein expression by western blot, and tumor inhibition in a xenograft mouse model. We validated our results by knockdown of p70-S6K1 using specific siRNA. KEY FINDINGS p70-S6K1 inhibitor treatment caused impairment of in vitro hepatocyte growth, and arrested cell cycle progression at the G1 phase. Further, p70-S6K1 inhibitor treatment exhibited a decrease in FAK and Erk activation, followed by altered integrin-β1 expression, caspase 8, and PARP cleavage appeared to be anoikis like growth inhibition. p70-S6K1 inhibitor also depolymerized actin microfilaments and diminished active Rac1/Cdc42 complex formation for loss of cellular attachment. Similar results were obtained with other transformed human hepatocyte cell lines. p70-S6K1 inhibition also resulted in a reduced phospho-EGFR, Slug and Twist; implicating an inhibition of epithelial-mesenchymal transition (EMT) state. A xenograft tumor model, generated from implanted THH in nude mice, following intraperitoneal injection of S6K1 inhibitor prevented further tumor growth. SIGNIFICANCE Our results suggested that p70-S6K1 inhibition alters orchestration of cell cycle progression, induces cell detachment, and sensitizes hepatocyte growth impairment. Targeting p70 isoform of S6K1 by inhibitor may prove to be a promising approach together with other therapies for hepatocellular carcinoma (HCC) treatment.
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Affiliation(s)
- Tapas Patra
- Departments of Internal Medicine, Saint Louis University, MO, USA.
| | - Sandip K Bose
- Departments of Internal Medicine, Saint Louis University, MO, USA; Molecular Microbiology & Immunology, Saint Louis University, MO, USA
| | - Young-Chan Kwon
- Departments of Internal Medicine, Saint Louis University, MO, USA
| | - Keith Meyer
- Departments of Internal Medicine, Saint Louis University, MO, USA
| | - Ranjit Ray
- Departments of Internal Medicine, Saint Louis University, MO, USA; Molecular Microbiology & Immunology, Saint Louis University, MO, USA.
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13
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Pal D, Ellis A, Sepúlveda-Ramírez SP, Salgado T, Terrazas I, Reyes G, De La Rosa R, Henson JH, Shuster CB. Rac and Arp2/3-Nucleated Actin Networks Antagonize Rho During Mitotic and Meiotic Cleavages. Front Cell Dev Biol 2020; 8:591141. [PMID: 33282870 PMCID: PMC7705106 DOI: 10.3389/fcell.2020.591141] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 10/20/2020] [Indexed: 12/01/2022] Open
Abstract
In motile cells, the activities of the different Rho family GTPases are spatially segregated within the cell, and during cytokinesis there is evidence that this may also be the case. But while Rho’s role as the central organizer for contractile ring assembly is well established, the role of Rac and the branched actin networks it promotes is less well understood. To characterize the contributions of these proteins during cytokinesis, we manipulated Rac and Arp2/3 activity during mitosis and meiosis in sea urchin embryos and sea star oocytes. While neither Rac nor Arp2/3 were essential for early embryonic divisions, loss of either Rac or Arp2/3 activity resulted in polar body defects. Expression of activated Rac resulted in cytokinesis failure as early as the first division, and in oocytes, activated Rac suppressed both the Rho wave that traverses the oocyte prior to polar body extrusion as well as polar body formation itself. However, the inhibitory effect of Rac on cytokinesis, polar body formation and the Rho wave could be suppressed by effector-binding mutations or direct inhibition of Arp2/3. Together, these results suggest that Rac- and Arp2/3 mediated actin networks may directly antagonize Rho signaling, thus providing a potential mechanism to explain why Arp2/3-nucleated branched actin networks must be suppressed at the cell equator for successful cytokinesis.
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Affiliation(s)
- Debadrita Pal
- Department of Biology, New Mexico State University, Las Cruces, NM, United States
| | - Andrea Ellis
- Department of Biology, New Mexico State University, Las Cruces, NM, United States
| | | | - Torey Salgado
- Department of Biology, New Mexico State University, Las Cruces, NM, United States
| | - Isabella Terrazas
- Department of Biology, New Mexico State University, Las Cruces, NM, United States
| | - Gabriela Reyes
- Department of Biology, New Mexico State University, Las Cruces, NM, United States
| | - Richard De La Rosa
- Department of Biology, New Mexico State University, Las Cruces, NM, United States
| | - John H Henson
- Department of Biology, Dickinson College, Carlisle, PA, United States
| | - Charles B Shuster
- Department of Biology, New Mexico State University, Las Cruces, NM, United States
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14
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Vav2 catalysis-dependent pathways contribute to skeletal muscle growth and metabolic homeostasis. Nat Commun 2020; 11:5808. [PMID: 33199701 PMCID: PMC7669868 DOI: 10.1038/s41467-020-19489-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 10/16/2020] [Indexed: 12/17/2022] Open
Abstract
Skeletal muscle promotes metabolic balance by regulating glucose uptake and the stimulation of multiple interorgan crosstalk. We show here that the catalytic activity of Vav2, a Rho GTPase activator, modulates the signaling output of the IGF1- and insulin-stimulated phosphatidylinositol 3-kinase pathway in that tissue. Consistent with this, mice bearing a Vav2 protein with decreased catalytic activity exhibit reduced muscle mass, lack of proper insulin responsiveness and, at much later times, a metabolic syndrome-like condition. Conversely, mice expressing a catalytically hyperactive Vav2 develop muscle hypertrophy and increased insulin responsiveness. Of note, while hypoactive Vav2 predisposes to, hyperactive Vav2 protects against high fat diet-induced metabolic imbalance. These data unveil a regulatory layer affecting the signaling output of insulin family factors in muscle. Skeletal muscle plays a key role in regulating systemic glucose and metabolic homeostasis. Here, the authors show that the catalytic activity of Vav2, an activator of Rho GTPases, modulates those processes by favoring the responsiveness of this tissue to insulin and related factors.
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15
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Colón-Bolea P, García-Gómez R, Shackleton S, Crespo P, Bustelo XR, Casar B. RAC1 induces nuclear alterations through the LINC complex to enhance melanoma invasiveness. Mol Biol Cell 2020; 31:2768-2778. [PMID: 33026942 PMCID: PMC7851868 DOI: 10.1091/mbc.e20-02-0127] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
RHO GTPases are key regulators of the cytoskeletal architecture, which impact a broad range of biological processes in malignant cells including motility, invasion, and metastasis, thereby affecting tumor progression. One of the constraints during cell migration is the diameter of the pores through which cells pass. In this respect, the size and shape of the nucleus pose a major limitation. Therefore, enhanced nuclear plasticity can promote cell migration. Nuclear morphology is determined in part through the cytoskeleton, which connects to the nucleoskeleton through the Linker of Nucleoskeleton and Cytoskeleton (LINC) complex. Here, we unravel the role of RAC1 as an orchestrator of nuclear morphology in melanoma cells. We demonstrate that activated RAC1 promotes nuclear alterations through its effector PAK1 and the tubulin cytoskeleton, thereby enhancing migration and intravasation of melanoma cells. Disruption of the LINC complex prevented RAC1-induced nuclear alterations and the invasive properties of melanoma cells. Thus, RAC1 induces nuclear morphology alterations through microtubules and the LINC complex to promote an invasive phenotype in melanoma cells.
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Affiliation(s)
- Paula Colón-Bolea
- Instituto de Biomedicina y Biotecnología de Cantabria, Consejo Superior de Investigaciones Científicas (CSIC), Universidad de Cantabria, Santander 39011, Spain
| | - Rocío García-Gómez
- Instituto de Biomedicina y Biotecnología de Cantabria, Consejo Superior de Investigaciones Científicas (CSIC), Universidad de Cantabria, Santander 39011, Spain.,Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), Instituto de Salud Carlos III, Madrid 28029, Spain
| | - Sue Shackleton
- Department of Biochemistry, University of Leicester, Leicester LE1 9HM, UK
| | - Piero Crespo
- Instituto de Biomedicina y Biotecnología de Cantabria, Consejo Superior de Investigaciones Científicas (CSIC), Universidad de Cantabria, Santander 39011, Spain.,Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), Instituto de Salud Carlos III, Madrid 28029, Spain
| | - Xosé R Bustelo
- Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), Instituto de Salud Carlos III, Madrid 28029, Spain.,Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer (CSIC), Universidad de Salamanca, Salamanca 37007, Spain
| | - Berta Casar
- Instituto de Biomedicina y Biotecnología de Cantabria, Consejo Superior de Investigaciones Científicas (CSIC), Universidad de Cantabria, Santander 39011, Spain.,Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), Instituto de Salud Carlos III, Madrid 28029, Spain
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16
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Hodge RG, Schaefer A, Howard SV, Der CJ. RAS and RHO family GTPase mutations in cancer: twin sons of different mothers? Crit Rev Biochem Mol Biol 2020; 55:386-407. [PMID: 32838579 DOI: 10.1080/10409238.2020.1810622] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The RAS and RHO family comprise two major branches of the RAS superfamily of small GTPases. These proteins function as regulated molecular switches and control cytoplasmic signaling networks that regulate a diversity of cellular processes, including cell proliferation and cell migration. In the early 1980s, mutationally activated RAS genes encoding KRAS, HRAS and NRAS were discovered in human cancer and now comprise the most frequently mutated oncogene family in cancer. Only recently, exome sequencing studies identified cancer-associated alterations in two RHO family GTPases, RAC1 and RHOA. RAS and RHO proteins share significant identity in their amino acid sequences, protein structure and biochemistry. Cancer-associated RAS mutant proteins harbor missense mutations that are found primarily at one of three mutational hotspots (G12, G13 and Q61) and have been identified as gain-of-function oncogenic alterations. Although these residues are conserved in RHO family proteins, the gain-of-function mutations found in RAC1 are found primarily at a distinct hotspot. Unexpectedly, the cancer-associated mutations found with RHOA are located at different hotspots than those found with RAS. Furthermore, since the RHOA mutations suggested a loss-of-function phenotype, it has been unclear whether RHOA functions as an oncogene or tumor suppressor in cancer development. Finally, whereas RAS mutations are found in a broad spectrum of cancer types, RHOA and RAC1 mutations occur in a highly restricted range of cancer types. In this review, we focus on RHOA missense mutations found in cancer and their role in driving tumorigenesis, with comparisons to cancer-associated mutations in RAC1 and RAS GTPases.
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Affiliation(s)
- Richard G Hodge
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Antje Schaefer
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.,Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Sarah V Howard
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Channing J Der
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.,Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
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17
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Yu Q, Zhang B, Zhang YM, Liu YH, Liu Y. Actin Cytoskeleton-Disrupting and Magnetic Field-Responsive Multivalent Supramolecular Assemblies for Efficient Cancer Therapy. ACS APPLIED MATERIALS & INTERFACES 2020; 12:13709-13717. [PMID: 32118400 DOI: 10.1021/acsami.0c01762] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Actin cytoskeleton disruption is a promising and intriguing anticancer strategy, but their efficiency is frequently compromised by severe side effects of the actin cytoskeleton-disrupting agents. In this study, we constructed the biocompatible actin cytoskeleton-targeting multivalent supramolecular assemblies that specifically target and disrupt the tumor actin cytoskeleton for cancer therapy. The assemblies were composed of β-cyclodextrin-grafted hyaluronic acid (HACD) and iron oxide magnetic nanoparticles (MNPs) grafted by an actin-binding peptide (ABP) and adamantane (Ada)-modified polylysine. Owing to the multivalent binding between cyclodextrin and Ada, HACD, and peptide-grafted MNPs (MNP-ABP-Ada) could self-assemble to form MNP-ABP-Ada⊂HACD nanofibers in a geomagnetism-dependent manner. Furthermore, the presence of ABP rendered the assemblies to efficiently target the actin cytoskeleton. Interestingly, with the acid of a low-frequency alternating magnetic field (200 Hz), the actin cytoskeleton-targeting nanofibers could induce severe actin disruption, leading to a remarkable cell cycle arrest and drastic cell death of tumor cells both in vitro and in vivo, but showed no obvious toxicity to normal cells. The actin cytoskeleton-targeting/disrupting supramolecular assembly implies an excellent strategy for realizing efficient cancer therapy.
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Affiliation(s)
- Qilin Yu
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Department of Microbiology, College of Life Science, Nankai University, Tianjin 300071, P. R. China
- College of Chemistry, State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, P. R. China
| | - Bing Zhang
- College of Chemistry, State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, P. R. China
| | - Ying-Ming Zhang
- College of Chemistry, State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, P. R. China
| | - Yao-Hua Liu
- College of Chemistry, State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, P. R. China
| | - Yu Liu
- College of Chemistry, State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, P. R. China
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18
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Qi S, Perrino S, Miao X, Lamarche-Vane N, Brodt P. The chemokine CCL7 regulates invadopodia maturation and MMP-9 mediated collagen degradation in liver-metastatic carcinoma cells. Cancer Lett 2020; 483:98-113. [PMID: 32217106 DOI: 10.1016/j.canlet.2020.03.018] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 03/01/2020] [Accepted: 03/17/2020] [Indexed: 01/01/2023]
Abstract
Liver metastases remain a major cause of death from gastrointestinal tract cancers and other malignancies, such as breast and lung carcinomas. Understanding the underlying biology is essential for the design of effective therapies. We previously identified the chemokine CCL7 and its receptor CCR3 as critical mediators of invasion and metastasis in lung and colon carcinoma cells. Here we show that the CCL7/CCR3 axis regulates a late stage in invadopodia genesis namely, the targeting of MMP-9 to the invadopodia complex, thereby promoting invadopodia maturation and collagen degradation. We show that this process could be blocked by overexpression of a dominant negative RhoA in highly invasive cells, while a constitutively active RhoA upregulated invadopodia maturation in CCL7-silenced and poorly invasive and metastatic cells and also enhanced their metastatic potential in vivo, collectively, implicating RhoA activation in signaling downstream of CCL7. Blockade of the ERK or PI3K pathways by chemical inhibitors also inhibited invadopodia formation, but affected the initiation stage of invadopodia genesis. Our data implicate CCL7/CCR3 signaling in invadopodia maturation and suggest that chemokine signaling acts in concert with extracellular matrix-initiated signals to promote invasion and liver metastasis.
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Affiliation(s)
- Shu Qi
- Department of Surgery, Research Institute of the McGill University Health Centre, 1001 Décarie Blvd, Glen Site, Room E.02.6230, Montréal, QC, H4A 3J1, Canada; Department of the Cancer Research Program, Research Institute of the McGill University Health Centre 1001 Décarie Blvd, Glen Site, Room E.02.6230, Montréal, QC, H4A 3J1, Canada.
| | - Stephanie Perrino
- Department of Surgery, Research Institute of the McGill University Health Centre, 1001 Décarie Blvd, Glen Site, Room E.02.6230, Montréal, QC, H4A 3J1, Canada; Department of the Cancer Research Program, Research Institute of the McGill University Health Centre 1001 Décarie Blvd, Glen Site, Room E.02.6230, Montréal, QC, H4A 3J1, Canada.
| | - Xinyu Miao
- Departments of Anatomy and Cell Biology, Research Institute of the McGill University Health Centre 1001 Décarie Blvd, Glen Site, Room E.02.6230, Montréal, QC, H4A 3J1, Canada; Department of McGill University, Research Institute of the McGill University Health Centre 1001 Décarie Blvd, Glen Site, Room E.02.6230, Montréal, QC, H4A 3J1, Canada; Department of the Cancer Research Program, Research Institute of the McGill University Health Centre 1001 Décarie Blvd, Glen Site, Room E.02.6230, Montréal, QC, H4A 3J1, Canada.
| | - Nathalie Lamarche-Vane
- Departments of Anatomy and Cell Biology, Research Institute of the McGill University Health Centre 1001 Décarie Blvd, Glen Site, Room E.02.6230, Montréal, QC, H4A 3J1, Canada; Department of McGill University, Research Institute of the McGill University Health Centre 1001 Décarie Blvd, Glen Site, Room E.02.6230, Montréal, QC, H4A 3J1, Canada; Department of the Cancer Research Program, Research Institute of the McGill University Health Centre 1001 Décarie Blvd, Glen Site, Room E.02.6230, Montréal, QC, H4A 3J1, Canada.
| | - Pnina Brodt
- Department of Surgery, Research Institute of the McGill University Health Centre, 1001 Décarie Blvd, Glen Site, Room E.02.6230, Montréal, QC, H4A 3J1, Canada; Department of Medicine, Research Institute of the McGill University Health Centre, 1001 Décarie Blvd, Glen Site, Room E.02.6230, Montréal, QC, H4A 3J1, Canada; Department of Oncology, Research Institute of the McGill University Health Centre 1001 Décarie Blvd, Glen Site, Room E.02.6230, Montréal, QC, H4A 3J1, Canada; Department of McGill University, Research Institute of the McGill University Health Centre 1001 Décarie Blvd, Glen Site, Room E.02.6230, Montréal, QC, H4A 3J1, Canada; Department of the Cancer Research Program, Research Institute of the McGill University Health Centre 1001 Décarie Blvd, Glen Site, Room E.02.6230, Montréal, QC, H4A 3J1, Canada.
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19
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Identification of Important Proteins and Pathways Affecting Feed Efficiency in DLY Pigs by iTRAQ-Based Proteomic Analysis. Animals (Basel) 2020; 10:ani10020189. [PMID: 31978958 PMCID: PMC7070517 DOI: 10.3390/ani10020189] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Revised: 01/18/2020] [Accepted: 01/20/2020] [Indexed: 01/10/2023] Open
Abstract
Simple Summary Feed efficiency is one of the most valuable economic traits in the pig industry. The small intestine is the site where most of the nutrients are absorbed from ingested food. Here, we studied the relationship between small intestinal proteomics and feed efficiency in Duroc × (Landrace × Yorkshire) pigs, which is the most popular commercial pig in the Chinese pork market. Exploring the molecular mechanisms of feed efficiency will create great value for the pig industry. Our research provided a reference for further understanding of the key proteins that affect small intestinal microvilli formation and the important pathways related to feed efficiency in pigs. Abstract Feed efficiency is an economically important trait controlled by multiple genes in pigs. The small intestine is the main organ of digestion and nutrient absorption. To explore the biological processes by which small intestine proteomics affects feed efficiency (FE), we investigated the small intestinal tissue proteomes of high-FE and low-FE pigs by the isobaric tag for relative and absolute quantification (iTRAQ) method. In this study, a total of 225 Duroc × (Landrace × Yorkshire) (DLY) commercial pigs were ranked according to feed efficiency, which ranged from 30 kg to 100 kg, and six pigs with extreme phenotypes were selected, three in each of the high and low groups. A total of 1219 differentially expressed proteins (DEPs) were identified between the high-FE and low-FE groups (fold change ≥1.2 or ≤0.84; p ≤ 0.05), of which 785 were upregulated, and 484 were downregulated. Enrichment analysis indicated that the DEPs were mainly enriched in actin filament formation, microvilli formation, and small intestinal movement pathways. Protein functional analysis and protein interaction networks indicated that RHOA, HCLS1, EZR, CDC42, and RAC1 were important proteins that regulate FE in pigs. This study provided new insights into the important pathways and proteins involved in feed efficiency in pigs.
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20
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Huck K, Sens C, Wuerfel C, Zoeller C, A. Nakchbandi I. The Rho GTPase RAC1 in Osteoblasts Controls Their Function. Int J Mol Sci 2020; 21:ijms21020385. [PMID: 31936261 PMCID: PMC7014472 DOI: 10.3390/ijms21020385] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 12/23/2019] [Accepted: 12/31/2019] [Indexed: 12/25/2022] Open
Abstract
The regulation of the differentiation of the bone-forming cells, the osteoblasts, is complex. Many signaling pathways converge on the master regulator of osteoblast differentiation Runx2. The role of molecules that integrate several signaling pathways such as the Rho GTPases need to be better understood. We, therefore, asked at which stage Rac1, one of the Rho GTPase, is needed for osteoblast differentiation and whether it is involved in two pathways, the anabolic response to parathyroid hormone and the stimulatory effect of fibronectin isoforms on integrins. Genetic deletion of Rac1 in preosteoblasts using the osterix promoter diminished osteoblast differentiation in vitro. This effect was however similar to the presence of the promoter by itself. We, therefore, applied a Rac1 inhibitor and confirmed a decrease in differentiation. In vivo, Rac1 deletion using the osterix promoter decreased bone mineral density as well as histomorphometric measures of osteoblast function. In contrast, deleting Rac1 in differentiating osteoblasts using the collagen α1(I) promoter had no effects. We then evaluated whether intermittent parathyroid hormone (PTH) was able to affect bone mineral density in the absence of Rac1 in preosteoblasts. The increase in bone mineral density was similar in control animals and in mice in which Rac1 was deleted using the osterix promoter. Furthermore, stimulation of integrin by integrin isoforms was able to enhance osteoblast differentiation, despite the deletion of Rac1. In summary, Rac1 in preosteoblasts is required for normal osteoblast function and bone density, but it is neither needed for PTH-mediated anabolic effects nor for integrin-mediated enhancement of differentiation.
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Affiliation(s)
- Katrin Huck
- Institute of Immunology, University of Heidelberg, 69120 Heidelberg, Germany; (K.H.); (C.S.); (C.W.); (C.Z.)
- Max-Planck Institute for Medical Research, 69120 Heidelberg, and for Biochemistry, 82152 Martinsried, Germany
| | - Carla Sens
- Institute of Immunology, University of Heidelberg, 69120 Heidelberg, Germany; (K.H.); (C.S.); (C.W.); (C.Z.)
- Max-Planck Institute for Medical Research, 69120 Heidelberg, and for Biochemistry, 82152 Martinsried, Germany
| | - Carina Wuerfel
- Institute of Immunology, University of Heidelberg, 69120 Heidelberg, Germany; (K.H.); (C.S.); (C.W.); (C.Z.)
- Max-Planck Institute for Medical Research, 69120 Heidelberg, and for Biochemistry, 82152 Martinsried, Germany
| | - Caren Zoeller
- Institute of Immunology, University of Heidelberg, 69120 Heidelberg, Germany; (K.H.); (C.S.); (C.W.); (C.Z.)
- Max-Planck Institute for Medical Research, 69120 Heidelberg, and for Biochemistry, 82152 Martinsried, Germany
| | - Inaam A. Nakchbandi
- Institute of Immunology, University of Heidelberg, 69120 Heidelberg, Germany; (K.H.); (C.S.); (C.W.); (C.Z.)
- Max-Planck Institute for Medical Research, 69120 Heidelberg, and for Biochemistry, 82152 Martinsried, Germany
- Correspondence: ; Tel.: +49-6221-56-8744; Fax: +49-6221-56-5611
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21
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Mohan AS, Dean KM, Isogai T, Kasitinon SY, Murali VS, Roudot P, Groisman A, Reed DK, Welf ES, Han SJ, Noh J, Danuser G. Enhanced Dendritic Actin Network Formation in Extended Lamellipodia Drives Proliferation in Growth-Challenged Rac1 P29S Melanoma Cells. Dev Cell 2020; 49:444-460.e9. [PMID: 31063759 DOI: 10.1016/j.devcel.2019.04.007] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 01/21/2019] [Accepted: 04/05/2019] [Indexed: 12/19/2022]
Abstract
Actin assembly supplies the structural framework for cell morphology and migration. Beyond structure, this actin framework can also be engaged to drive biochemical signaling programs. Here, we describe how the hyperactivation of Rac1 via the P29S mutation (Rac1P29S) in melanoma hijacks branched actin network assembly to coordinate proliferative cues that facilitate metastasis and drug resistance. Upon growth challenge, Rac1P29S-harboring melanoma cells massively upregulate lamellipodia formation by dendritic actin polymerization. These extended lamellipodia form a signaling microdomain that sequesters and phospho-inactivates the tumor suppressor NF2/Merlin, driving Rac1P29S cell proliferation in growth suppressive conditions. These biochemically active lamellipodia require cell-substrate attachment but not focal adhesion assembly and drive proliferation independently of the ERK/MAPK pathway. These data suggest a critical link between cell morphology and cell signaling and reconcile the dichotomy of Rac1's regulation of both proliferation and actin assembly by revealing a mutual signaling axis wherein actin assembly drives proliferation in melanoma.
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Affiliation(s)
- Ashwathi S Mohan
- Lyda Hill Department of Bioinformatics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Kevin M Dean
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Tadamoto Isogai
- Lyda Hill Department of Bioinformatics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Stacy Y Kasitinon
- Children's Research Institute and the Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Vasanth S Murali
- Lyda Hill Department of Bioinformatics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Philippe Roudot
- Lyda Hill Department of Bioinformatics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Alex Groisman
- Department of Physics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Dana K Reed
- Lyda Hill Department of Bioinformatics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Erik S Welf
- Lyda Hill Department of Bioinformatics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Sangyoon J Han
- Lyda Hill Department of Bioinformatics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Biomedical Engineering, Michigan Technological University, Houghton, MI 49931, USA
| | - Jungsik Noh
- Lyda Hill Department of Bioinformatics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Gaudenz Danuser
- Lyda Hill Department of Bioinformatics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
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22
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Naci D, Berrazouane S, Barabé F, Aoudjit F. Cell adhesion to collagen promotes leukemia resistance to doxorubicin by reducing DNA damage through the inhibition of Rac1 activation. Sci Rep 2019; 9:19455. [PMID: 31857649 PMCID: PMC6923425 DOI: 10.1038/s41598-019-55934-w] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Accepted: 12/04/2019] [Indexed: 01/13/2023] Open
Abstract
Chemoresistance is a major hurdle in anti-cancer therapy. Growing evidence indicates that integrin-mediated cell adhesion to extracellular matrix plays a major role in chemoresistance. However, the underlying mechanisms are not fully understood. We have previously shown that the collagen-binding integrin α2β1 promoted doxorubicin resistance in acute T cell lymphoblastic leukemia (T-ALL). In this study, we found that acute myeloid leukemia (AML) cell lines also express α2β1 integrin and collagen promoted their chemoresistance as well. Furthermore, we found that high levels of α2 integrin correlate with worse overall survival in AML. Our results showed that doxorubicin-induced apoptosis in leukemic cells is associated with activation of Ras-related C3 botulinum toxin substrate 1 (Rac1) and that collagen inhibited this pathway. The protective effect of collagen is associated with the inhibition of Rac1-induced DNA damage as evaluated by the comet assay and the phosphorylated levels of histone H2AX (γ-H2AX). Together these results show that by inhibiting pro-apoptotic Rac1, α2β1 integrin can be a major pathway protecting leukemic cells from genotoxic agents and may thus represent an important therapeutic target in anti-cancer treatment.
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Affiliation(s)
- Dalila Naci
- Centre de recherche du CHU de Québec-Université Laval, Axe des maladies infectieuses et immunitaires, Québec, Canada.,The Hospital for Sick Children, University of Toronto, Toronto, Canada
| | - Sofiane Berrazouane
- Centre de recherche du CHU de Québec-Université Laval, Axe des maladies infectieuses et immunitaires, Québec, Canada
| | - Frédéric Barabé
- Centre de recherche du CHU de Québec-Université Laval, Axe des maladies infectieuses et immunitaires, Québec, Canada.,Département de Médicine, Faculté de Médecine, Université Laval, Québec, Canada
| | - Fawzi Aoudjit
- Centre de recherche du CHU de Québec-Université Laval, Axe des maladies infectieuses et immunitaires, Québec, Canada. .,Département de Microbiologie-infectiologie et Immunologie, Faculté de Médecine, Université Laval, Québec, Canada.
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23
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Brezovjakova H, Tomlinson C, Mohd Naim N, Swiatlowska P, Erasmus JC, Huveneers S, Gorelik J, Bruche S, Braga VM. Junction Mapper is a novel computer vision tool to decipher cell-cell contact phenotypes. eLife 2019; 8:45413. [PMID: 31793877 PMCID: PMC7034980 DOI: 10.7554/elife.45413] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 12/02/2019] [Indexed: 12/19/2022] Open
Abstract
Stable cell–cell contacts underpin tissue architecture and organization. Quantification of junctions of mammalian epithelia requires laborious manual measurements that are a major roadblock for mechanistic studies. We designed Junction Mapper as an open access, semi-automated software that defines the status of adhesiveness via the simultaneous measurement of pre-defined parameters at cell–cell contacts. It identifies contacting interfaces and corners with minimal user input and quantifies length, area and intensity of junction markers. Its ability to measure fragmented junctions is unique. Importantly, junctions that considerably deviate from the contiguous staining and straight contact phenotype seen in epithelia are also successfully quantified (i.e. cardiomyocytes or endothelia). Distinct phenotypes of junction disruption can be clearly differentiated among various oncogenes, depletion of actin regulators or stimulation with other agents. Junction Mapper is thus a powerful, unbiased and highly applicable software for profiling cell–cell adhesion phenotypes and facilitate studies on junction dynamics in health and disease.
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Affiliation(s)
- Helena Brezovjakova
- National Heart and Lung Institute, National Institutes of Health, London, United Kingdom
| | - Chris Tomlinson
- Bioinformatics Data Science Group, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Noor Mohd Naim
- National Heart and Lung Institute, National Institutes of Health, London, United Kingdom
| | - Pamela Swiatlowska
- National Heart and Lung Institute, National Institutes of Health, London, United Kingdom
| | - Jennifer C Erasmus
- National Heart and Lung Institute, National Institutes of Health, London, United Kingdom
| | - Stephan Huveneers
- Department Medical Biochemistry, Amsterdam Cardiovascular Sciences, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Julia Gorelik
- National Heart and Lung Institute, National Institutes of Health, London, United Kingdom
| | - Susann Bruche
- National Heart and Lung Institute, National Institutes of Health, London, United Kingdom
| | - Vania Mm Braga
- National Heart and Lung Institute, National Institutes of Health, London, United Kingdom
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24
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Huang C, Chen Q, Xu X, Wu X. miR-195 inhibits esophageal cancer cell proliferation via targeting cyclin D1 and Cdc42. Pharmacotherapy 2019. [DOI: 10.1016/j.biopha.2019.109525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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25
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Sasaki Y, Oshikawa M, Bharmoria P, Kouno H, Hayashi‐Takagi A, Sato M, Ajioka I, Yanai N, Kimizuka N. Near‐Infrared Optogenetic Genome Engineering Based on Photon‐Upconversion Hydrogels. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201911025] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Yoichi Sasaki
- Department of Chemistry and Biochemistry Graduate School of Engineering Center for Molecular Systems (CMS) Kyushu University 744 Moto-oka, Nishi-ku Fukuoka 819-0395 Japan
| | - Mio Oshikawa
- Center for Brain Integration Research (CBIR) Tokyo Medical and Dental University (TMDU) 1-5-45 Yushima, Bunkyo-ku Tokyo 113–8510 Japan
| | - Pankaj Bharmoria
- Department of Chemistry and Biochemistry Graduate School of Engineering Center for Molecular Systems (CMS) Kyushu University 744 Moto-oka, Nishi-ku Fukuoka 819-0395 Japan
| | - Hironori Kouno
- Department of Chemistry and Biochemistry Graduate School of Engineering Center for Molecular Systems (CMS) Kyushu University 744 Moto-oka, Nishi-ku Fukuoka 819-0395 Japan
| | - Akiko Hayashi‐Takagi
- Laboratory of Medical Neuroscience Institute for Molecular and Cellular Regulation Gunma University Maebashi-city Gunma 371-8512 Japan
- PRESTO JST Honcho 4-1-8 Kawaguchi Saitama 332-0012 Japan
| | - Moritoshi Sato
- Graduate School of Arts and Sciences The University of Tokyo, Komaba, Meguro-ku Tokyo 153-8902 Japan
| | - Itsuki Ajioka
- Center for Brain Integration Research (CBIR) Tokyo Medical and Dental University (TMDU) 1-5-45 Yushima, Bunkyo-ku Tokyo 113–8510 Japan
- PRESTO JST Honcho 4-1-8 Kawaguchi Saitama 332-0012 Japan
| | - Nobuhiro Yanai
- Department of Chemistry and Biochemistry Graduate School of Engineering Center for Molecular Systems (CMS) Kyushu University 744 Moto-oka, Nishi-ku Fukuoka 819-0395 Japan
- PRESTO JST Honcho 4-1-8 Kawaguchi Saitama 332-0012 Japan
| | - Nobuo Kimizuka
- Department of Chemistry and Biochemistry Graduate School of Engineering Center for Molecular Systems (CMS) Kyushu University 744 Moto-oka, Nishi-ku Fukuoka 819-0395 Japan
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26
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Sasaki Y, Oshikawa M, Bharmoria P, Kouno H, Hayashi-Takagi A, Sato M, Ajioka I, Yanai N, Kimizuka N. Near-Infrared Optogenetic Genome Engineering Based on Photon-Upconversion Hydrogels. Angew Chem Int Ed Engl 2019; 58:17827-17833. [PMID: 31544993 DOI: 10.1002/anie.201911025] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Indexed: 12/16/2022]
Abstract
Photon upconversion (UC) from near-infrared (NIR) light to visible light has enabled optogenetic manipulations in deep tissues. However, materials for NIR optogenetics have been limited to inorganic UC nanoparticles. Herein, NIR-light-triggered optogenetics using biocompatible, organic TTA-UC hydrogels is reported. To achieve triplet sensitization even in highly viscous hydrogel matrices, a NIR-absorbing complex is covalently linked with energy-pooling acceptor chromophores, which significantly elongates the donor triplet lifetime. The donor and acceptor are solubilized in hydrogels formed from biocompatible Pluronic F127 micelles, and heat treatment endows the excited triplets in the hydrogel with remarkable oxygen tolerance. Combined with photoactivatable Cre recombinase technology, NIR-light stimulation successfully performs genome engineering resulting in the formation of dendritic-spine-like structures of hippocampal neurons.
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Affiliation(s)
- Yoichi Sasaki
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Center for Molecular Systems (CMS), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka, 819-0395, Japan
| | - Mio Oshikawa
- Center for Brain Integration Research (CBIR), Tokyo Medical and Dental University (TMDU), 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Pankaj Bharmoria
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Center for Molecular Systems (CMS), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka, 819-0395, Japan
| | - Hironori Kouno
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Center for Molecular Systems (CMS), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka, 819-0395, Japan
| | - Akiko Hayashi-Takagi
- Laboratory of Medical Neuroscience, Institute for Molecular and Cellular Regulation, Gunma University, Maebashi-city, Gunma, 371-8512, Japan.,PRESTO, JST, Honcho 4-1-8, Kawaguchi, Saitama, 332-0012, Japan
| | - Moritoshi Sato
- Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo, 153-8902, Japan
| | - Itsuki Ajioka
- Center for Brain Integration Research (CBIR), Tokyo Medical and Dental University (TMDU), 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan.,PRESTO, JST, Honcho 4-1-8, Kawaguchi, Saitama, 332-0012, Japan
| | - Nobuhiro Yanai
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Center for Molecular Systems (CMS), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka, 819-0395, Japan.,PRESTO, JST, Honcho 4-1-8, Kawaguchi, Saitama, 332-0012, Japan
| | - Nobuo Kimizuka
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Center for Molecular Systems (CMS), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka, 819-0395, Japan
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27
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Mehidi A, Rossier O, Schaks M, Chazeau A, Binamé F, Remorino A, Coppey M, Karatas Z, Sibarita JB, Rottner K, Moreau V, Giannone G. Transient Activations of Rac1 at the Lamellipodium Tip Trigger Membrane Protrusion. Curr Biol 2019; 29:2852-2866.e5. [DOI: 10.1016/j.cub.2019.07.035] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 04/25/2019] [Accepted: 07/11/2019] [Indexed: 01/22/2023]
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28
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Aspenström P. The Intrinsic GDP/GTP Exchange Activities of Cdc42 and Rac1 Are Critical Determinants for Their Specific Effects on Mobilization of the Actin Filament System. Cells 2019; 8:cells8070759. [PMID: 31330900 PMCID: PMC6678527 DOI: 10.3390/cells8070759] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 07/13/2019] [Accepted: 07/18/2019] [Indexed: 12/19/2022] Open
Abstract
The Rho GTPases comprise a subfamily of the Ras superfamily of small GTPases. Their importance in regulation of cell morphology and cell migration is well characterized. According to the prevailing paradigm, Cdc42 regulates the formation of filopodia, Rac1 regulates the formation of lamellipodia, and RhoA triggers the assembly of focal adhesions. However, this scheme is clearly an oversimplification, as the Rho subfamily encompasses 20 members with diverse effects on a number of vital cellular processes, including cytoskeletal dynamics and cell proliferation, migration, and invasion. This article highlights the importance of the catalytic activities of the classical Rho GTPases Cdc42 and Rac1, in terms of their specific effects on the dynamic reorganization of the actin filament system. GTPase-deficient mutants of Cdc42 and Rac1 trigger the formation of broad lamellipodia and stress fibers, and fast-cycling mutations trigger filopodia formation and stress fiber dissolution. The filopodia response requires the involvement of the formin family of actin nucleation promotors. In contrast, the formation of broad lamellipodia induced by GTPase-deficient Cdc42 and Rac1 is mediated through Arp2/3-dependent actin nucleation.
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Affiliation(s)
- Pontus Aspenström
- Rudbeck Laboratory, Department of Immunology, Genetics and Pathology (IGP), Uppsala University, SE 751 85 Uppsala, Sweden.
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29
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Mierke CT. The matrix environmental and cell mechanical properties regulate cell migration and contribute to the invasive phenotype of cancer cells. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2019; 82:064602. [PMID: 30947151 DOI: 10.1088/1361-6633/ab1628] [Citation(s) in RCA: 122] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The minimal structural unit of a solid tumor is a single cell or a cellular compartment such as the nucleus. A closer look inside the cells reveals that there are functional compartments or even structural domains determining the overall properties of a cell such as the mechanical phenotype. The mechanical interaction of these living cells leads to the complex organization such as compartments, tissues and organs of organisms including mammals. In contrast to passive non-living materials, living cells actively respond to the mechanical perturbations occurring in their microenvironment during diseases such as fibrosis and cancer. The transformation of single cancer cells in highly aggressive and hence malignant cancer cells during malignant cancer progression encompasses the basement membrane crossing, the invasion of connective tissue, the stroma microenvironments and transbarrier migration, which all require the immediate interaction of the aggressive and invasive cancer cells with the surrounding extracellular matrix environment including normal embedded neighboring cells. All these steps of the metastatic pathway seem to involve mechanical interactions between cancer cells and their microenvironment. The pathology of cancer due to a broad heterogeneity of cancer types is still not fully understood. Hence it is necessary to reveal the signaling pathways such as mechanotransduction pathways that seem to be commonly involved in the development and establishment of the metastatic and mechanical phenotype in several carcinoma cells. We still do not know whether there exist distinct metastatic genes regulating the progression of tumors. These metastatic genes may then be activated either during the progression of cancer by themselves on their migration path or in earlier stages of oncogenesis through activated oncogenes or inactivated tumor suppressor genes, both of which promote the metastatic phenotype. In more detail, the adhesion of cancer cells to their surrounding stroma induces the generation of intracellular contraction forces that deform their microenvironments by alignment of fibers. The amplitude of these forces can adapt to the mechanical properties of the microenvironment. Moreover, the adhesion strength of cancer cells seems to determine whether a cancer cell is able to migrate through connective tissue or across barriers such as the basement membrane or endothelial cell linings of blood or lymph vessels in order to metastasize. In turn, exposure of adherent cancer cells to physical forces, such as shear flow in vessels or compression forces around tumors, reinforces cell adhesion, regulates cell contractility and restructures the ordering of the local stroma matrix that leads subsequently to secretion of crosslinking proteins or matrix degrading enzymes. Hence invasive cancer cells alter the mechanical properties of their microenvironment. From a mechanobiological point-of-view, the recognized physical signals are transduced into biochemical signaling events that guide cellular responses such as cancer progression after the malignant transition of cancer cells from an epithelial and non-motile phenotype to a mesenchymal and motile (invasive) phenotype providing cellular motility. This transition can also be described as the physical attempt to relate this cancer cell transitional behavior to a T1 phase transition such as the jamming to unjamming transition. During the invasion of cancer cells, cell adaptation occurs to mechanical alterations of the local stroma, such as enhanced stroma upon fibrosis, and therefore we need to uncover underlying mechano-coupling and mechano-regulating functional processes that reinforce the invasion of cancer cells. Moreover, these mechanisms may also be responsible for the awakening of dormant residual cancer cells within the microenvironment. Physicists were initially tempted to consider the steps of the cancer metastasis cascade as single events caused by a single mechanical alteration of the overall properties of the cancer cell. However, this general and simple view has been challenged by the finding that several mechanical properties of cancer cells and their microenvironment influence each other and continuously contribute to tumor growth and cancer progression. In addition, basement membrane crossing, cell invasion and transbarrier migration during cancer progression is explained in physical terms by applying physical principles on living cells regardless of their complexity and individual differences of cancer types. As a novel approach, the impact of the individual microenvironment surrounding cancer cells is also included. Moreover, new theories and models are still needed to understand why certain cancers are malignant and aggressive, while others stay still benign. However, due to the broad variety of cancer types, there may be various pathways solely suitable for specific cancer types and distinct steps in the process of cancer progression. In this review, physical concepts and hypotheses of cancer initiation and progression including cancer cell basement membrane crossing, invasion and transbarrier migration are presented and discussed from a biophysical point-of-view. In addition, the crosstalk between cancer cells and a chronically altered microenvironment, such as fibrosis, is discussed including the basic physical concepts of fibrosis and the cellular responses to mechanical stress caused by the mechanically altered microenvironment. Here, is highlighted how biophysical approaches, both experimentally and theoretically, have an impact on classical hallmarks of cancer and fibrosis and how they contribute to the understanding of the regulation of cancer and its progression by sensing and responding to the physical environmental properties through mechanotransduction processes. Finally, this review discusses various physical models of cell migration such as blebbing, nuclear piston, protrusive force and unjamming transition migration modes and how they contribute to cancer progression. Moreover, these cellular migration modes are influenced by microenvironmental perturbances such as fibrosis that can induce mechanical alterations in cancer cells, which in turn may impact the environment. Hence, the classical hallmarks of cancer need to be refined by including biomechanical properties of cells, cell clusters and tissues and their microenvironment to understand mechano-regulatory processes within cancer cells and the entire organism.
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30
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Schaks M, Singh SP, Kage F, Thomason P, Klünemann T, Steffen A, Blankenfeldt W, Stradal TE, Insall RH, Rottner K. Distinct Interaction Sites of Rac GTPase with WAVE Regulatory Complex Have Non-redundant Functions in Vivo. Curr Biol 2018; 28:3674-3684.e6. [PMID: 30393033 PMCID: PMC6264382 DOI: 10.1016/j.cub.2018.10.002] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Revised: 08/30/2018] [Accepted: 10/01/2018] [Indexed: 12/31/2022]
Abstract
Cell migration often involves the formation of sheet-like lamellipodia generated by branched actin filaments. The branches are initiated when Arp2/3 complex [1] is activated by WAVE regulatory complex (WRC) downstream of small GTPases of the Rac family [2]. Recent structural studies defined two independent Rac binding sites on WRC within the Sra-1/PIR121 subunit of the pentameric WRC [3, 4], but the functions of these sites in vivo have remained unknown. Here we dissect the mechanism of WRC activation and the in vivo relevance of distinct Rac binding sites on Sra-1, using CRISPR/Cas9-mediated gene disruption of Sra-1 and its paralog PIR121 in murine B16-F1 cells combined with Sra-1 mutant rescue. We show that the A site, positioned adjacent to the binding region of WAVE-WCA mediating actin and Arp2/3 complex binding, is the main site for allosteric activation of WRC. In contrast, the D site toward the C terminus is dispensable for WRC activation but required for optimal lamellipodium morphology and function. These results were confirmed in evolutionarily distant Dictyostelium cells. Moreover, the phenotype seen in D site mutants was recapitulated in Rac1 E31 and F37 mutants; we conclude these residues are important for Rac-D site interaction. Finally, constitutively activated WRC was able to induce lamellipodia even after both Rac interaction sites were lost, showing that Rac interaction is not essential for membrane recruitment. Our data establish that physical interaction with Rac is required for WRC activation, in particular through the A site, but is not mandatory for WRC accumulation in the lamellipodium.
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Affiliation(s)
- Matthias Schaks
- Division of Molecular Cell Biology, Zoological Institute, Technische Universität Braunschweig, Spielmannstrasse 7, 38106 Braunschweig, Germany; Cell Biology, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124 Braunschweig, Germany
| | - Shashi P Singh
- CRUK Beatson Institute, Switchback Road, Glasgow G61 1BD, UK; University of Glasgow Institute of Cancer Sciences, Switchback Road, Glasgow G61 1BD, UK
| | - Frieda Kage
- Cell Biology, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124 Braunschweig, Germany
| | - Peter Thomason
- CRUK Beatson Institute, Switchback Road, Glasgow G61 1BD, UK; University of Glasgow Institute of Cancer Sciences, Switchback Road, Glasgow G61 1BD, UK
| | - Thomas Klünemann
- Structure and Function of Proteins, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124 Braunschweig, Germany
| | - Anika Steffen
- Cell Biology, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124 Braunschweig, Germany
| | - Wulf Blankenfeldt
- Structure and Function of Proteins, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124 Braunschweig, Germany
| | - Theresia E Stradal
- Cell Biology, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124 Braunschweig, Germany
| | - Robert H Insall
- CRUK Beatson Institute, Switchback Road, Glasgow G61 1BD, UK; University of Glasgow Institute of Cancer Sciences, Switchback Road, Glasgow G61 1BD, UK.
| | - Klemens Rottner
- Division of Molecular Cell Biology, Zoological Institute, Technische Universität Braunschweig, Spielmannstrasse 7, 38106 Braunschweig, Germany; Cell Biology, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124 Braunschweig, Germany.
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31
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Piniella D, Martínez-Blanco E, Ibáñez I, Bartolomé-Martín D, Porlan E, Díez-Guerra J, Giménez C, Zafra F. Identification of novel regulatory partners of the glutamate transporter GLT-1. Glia 2018; 66:2737-2755. [PMID: 30394597 DOI: 10.1002/glia.23524] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 07/27/2018] [Accepted: 07/30/2018] [Indexed: 01/23/2023]
Abstract
We used proximity-dependent biotin identification (BioID) to find proteins that potentially interact with the major glial glutamate transporter, GLT-1, and we studied how these interactions might affect its activity. GTPase Rac1 was one protein identified, and interfering with its GTP/GDP cycle in mixed primary rat brain cultures affected both the clustering of GLT-1 at the astrocytic processes and the transport kinetics, increasing its uptake activity at low micromolar glutamate concentrations in a manner that was dependent on the effector kinase PAK1 and the actin cytoskeleton. Interestingly, the same manipulations had a different effect on another glial glutamate transporter, GLAST, inhibiting its activity. Importantly, glutamate acts through metabotropic receptors to stimulate the activity of Rac1 in astrocytes, supporting the existence of cross-talk between extracellular glutamate and the astrocytic form of the GLT-1 regulated by Rac1. CDC42EP4/BORG4 (a CDC42 effector) was also identified in the BioID screen, and it is a protein that regulates the assembly of septins and actin fibers, influencing the organization of the cytoskeleton. We found that GLT-1 interacts with septins, which reduces its lateral mobility at the cell surface. Finally, the G-protein subunit GNB4 dampens the activity of GLT-1, as revealed by its response to the activator peptide mSIRK, both in heterologous systems and in primary brain cultures. This effect occurs rapidly and thus, it is unlikely to depend on cytoskeletal dynamics. These novel interactions shed new light on the events controlling GLT-1 activity, thereby helping us to better understand how glutamate homeostasis is maintained in the brain.
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Affiliation(s)
- Dolores Piniella
- Centro de Biología Molecular Severo Ochoa, Facultad de Ciencias, Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, Madrid, Spain.,IdiPAZ, Instituto de Salud Carlos III, Madrid, Spain
| | - Elena Martínez-Blanco
- Centro de Biología Molecular Severo Ochoa, Facultad de Ciencias, Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, Madrid, Spain.,IdiPAZ, Instituto de Salud Carlos III, Madrid, Spain
| | - Ignacio Ibáñez
- Centro de Biología Molecular Severo Ochoa, Facultad de Ciencias, Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, Madrid, Spain.,IdiPAZ, Instituto de Salud Carlos III, Madrid, Spain
| | - David Bartolomé-Martín
- Centro de Biología Molecular Severo Ochoa, Facultad de Ciencias, Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, Madrid, Spain.,IdiPAZ, Instituto de Salud Carlos III, Madrid, Spain
| | - Eva Porlan
- Centro de Biología Molecular Severo Ochoa, Facultad de Ciencias, Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, Madrid, Spain.,IdiPAZ, Instituto de Salud Carlos III, Madrid, Spain
| | - Javier Díez-Guerra
- Centro de Biología Molecular Severo Ochoa, Facultad de Ciencias, Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, Madrid, Spain
| | - Cecilio Giménez
- Centro de Biología Molecular Severo Ochoa, Facultad de Ciencias, Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, Madrid, Spain.,IdiPAZ, Instituto de Salud Carlos III, Madrid, Spain
| | - Francisco Zafra
- Centro de Biología Molecular Severo Ochoa, Facultad de Ciencias, Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, Madrid, Spain.,IdiPAZ, Instituto de Salud Carlos III, Madrid, Spain
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32
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Korobko IV, Shepelev MV. Mutations in the Effector Domain of RhoV GTPase Impair Its Binding to Pak1 Protein Kinase. Mol Biol 2018. [DOI: 10.1134/s002689331804009x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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33
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Borin M, Saraceno C, Catania M, Lorenzetto E, Pontelli V, Paterlini A, Fostinelli S, Avesani A, Di Fede G, Zanusso G, Benussi L, Binetti G, Zorzan S, Ghidoni R, Buffelli M, Bolognin S. Rac1 activation links tau hyperphosphorylation and Aβ dysmetabolism in Alzheimer's disease. Acta Neuropathol Commun 2018; 6:61. [PMID: 30005699 PMCID: PMC6045891 DOI: 10.1186/s40478-018-0567-4] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Accepted: 07/03/2018] [Indexed: 12/22/2022] Open
Abstract
One of the earliest pathological features characterizing Alzheimer’s disease (AD) is the loss of dendritic spines. Among the many factors potentially mediating this loss of neuronal connectivity, the contribution of Rho-GTPases is of particular interest. This family of proteins has been known for years as a key regulator of actin cytoskeleton remodeling. More recent insights have indicated how its complex signaling might be triggered also in pathological conditions. Here, we showed that the Rho-GTPase family member Rac1 levels decreased in the frontal cortex of AD patients compared to non-demented controls. Also, Rac1 increased in plasma samples of AD patients with Mini-Mental State Examination < 18 compared to age-matched non demented controls. The use of different constitutively active peptides allowed us to investigate in vitro Rac1 specific signaling. Its activation increased the processing of amyloid precursor protein and induced the translocation of SET from the nucleus to the cytoplasm, resulting in tau hyperphosphorylation at residue pT181. Notably, Rac1 was abnormally activated in the hippocampus of 6-week-old 3xTg-AD mice. However, the total protein levels decreased at 7-months. A rescue strategy based on the intranasal administration of Rac1 active peptide at 6.5 months prevented dendritic spine loss. This data suggests the intriguing possibility of a dual role of Rac1 according to the different stages of the pathology. In an initial stage, Rac1 deregulation might represent a triggering co-factor due to the direct effect on Aβ and tau. However, at a later stage of the pathology, it might represent a potential therapeutic target due to the beneficial effect on spine dynamics.
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de Groot C, Floriou-Servou A, Tsai YC, Früh S, Kohler M, Parkin G, Schwerdel C, Bosshard G, Kaila K, Fritschy JM, Tyagarajan SK. RhoGEF9 splice isoforms influence neuronal maturation and synapse formation downstream of α2 GABAA receptors. PLoS Genet 2017; 13:e1007073. [PMID: 29069083 PMCID: PMC5673238 DOI: 10.1371/journal.pgen.1007073] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Revised: 11/06/2017] [Accepted: 10/12/2017] [Indexed: 01/11/2023] Open
Abstract
In developing brain neuronal migration, dendrite outgrowth and dendritic spine outgrowth are controlled by Cdc42, a small GTPase of the Rho family, and its activators. Cdc42 function in promoting actin polymerization is crucial for glutamatergic synapse regulation. Here, we focus on GABAergic synapse-specific activator of Cdc42, collybistin (CB) and examine functional differences between its splice isoforms CB1 and CB2. We report that CB1 and CB2 differentially regulate GABAergic synapse formation in vitro along proximal-distal axis and adult-born neuron maturation in vivo. The functional specialization between CB1 and CB2 isoforms arises from their differential protein half-life, in turn regulated by ubiquitin conjugation of the unique CB1 C-terminus. We report that CB1 and CB2 negatively regulate Cdc42; however, Cdc42 activation is dependent on CB interaction with gephyrin. During hippocampal adult neurogenesis CB1 regulates neuronal migration, while CB2 is essential for dendrite outgrowth. Finally, using mice lacking Gabra2 subunit, we show that CB1 function is downstream of GABAARs, and we can rescue adult neurogenesis deficit observed in Gabra2 KO. Overall, our results uncover previously unexpected role for CB isoforms downstream of α2-containing GABAARs during neuron maturation in a Cdc42 dependent mechanism. GABAergic inhibition regulates distinct stages of brain development; however, cellular mechanisms downstream of GABAA receptors (GABAARs) that influence neuronal migration, maturation and synaptogenesis are less clear. ArfGEF9 encodes for RhoGEF with Cdc42 and TC10 GTPase as its substrates. Interestingly, ArhGEF9 is the only known RhoGEF essential for GABAergic synapse formation and maintenance. We report that during brain development ArfGEF9 mRNA splicing regulation generates different ratios of CB1 and CB2 splice isoforms. CB1 mRNA splicing is enhanced during early brain developmental, while CB2 levels remains constant throughout brain development. We also show that CB1 protein has shorter half-life and ubiquitin proteasome system restricts CB1 abundance within developing neuron to modulate neuron migration and distributing GABAergic synapse along the proximal-distal axis. On the other hand, CB2 isoform although expressed abundantly throughout brain development is essential for neuron dendrite maturation. Together, our data identifies specific post-transcriptional and post-translational mechanisms downstream of GABAARs influencing ArhGEF9 function to regulate distinct aspects of neuronal maturation process.
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Affiliation(s)
- Claire de Groot
- Institute of Pharmacology and Toxicology, University of Zurich, Zürich, Switzerland
- Center for Neuroscience Zurich (ZNZ), Zürich, Switzerland
| | | | - Yuan-Chen Tsai
- Institute of Pharmacology and Toxicology, University of Zurich, Zürich, Switzerland
- Center for Neuroscience Zurich (ZNZ), Zürich, Switzerland
| | - Simon Früh
- Institute of Pharmacology and Toxicology, University of Zurich, Zürich, Switzerland
- Center for Neuroscience Zurich (ZNZ), Zürich, Switzerland
| | - Manuela Kohler
- Institute of Pharmacology and Toxicology, University of Zurich, Zürich, Switzerland
| | - Georgia Parkin
- Institute of Pharmacology and Toxicology, University of Zurich, Zürich, Switzerland
| | - Cornelia Schwerdel
- Institute of Pharmacology and Toxicology, University of Zurich, Zürich, Switzerland
| | - Giovanna Bosshard
- Institute of Pharmacology and Toxicology, University of Zurich, Zürich, Switzerland
| | - Kai Kaila
- Neuroscience Center, University of Helsinki, Helsinki, Finland
| | - Jean-Marc Fritschy
- Institute of Pharmacology and Toxicology, University of Zurich, Zürich, Switzerland
- Center for Neuroscience Zurich (ZNZ), Zürich, Switzerland
| | - Shiva K. Tyagarajan
- Institute of Pharmacology and Toxicology, University of Zurich, Zürich, Switzerland
- Center for Neuroscience Zurich (ZNZ), Zürich, Switzerland
- * E-mail:
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Soriano-Castell D, Chavero A, Rentero C, Bosch M, Vidal-Quadras M, Pol A, Enrich C, Tebar F. ROCK1 is a novel Rac1 effector to regulate tubular endocytic membrane formation during clathrin-independent endocytosis. Sci Rep 2017; 7:6866. [PMID: 28761175 PMCID: PMC5537229 DOI: 10.1038/s41598-017-07130-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 06/23/2017] [Indexed: 01/10/2023] Open
Abstract
Clathrin-dependent and -independent pathways contribute for β1-integrin endocytosis. This study defines a tubular membrane clathrin-independent endocytic network, induced with the calmodulin inhibitor W13, for β1-integrin internalization. This pathway is dependent on increased phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) levels and dynamin activity at the plasma membrane. Exogenous addition of PI(4,5)P2 or phosphatidylinositol-4-phosphate 5-kinase (PIP5K) expression mimicked W13-generated-tubules which are inhibited by active Rac1. Therefore, the molecular mechanisms downstream of Rac1, that controls this plasma membrane tubulation, were analyzed biochemically and by the expression of different Rac1 mutants. The results indicate that phospholipase C and ROCK1 are the main Rac1 effectors that impair plasma membrane invagination and tubule formation, essentially by decreasing PI(4,5)P2 levels and promoting cortical actomyosin assembly respectively. Interestingly, among the plethora of proteins that participate in membrane remodeling, this study revealed that ROCK1, the well-known downstream RhoA effector, has an important role in Rac1 regulation of actomyosin at the cell cortex. This study provides new insights into Rac1 functioning on plasma membrane dynamics combining phosphatidylinositides and cytoskeleton regulation.
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Affiliation(s)
- David Soriano-Castell
- Departament de Biomedicina, Unitat de Biologia Cel·lular, Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Facultat de Medicina, Universitat de Barcelona, Casanova 143, 08036, Barcelona, Spain
| | - Albert Chavero
- Departament de Biomedicina, Unitat de Biologia Cel·lular, Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Facultat de Medicina, Universitat de Barcelona, Casanova 143, 08036, Barcelona, Spain
| | - Carles Rentero
- Departament de Biomedicina, Unitat de Biologia Cel·lular, Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Facultat de Medicina, Universitat de Barcelona, Casanova 143, 08036, Barcelona, Spain
| | - Marta Bosch
- Departament de Biomedicina, Unitat de Biologia Cel·lular, Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Facultat de Medicina, Universitat de Barcelona, Casanova 143, 08036, Barcelona, Spain
| | - Maite Vidal-Quadras
- Departament de Biomedicina, Unitat de Biologia Cel·lular, Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Facultat de Medicina, Universitat de Barcelona, Casanova 143, 08036, Barcelona, Spain
| | - Albert Pol
- Departament de Biomedicina, Unitat de Biologia Cel·lular, Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Facultat de Medicina, Universitat de Barcelona, Casanova 143, 08036, Barcelona, Spain.,Institució Catalana de Recerca i Estudis Avançats (ICREA), 08010, Barcelona, Spain
| | - Carlos Enrich
- Departament de Biomedicina, Unitat de Biologia Cel·lular, Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Facultat de Medicina, Universitat de Barcelona, Casanova 143, 08036, Barcelona, Spain
| | - Francesc Tebar
- Departament de Biomedicina, Unitat de Biologia Cel·lular, Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Facultat de Medicina, Universitat de Barcelona, Casanova 143, 08036, Barcelona, Spain.
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Saito M, Otsu W, Hsu KS, Chuang JZ, Yanagisawa T, Shieh V, Kaitsuka T, Wei FY, Tomizawa K, Sung CH. Tctex-1 controls ciliary resorption by regulating branched actin polymerization and endocytosis. EMBO Rep 2017; 18:1460-1472. [PMID: 28607034 DOI: 10.15252/embr.201744204] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Revised: 05/13/2017] [Accepted: 05/16/2017] [Indexed: 11/09/2022] Open
Abstract
The primary cilium is a plasma membrane-protruding sensory organelle that undergoes regulated assembly and resorption. While the assembly process has been studied extensively, the cellular machinery that governs ciliary resorption is less well understood. Previous studies showed that the ciliary pocket membrane is an actin-rich, endocytosis-active periciliary subdomain. Furthermore, Tctex-1, originally identified as a cytoplasmic dynein light chain, has a dynein-independent role in ciliary resorption upon phosphorylation at Thr94. Here, we show that the remodeling and endocytosis of the ciliary pocket membrane are accelerated during ciliary resorption. This process depends on phospho(T94)Tctex-1, actin, and dynamin. Mechanistically, Tctex-1 physically and functionally interacts with the actin dynamics regulators annexin A2, Arp2/3 complex, and Cdc42. Phospho(T94)Tctex-1 is required for Cdc42 activation before the onset of ciliary resorption. Moreover, inhibiting clathrin-dependent endocytosis or suppressing Rab5GTPase on early endosomes effectively abrogates ciliary resorption. Taken together with the epistasis functional assays, our results support a model in which phospho(T94)Tctex-1-regulated actin polymerization and periciliary endocytosis play an active role in orchestrating the initial phase of ciliary resorption.
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Affiliation(s)
- Masaki Saito
- Department of Molecular Pharmacology, Graduate School of Medicine, Tohoku University, Aoba-ku Sendai, Japan .,Department of Cellular Signaling, Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba-ku Sendai, Japan.,Department of Ophthalmology, Margaret M. Dyson Vision Research Institute, Weill Medical College of Cornell University, New York, NY, USA
| | - Wataru Otsu
- Department of Ophthalmology, Margaret M. Dyson Vision Research Institute, Weill Medical College of Cornell University, New York, NY, USA
| | - Kuo-Shun Hsu
- Department of Ophthalmology, Margaret M. Dyson Vision Research Institute, Weill Medical College of Cornell University, New York, NY, USA
| | - Jen-Zen Chuang
- Department of Ophthalmology, Margaret M. Dyson Vision Research Institute, Weill Medical College of Cornell University, New York, NY, USA
| | - Teruyuki Yanagisawa
- Department of Molecular Pharmacology, Graduate School of Medicine, Tohoku University, Aoba-ku Sendai, Japan
| | - Vincent Shieh
- Department of Ophthalmology, Margaret M. Dyson Vision Research Institute, Weill Medical College of Cornell University, New York, NY, USA
| | - Taku Kaitsuka
- Department of Molecular Physiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
| | - Fan-Yan Wei
- Department of Molecular Physiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
| | - Kazuhito Tomizawa
- Department of Molecular Physiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
| | - Ching-Hwa Sung
- Department of Ophthalmology, Margaret M. Dyson Vision Research Institute, Weill Medical College of Cornell University, New York, NY, USA .,Department of Cell and Developmental Biology, Weill Medical College of Cornell University, New York, NY, USA
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Legionella pneumophila prevents proliferation of its natural host Acanthamoeba castellanii. Sci Rep 2016; 6:36448. [PMID: 27805070 PMCID: PMC5091012 DOI: 10.1038/srep36448] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Accepted: 10/14/2016] [Indexed: 12/12/2022] Open
Abstract
Legionella pneumophila is a ubiquitous, pathogenic, Gram-negative bacterium responsible for legionellosis. Like many other amoeba-resistant microorganisms, L. pneumophila resists host clearance and multiplies inside the cell. Through its Dot/Icm type IV secretion system, the bacterium injects more than three hundred effectors that modulate host cell physiology in order to promote its own intracellular replication. Here we report that L. pneumophila prevents proliferation of its natural host Acanthamoeba castellanii. Infected amoebae could not undergo DNA replication and no cell division was observed. The Dot/Icm secretion system was necessary for L. pneumophila to prevent the eukaryotic proliferation. The absence of proliferation was associated with altered amoebal morphology and with a decrease of mRNA transcript levels of CDC2b, a putative regulator of the A. castellanii cell cycle. Complementation of CDC28-deficient Saccharomyces cerevisiae by the CDC2b cDNA was sufficient to restore proliferation of CDC28-deficient S. cerevisiae and suggests for the first time that CDC2b from A. castellanii could be functional and a bona fide cyclin-dependent kinase. Hence, our results reveal that L. pneumophila impairs proliferation of A. castellanii and this effect could involve the cell cycle protein CDC2b.
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38
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Yan JJ, Xie B, Zhang L, Li SJ, van Peer AF, Wu TJ, Chen BZ, Xie BG. Small GTPases and Stress Responses of vvran1 in the Straw Mushroom Volvariella volvacea. Int J Mol Sci 2016; 17:ijms17091527. [PMID: 27626406 PMCID: PMC5037802 DOI: 10.3390/ijms17091527] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 09/05/2016] [Accepted: 09/07/2016] [Indexed: 12/11/2022] Open
Abstract
Small GTPases play important roles in the growth, development and environmental responses of eukaryotes. Based on the genomic sequence of the straw mushroom Volvariella volvacea, 44 small GTPases were identified. A clustering analysis using human small GTPases as the references revealed that V. volvacea small GTPases can be grouped into five families: nine are in the Ras family, 10 are in the Rho family, 15 are in the Rab family, one is in the Ran family and nine are in the Arf family. The transcription of vvran1 was up-regulated upon hydrogen peroxide (H2O2) stress, and could be repressed by diphenyleneiodonium chloride (DPI), a NADPH oxidase-specific inhibitor. The number of vvran1 transcripts also increased upon cold stress. Diphenyleneiodonium chloride, but not the superoxide dismutase (SOD) inhibitor diethy dithiocarbamate (DDC), could suppress the up-regulation of vvran1 gene expression to cold stress. These results combined with the high correlations between gene expression and superoxide anion (O2−) generation indicated that vvran1 could be one of the candidate genes in the downstream of O2− mediated pathways that are generated by NADPH oxidase under low temperature and oxidative stresses.
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Affiliation(s)
- Jun-Jie Yan
- Mycological Research Center, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Bin Xie
- Mycological Research Center, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Lei Zhang
- Mycological Research Center, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Shao-Jie Li
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100080, China.
| | - Arend F van Peer
- Mycological Research Center, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Ta-Ju Wu
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100080, China.
| | - Bing-Zhi Chen
- Mycological Research Center, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Bao-Gui Xie
- Mycological Research Center, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
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Efficient extravasation of tumor-repopulating cells depends on cell deformability. Sci Rep 2016; 6:19304. [PMID: 26787224 PMCID: PMC4726408 DOI: 10.1038/srep19304] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Accepted: 12/09/2015] [Indexed: 12/22/2022] Open
Abstract
Cancer metastasis is the most deadly stage in cancer progression. Despite significant efforts over the past decades, it remains elusive why only a very small fraction of cancer cells is able to generate micrometastasis and metastatic colonization. Recently we have shown that tumor-repopulating cells (TRCs), a highly tumorigenic subpopulation of mouse melanoma cells, can be selected by being cultured and grown in 3D soft fibrin gels. Here we show that when injected into the yolk of a 2 day-post-fertilization (dpf) embryo of Tg (fli1:EGFP or kdrl:mCherry) zebrafish, TRCs are much more efficient in surviving and growing at various secondary sites to generate micrometastasis and metastatic colonization than control melanoma cells that are grown on rigid plastic. The metastasis of TRCs is dependent on the presence of Sox2, a self-renewal gene, and silencing Sox2 leads to the inhibition of TRC metastasis. High-resolution of 3D confocal images of the TRCs at the secondary sites show that extravasation and formation of micrometastases by TRCs are more efficient than by the control cells. Remarkably, efficient extravasation of TRCs in vivo and transmigration in vitro are determined by TRC deformability, as a result of low Cdc42 and high Sox2. Our findings suggest that tumor cell deformability is a key factor in controlling extravasation dynamics during metastasis.
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Zaldua N, Llavero F, Artaso A, Gálvez P, Lacerda HM, Parada LA, Zugaza JL. Rac1/p21‐activated kinase pathway controls retinoblastoma protein phosphorylation and E2F transcription factor activation in B lymphocytes. FEBS J 2016; 283:647-61. [DOI: 10.1111/febs.13617] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Revised: 10/26/2015] [Accepted: 12/01/2015] [Indexed: 12/20/2022]
Affiliation(s)
- Natalia Zaldua
- Center for Cooperative Research in Biosciences Bizkaia Science and Technology Park Spain
- Idem Biotechnology SL Cordovilla Spain
| | - Francisco Llavero
- Department of Genetics, Physical Anthropology and Animal Physiology University of the Basque Country Leioa Spain
- Achucarro Basque Center for Neuroscience Bizkaia Science and Technology Park Spain
| | - Alain Artaso
- Department of Genetics, Physical Anthropology and Animal Physiology University of the Basque Country Leioa Spain
| | - Patricia Gálvez
- Bioiberica Pharmascience Division Technological Park of Health Sciences Granada Spain
| | | | - Luis A. Parada
- Instituto de Patología Experimental CONICET‐Universidad Nacional de Salta Argentina
| | - José L. Zugaza
- Department of Genetics, Physical Anthropology and Animal Physiology University of the Basque Country Leioa Spain
- Achucarro Basque Center for Neuroscience Bizkaia Science and Technology Park Spain
- IKERBASQUE Basque Foundation for Science Bilbao Spain
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Fritz RD, Menshykau D, Martin K, Reimann A, Pontelli V, Pertz O. SrGAP2-Dependent Integration of Membrane Geometry and Slit-Robo-Repulsive Cues Regulates Fibroblast Contact Inhibition of Locomotion. Dev Cell 2015; 35:78-92. [PMID: 26439400 DOI: 10.1016/j.devcel.2015.09.002] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Revised: 08/06/2015] [Accepted: 09/09/2015] [Indexed: 11/17/2022]
Abstract
Migrating fibroblasts undergo contact inhibition of locomotion (CIL), a process that was discovered five decades ago and still is not fully understood at the molecular level. We identify the Slit2-Robo4-srGAP2 signaling network as a key regulator of CIL in fibroblasts. CIL involves highly dynamic contact protrusions with a specialized actin cytoskeleton that stochastically explore cell-cell overlaps between colliding fibroblasts. A membrane curvature-sensing F-BAR domain pre-localizes srGAP2 to protruding edges and terminates their extension phase in response to cell collision. A FRET-based biosensor reveals that Rac1 activity is focused in a band at the tip of contact protrusions, in contrast to the broad activation gradient in contact-free protrusions. SrGAP2 specifically controls the duration of Rac1 activity in contact protrusions, but not in contact-free protrusions. We propose that srGAP2 integrates cell edge curvature and Slit-Robo-mediated repulsive cues to fine-tune Rac1 activation dynamics in contact protrusions to spatiotemporally coordinate CIL.
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Affiliation(s)
- Rafael Dominik Fritz
- Department of Biomedicine, University of Basel, Mattenstrasse 28, 4058 Basel, Switzerland
| | - Denis Menshykau
- Department of Biosystems, Science and Engineering (D-BSSE), ETH Zurich, Mattenstrasse 26, 4058 Basel, Switzerland
| | - Katrin Martin
- Department of Biomedicine, University of Basel, Mattenstrasse 28, 4058 Basel, Switzerland
| | - Andreas Reimann
- Department of Biomedicine, University of Basel, Mattenstrasse 28, 4058 Basel, Switzerland
| | - Valeria Pontelli
- Department of Neurological and Movement Sciences, Section of Physiology, University of Verona, Strada le Grazie 8, 37134 Verona, Italy
| | - Olivier Pertz
- Department of Biomedicine, University of Basel, Mattenstrasse 28, 4058 Basel, Switzerland.
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Lee CC, Huang CC, Hsu KS. The phospholipid-binding protein SESTD1 negatively regulates dendritic spine density by interfering with Rac1-Trio8 signaling pathway. Sci Rep 2015; 5:13250. [PMID: 26272757 PMCID: PMC4536496 DOI: 10.1038/srep13250] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 07/22/2015] [Indexed: 11/09/2022] Open
Abstract
Dendritic spines are actin-rich protrusions from neuronal dendrites that harbor the majority of excitatory synapses. The balance of spine formation and retraction may influence dendritic integrity. While knowledge of the molecular mechanisms that promote dendritic spine formation has accumulated, little is known about the factors that limit spine formation. Here, we show that SESTD1, a phospholipid-binding protein containing a lipid-binding SEC14-like domain and two spectrin-repeat cytoskeleton interaction domains, negatively regulates dendritic spine density in cultured hippocampal neurons. Overexpression of SESTD1 decreases dendritic spine density in neurons by interfering with the interaction between Rac1 and its guanine nucleotide exchange factor (GEF) Trio8. Conversely, knockdown of SESTD1 increases dendritic spine density. Further analysis reveals that the SPEC1 domain-mediated interaction with Rac1 is required for SESTD1 activity toward a decrease in dendritic spine density. Transfection of GEF domain of Trio8 into neurons rescues SESTD1-mediated decrease in dendritic spine density. More importantly, overexpression of SESTD1 results in a decrease in the frequency of miniature excitatory postsynaptic currents (mEPSCs), whereas SESTD1 knockdown increases the mEPSC frequency. These results suggest that SESTD1 may act as a negative regulator of the Rac1-Trio8 signaling pathway to reduce dendritic spine density and lower excitatory synaptic transmission in hippocampal neurons.
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Affiliation(s)
- Cheng-Che Lee
- Department of Pharmacology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Chiung-Chun Huang
- Department of Pharmacology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Kuei-Sen Hsu
- Department of Pharmacology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
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Rouquette-Jazdanian AK, Kortum RL, Li W, Merrill RK, Nguyen PH, Samelson LE, Sommers CL. miR-155 Controls Lymphoproliferation in LAT Mutant Mice by Restraining T-Cell Apoptosis via SHIP-1/mTOR and PAK1/FOXO3/BIM Pathways. PLoS One 2015; 10:e0131823. [PMID: 26121028 PMCID: PMC4487994 DOI: 10.1371/journal.pone.0131823] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Accepted: 06/06/2015] [Indexed: 12/19/2022] Open
Abstract
Linker for Activation of T cells (LAT) is an adapter protein that is essential for T cell function. Knock-in mice with a LAT mutation impairing calcium flux develop a fatal CD4+ lymphoproliferative disease. miR-155 is a microRNA that is correlated with hyperproliferation in a number of cancers including lymphomas and leukemias and is overexpressed in mutant LAT T cells. To test whether miR-155 was merely indicative of T cell activation or whether it contributes to lymphoproliferative disease in mutant LAT mice, we interbred LAT mutant and miR-155-deficient mice. miR-155 deficiency markedly inhibited lymphoproliferative disease by stimulating BIM-dependent CD4+ T cell apoptosis, even though ERK activation and T cell proliferation were increased in double mutant CD4+ T cells. Bim/Bcl2l11 expression is activated by the forkhead transcription factor FOXO3. Using miR-155-deficient, LAT mutant T cells as a discovery tool, we found two connected pathways that impact the nuclear translocation and activation of FOXO3 in T cells. One pathway is mediated by the inositide phosphatase SHIP-1 and the serine/threonine kinases AKT and PDK1. The other pathway involves PAK1 and JNK kinase activation. We define crosstalk between the two pathways via the kinase mTOR, which stabilizes PAK1. This study establishes a role for PAK1 in T cell apoptosis, which contrasts to its previously identified role in T cell proliferation. Furthermore, miR-155 regulates the delicate balance between PAK1-mediated proliferation and apoptosis in T cells impacting lymphoid organ size and function.
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Affiliation(s)
- Alexandre K. Rouquette-Jazdanian
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Robert L. Kortum
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Wenmei Li
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Robert K. Merrill
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Phan H. Nguyen
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Lawrence E. Samelson
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Connie L. Sommers
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
- * E-mail: (CLS)
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Artym VV, Swatkoski S, Matsumoto K, Campbell CB, Petrie RJ, Dimitriadis EK, Li X, Mueller SC, Bugge TH, Gucek M, Yamada KM. Dense fibrillar collagen is a potent inducer of invadopodia via a specific signaling network. ACTA ACUST UNITED AC 2015; 208:331-50. [PMID: 25646088 PMCID: PMC4315243 DOI: 10.1083/jcb.201405099] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
High-density fibrillar collagen matrix induces invadopodia formation in both fibroblasts and carcinoma cell lines through a kindlin2-dependent mechanism that drives local ECM remodeling. Cell interactions with the extracellular matrix (ECM) can regulate multiple cellular activities and the matrix itself in dynamic, bidirectional processes. One such process is local proteolytic modification of the ECM. Invadopodia of tumor cells are actin-rich proteolytic protrusions that locally degrade matrix molecules and mediate invasion. We report that a novel high-density fibrillar collagen (HDFC) matrix is a potent inducer of invadopodia, both in carcinoma cell lines and in primary human fibroblasts. In carcinoma cells, HDFC matrix induced formation of invadopodia via a specific integrin signaling pathway that did not require growth factors or even altered gene and protein expression. In contrast, phosphoproteomics identified major changes in a complex phosphosignaling network with kindlin2 serine phosphorylation as a key regulatory element. This kindlin2-dependent signal transduction network was required for efficient induction of invadopodia on dense fibrillar collagen and for local degradation of collagen. This novel phosphosignaling mechanism regulates cell surface invadopodia via kindlin2 for local proteolytic remodeling of the ECM.
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Affiliation(s)
- Vira V Artym
- Laboratory of Cell and Developmental Biology, National Institute of Dental and Craniofacial Research; Proteomics Core Facility, National Heart, Lung, and Blood Institute; Biomolecular Engineering and Physical Sciences Shared Resource Program, National Institute of Biomolecular Imaging and Bioengineering; Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research; National Institutes of Health, Bethesda, MD 20892 Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical School; and Department of Biostatistics, Bioinformatics, and Biomathematics; Georgetown University, Washington, DC 20057
| | - Stephen Swatkoski
- Laboratory of Cell and Developmental Biology, National Institute of Dental and Craniofacial Research; Proteomics Core Facility, National Heart, Lung, and Blood Institute; Biomolecular Engineering and Physical Sciences Shared Resource Program, National Institute of Biomolecular Imaging and Bioengineering; Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research; National Institutes of Health, Bethesda, MD 20892
| | - Kazue Matsumoto
- Laboratory of Cell and Developmental Biology, National Institute of Dental and Craniofacial Research; Proteomics Core Facility, National Heart, Lung, and Blood Institute; Biomolecular Engineering and Physical Sciences Shared Resource Program, National Institute of Biomolecular Imaging and Bioengineering; Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research; National Institutes of Health, Bethesda, MD 20892
| | - Catherine B Campbell
- Laboratory of Cell and Developmental Biology, National Institute of Dental and Craniofacial Research; Proteomics Core Facility, National Heart, Lung, and Blood Institute; Biomolecular Engineering and Physical Sciences Shared Resource Program, National Institute of Biomolecular Imaging and Bioengineering; Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research; National Institutes of Health, Bethesda, MD 20892
| | - Ryan J Petrie
- Laboratory of Cell and Developmental Biology, National Institute of Dental and Craniofacial Research; Proteomics Core Facility, National Heart, Lung, and Blood Institute; Biomolecular Engineering and Physical Sciences Shared Resource Program, National Institute of Biomolecular Imaging and Bioengineering; Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research; National Institutes of Health, Bethesda, MD 20892
| | - Emilios K Dimitriadis
- Laboratory of Cell and Developmental Biology, National Institute of Dental and Craniofacial Research; Proteomics Core Facility, National Heart, Lung, and Blood Institute; Biomolecular Engineering and Physical Sciences Shared Resource Program, National Institute of Biomolecular Imaging and Bioengineering; Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research; National Institutes of Health, Bethesda, MD 20892
| | - Xin Li
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical School; and Department of Biostatistics, Bioinformatics, and Biomathematics; Georgetown University, Washington, DC 20057
| | - Susette C Mueller
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical School; and Department of Biostatistics, Bioinformatics, and Biomathematics; Georgetown University, Washington, DC 20057
| | - Thomas H Bugge
- Laboratory of Cell and Developmental Biology, National Institute of Dental and Craniofacial Research; Proteomics Core Facility, National Heart, Lung, and Blood Institute; Biomolecular Engineering and Physical Sciences Shared Resource Program, National Institute of Biomolecular Imaging and Bioengineering; Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research; National Institutes of Health, Bethesda, MD 20892
| | - Marjan Gucek
- Laboratory of Cell and Developmental Biology, National Institute of Dental and Craniofacial Research; Proteomics Core Facility, National Heart, Lung, and Blood Institute; Biomolecular Engineering and Physical Sciences Shared Resource Program, National Institute of Biomolecular Imaging and Bioengineering; Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research; National Institutes of Health, Bethesda, MD 20892
| | - Kenneth M Yamada
- Laboratory of Cell and Developmental Biology, National Institute of Dental and Craniofacial Research; Proteomics Core Facility, National Heart, Lung, and Blood Institute; Biomolecular Engineering and Physical Sciences Shared Resource Program, National Institute of Biomolecular Imaging and Bioengineering; Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research; National Institutes of Health, Bethesda, MD 20892
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Nie F, Wang XF, Zhao SY, Bu L, Liu XH. Gene silencing of Rac1 with RNA interference mediated by ultrasound and microbubbles in human LoVo cells: evaluation of cell invasion inhibition and metastatic. J Drug Target 2015; 23:380-6. [PMID: 25673262 DOI: 10.3109/1061186x.2014.1002500] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE The objective of this study was to assess the change of cytoskeleton and cell cycle in LoVo (human colorectal cancer) cell via gene silencing of Rac1 with RNA interference mediated by microbubble (SonoVue) and ultrasound (US). METHODS The compound of plasmid Rac1-shRNA, LoVo cells, and SonoVue was exposed to US (1 MHz, 2 W/cm(2), 5 min). The expression of Rac1 mRNA and Rac1 protein was detected by RT-PCR and Western blot. Cytoskeleton was taken by confocal microscope in a random fashion. Cell invasion was assayed using modified Boyden chambers, and cell cycle and apoptosis were analyzed by flow cytometry in LoVo cells. RESULTS Rac1 gene is overexpressed in human colorectal cancer cells, gene silencing of Rac1 with RNA interference mediated by microbubble and US strongly inhibited lamellipodia formation, cell invasion, and delayed cell cycle, as well as enhanced cell apoptosis of LoVo cells in vitro. CONCLUSION Silencing Rac1 gene mediated by microbubble and US may become a new treatment option for the inhibition of the invasion and metastasis of colorectal cancer cells.
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Affiliation(s)
- Fang Nie
- Department of Medical Ultrasonics, Lanzhou University Second Hospital , Lanzhou, Gansu , China and
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Bopp A, Wartlick F, Henninger C, Schwarz M, Kaina B, Fritz G. Rac1 promotes diethylnitrosamine (DEN)-induced formation of liver tumors. Carcinogenesis 2015; 36:378-89. [PMID: 25556150 DOI: 10.1093/carcin/bgu323] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
To elucidate the function of the Ras-homologous GTPase Rac1 in hepatocarcinogenesis induced by diethylnitrosamine (DEN), mice lacking hepatic Rac1 expression were treated with DEN and compared to the wild-type (WT). Rac1 knock-out (KO) mice were found to have a lower tumor yield as compared to Rac1 proficient mice. The small-sized tumors formed in the absence of Rac1 lack an activated Ras/Raf/mitogen-activated protein kinase pathway, as indicated by the absence of p-ERK expression. Apparently, Rac1 is required for Ras-driven oncogenic pathways. Moreover, tumors in Rac1 deficient mice were glutamine synthase (GS) negative. They displayed a high number of p-H3-positive and cyclinB1 expressing cells, pointing to a defect in mitotic progression. To elucidate the influence of Rac1 on mechanisms of tumor initiation, acute DEN-induced hepatic stress responses were monitored. Rac1 deficiency caused fairly complex, partially time-dependent, alterations in both basal and/or DEN-induced messenger RNA (mRNA) and protein levels of susceptibility-related genes. Basal protein expression of DNA repair factors Brca1 and DNA repair protein RAD51 homolog (Rad51) and the cell cycle regulatory factor p27 was enhanced in the absence of Rac1. Following DEN treatment, p21 mRNA and protein expression was stimulated independent of the Rac1 status. Lack of Rac1 increased mechanisms of the DNA damage response (DDR), as shown by elevated protein levels of p-ATR, p-p53 and γH2AX 24h after DEN treatment. The data show that Rac1 is essential for DEN-stimulated hepatocarcinogenesis. We hypothesize that it promotes tumor initiation by counteracting the elimination of initiated cells and, moreover, alleviates the outgrowth of transformed cells. Hence, pharmacological targeting of Rac1 could be suitable for chemoprevention.
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Affiliation(s)
- Anita Bopp
- Institute of Toxicology, Heinrich Heine University Düsseldorf, Moorenstrasse 5, D-40225 Düsseldorf, Germany
| | - Friedrich Wartlick
- Institute of Toxicology, Heinrich Heine University Düsseldorf, Moorenstrasse 5, D-40225 Düsseldorf, Germany
| | - Christian Henninger
- Institute of Toxicology, Heinrich Heine University Düsseldorf, Moorenstrasse 5, D-40225 Düsseldorf, Germany
| | - Michael Schwarz
- Institute of Pharmacology and Toxicology, University Tübingen, Wilhelmstrasse 76, D-72074 Tübingen, Germany
| | - Bernd Kaina
- Institute of Toxicology, University Medical Center Mainz, Obere Zahlbacher Str. 67, D-55131 Mainz, Germany and
| | - Gerhard Fritz
- Institute of Toxicology, Heinrich Heine University Düsseldorf, Moorenstrasse 5, D-40225 Düsseldorf, Germany,
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Abe T, Yamazaki D, Murakami S, Hiroi M, Nitta Y, Maeyama Y, Tabata T. The NAV2 homolog Sickie regulates F-actin-mediated axonal growth in Drosophila mushroom body neurons via the non-canonical Rac-Cofilin pathway. Development 2014; 141:4716-28. [DOI: 10.1242/dev.113308] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The Rac-Cofilin pathway is essential for cytoskeletal remodeling to control axonal development. Rac signals through the canonical Rac-Pak-LIMK pathway to suppress Cofilin-dependent axonal growth and through a Pak-independent non-canonical pathway to promote outgrowth. Whether this non-canonical pathway converges to promote Cofilin-dependent F-actin reorganization in axonal growth remains elusive. We demonstrate that Sickie, a homolog of the human microtubule-associated protein neuron navigator 2, cell-autonomously regulates axonal growth of Drosophila mushroom body (MB) neurons via the non-canonical pathway. Sickie was prominently expressed in the newborn F-actin-rich axons of MB neurons. A sickie mutant exhibited axonal growth defects, and its phenotypes were rescued by exogenous expression of Sickie. We observed phenotypic similarities and genetic interactions among sickie and Rac-Cofilin signaling components. Using the MARCM technique, distinct F-actin and phospho-Cofilin patterns were detected in developing axons mutant for sickie and Rac-Cofilin signaling regulators. The upregulation of Cofilin function alleviated the axonal defect of the sickie mutant. Epistasis analyses revealed that Sickie suppresses the LIMK overexpression phenotype and is required for Pak-independent Rac1 and Slingshot phosphatase to counteract LIMK. We propose that Sickie regulates F-actin-mediated axonal growth via the non-canonical Rac-Cofilin pathway in a Slingshot-dependent manner.
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Affiliation(s)
- Takashi Abe
- Institute of Molecular and Cellular Biosciences, University of Tokyo, Tokyo 113-0032, Japan
- Graduate Program in Biophysics and Biochemistry, Graduate School of Science, University of Tokyo, Tokyo 113-0033, Japan
| | - Daisuke Yamazaki
- Institute of Molecular and Cellular Biosciences, University of Tokyo, Tokyo 113-0032, Japan
| | - Satoshi Murakami
- Institute of Molecular and Cellular Biosciences, University of Tokyo, Tokyo 113-0032, Japan
| | - Makoto Hiroi
- Institute of Molecular and Cellular Biosciences, University of Tokyo, Tokyo 113-0032, Japan
| | - Yohei Nitta
- Institute of Molecular and Cellular Biosciences, University of Tokyo, Tokyo 113-0032, Japan
| | - Yuko Maeyama
- Institute of Molecular and Cellular Biosciences, University of Tokyo, Tokyo 113-0032, Japan
| | - Tetsuya Tabata
- Institute of Molecular and Cellular Biosciences, University of Tokyo, Tokyo 113-0032, Japan
- Graduate Program in Biophysics and Biochemistry, Graduate School of Science, University of Tokyo, Tokyo 113-0033, Japan
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Devauges V, Matthews DR, Aluko J, Nedbal J, Levitt JA, Poland SP, Coban O, Weitsman G, Monypenny J, Ng T, Ameer-Beg SM. Steady-state acceptor fluorescence anisotropy imaging under evanescent excitation for visualisation of FRET at the plasma membrane. PLoS One 2014; 9:e110695. [PMID: 25360776 PMCID: PMC4215982 DOI: 10.1371/journal.pone.0110695] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Accepted: 09/15/2014] [Indexed: 11/22/2022] Open
Abstract
We present a novel imaging system combining total internal reflection fluorescence (TIRF) microscopy with measurement of steady-state acceptor fluorescence anisotropy in order to perform live cell Förster Resonance Energy Transfer (FRET) imaging at the plasma membrane. We compare directly the imaging performance of fluorescence anisotropy resolved TIRF with epifluorescence illumination. The use of high numerical aperture objective for TIRF required correction for induced depolarization factors. This arrangement enabled visualisation of conformational changes of a Raichu-Cdc42 FRET biosensor by measurement of intramolecular FRET between eGFP and mRFP1. Higher activity of the probe was found at the cell plasma membrane compared to intracellularly. Imaging fluorescence anisotropy in TIRF allowed clear differentiation of the Raichu-Cdc42 biosensor from negative control mutants. Finally, inhibition of Cdc42 was imaged dynamically in live cells, where we show temporal changes of the activity of the Raichu-Cdc42 biosensor.
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Affiliation(s)
- Viviane Devauges
- Richard Dimbleby Cancer Research Laboratory, Division of Cancer Studies and Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom
| | - Daniel R. Matthews
- Richard Dimbleby Cancer Research Laboratory, Division of Cancer Studies and Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom
| | - Justin Aluko
- Department of Physics, King's College London, London, United Kingdom
| | - Jakub Nedbal
- Richard Dimbleby Cancer Research Laboratory, Division of Cancer Studies and Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom
| | - James A. Levitt
- Richard Dimbleby Cancer Research Laboratory, Division of Cancer Studies and Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom
| | - Simon P. Poland
- Richard Dimbleby Cancer Research Laboratory, Division of Cancer Studies and Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom
| | - Oana Coban
- Richard Dimbleby Cancer Research Laboratory, Division of Cancer Studies and Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom
| | - Gregory Weitsman
- Richard Dimbleby Cancer Research Laboratory, Division of Cancer Studies and Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom
| | - James Monypenny
- Richard Dimbleby Cancer Research Laboratory, Division of Cancer Studies and Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom
| | - Tony Ng
- Richard Dimbleby Cancer Research Laboratory, Division of Cancer Studies and Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom
- UCL Cancer Institute, University College London, London, United Kingdom
| | - Simon M. Ameer-Beg
- Richard Dimbleby Cancer Research Laboratory, Division of Cancer Studies and Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom
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Zhao ZS, Manser E. PAK family kinases: Physiological roles and regulation. CELLULAR LOGISTICS 2014; 2:59-68. [PMID: 23162738 PMCID: PMC3490964 DOI: 10.4161/cl.21912] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The p21-activated kinases (PAKs) are a family of Ser/Thr protein kinases that are represented by six genes in humans (PAK 1-6), and are found in all eukaryotes sequenced to date. Genetic and knockdown experiments in frogs, fish and mice indicate group I PAKs are widely expressed, required for multiple tissue development, and particularly important for immune and nervous system function in the adult. The group II PAKs (human PAKs 4-6) are more enigmatic, but their restriction to metazoans and presence at cell-cell junctions suggests these kinases emerged to regulate junctional signaling. Studies of protozoa and fungal PAKs show that they regulate cell shape and polarity through phosphorylation of multiple cytoskeletal proteins, including microtubule binding proteins, myosins and septins. This chapter discusses what we know about the regulation of PAKs and their physiological role in different model organisms, based primarily on gene knockout studies.
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Affiliation(s)
- Zhuo-Shen Zhao
- sGSK Group; Astar Neuroscience Research Partnership; Singapore
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50
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Geiger H, Zheng Y. Regulation of hematopoietic stem cell aging by the small RhoGTPase Cdc42. Exp Cell Res 2014; 329:214-9. [PMID: 25220425 DOI: 10.1016/j.yexcr.2014.09.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Accepted: 09/01/2014] [Indexed: 11/16/2022]
Abstract
Aging of stem cells might be the underlying cause of tissue aging in tissue that in the adult heavily rely on stem cell activity, like the blood forming system. Hematopoiesis, the generation of blood forming cells, is sustained by hematopoietic stem cells. In this review article, we introduce the canonical set of phenotypes associated with aged HSCs, focus on the novel aging-associated phenotype apolarity caused by elevated activity of the small RhoGTPase in aged HSCs, discuss the role of Cdc42 in hematopoiesis and describe that pharmacological inhibition of Cdc42 activity in aged HSCs results in functionally young and thus rejuvenated HSCs.
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Affiliation(s)
- Hartmut Geiger
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children׳s Hospital Medical Center and University of Cincinnati, Cincinnati, OH 45229, USA; Institute for Molecular Medicine, Stem Cells and Aging, Ulm University, Ulm 89091, Germany; aging research center, Ulm University, Ulm, Germany.
| | - Yi Zheng
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children׳s Hospital Medical Center and University of Cincinnati, Cincinnati, OH 45229, USA
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