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Leonov S, Inyang O, Achkasov K, Bogdan E, Kontareva E, Chen Y, Fu Y, Osipov AN, Pustovalova M, Merkher Y. Proteomic Markers for Mechanobiological Properties of Metastatic Cancer Cells. Int J Mol Sci 2023; 24:ijms24054773. [PMID: 36902201 PMCID: PMC10003476 DOI: 10.3390/ijms24054773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 01/26/2023] [Accepted: 02/17/2023] [Indexed: 03/06/2023] Open
Abstract
The major cause (more than 90%) of all cancer-related deaths is metastasis, thus its prediction can critically affect the survival rate. Metastases are currently predicted by lymph-node status, tumor size, histopathology and genetic testing; however, all these are not infallible, and obtaining results may require weeks. The identification of new potential prognostic factors will be an important source of risk information for the practicing oncologist, potentially leading to enhanced patient care through the proactive optimization of treatment strategies. Recently, the new mechanobiology-related techniques, independent of genetics, based on the mechanical invasiveness of cancer cells (microfluidic, gel indentation assays, migration assays etc.), demonstrated a high success rate for the detection of tumor cell metastasis propensity. However, they are still far away from clinical implementation due to complexity. Hence, the exploration of novel markers related to the mechanobiological properties of tumor cells may have a direct impact on the prognosis of metastasis. Our concise review deepens our knowledge of the factors that regulate cancer cell mechanotype and invasion, and incites further studies to develop therapeutics that target multiple mechanisms of invasion for improved clinical benefit. It may open a new clinical dimension that will improve cancer prognosis and increase the effectiveness of tumor therapies.
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Affiliation(s)
- Sergey Leonov
- School of Biological and Medical Physics, Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Moscow Region, Russia
- Institute of Cell Biophysics, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russia
| | - Olumide Inyang
- School of Biological and Medical Physics, Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Moscow Region, Russia
| | - Konstantin Achkasov
- School of Biological and Medical Physics, Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Moscow Region, Russia
| | - Elizaveta Bogdan
- School of Biological and Medical Physics, Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Moscow Region, Russia
| | - Elizaveta Kontareva
- School of Biological and Medical Physics, Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Moscow Region, Russia
| | - Yongheng Chen
- Department of Oncology, NHC Key Laboratory of Cancer Proteomics & State Local Joint Engineering Laboratory for Anticancer Drugs, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha 410008, China
| | - Ying Fu
- Department of Oncology, NHC Key Laboratory of Cancer Proteomics & State Local Joint Engineering Laboratory for Anticancer Drugs, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha 410008, China
| | - Andreyan N. Osipov
- State Research Center—Burnasyan Federal Medical Biophysical Center of Federal Medical-Biological Agency, 123098 Moscow, Russia
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991 Moscow, Russia
- Correspondence:
| | - Margarita Pustovalova
- School of Biological and Medical Physics, Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Moscow Region, Russia
- State Research Center—Burnasyan Federal Medical Biophysical Center of Federal Medical-Biological Agency, 123098 Moscow, Russia
| | - Yulia Merkher
- School of Biological and Medical Physics, Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Moscow Region, Russia
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Mohanraj N, Joshi NS, Poulose R, Patil RR, Santhoshkumar R, Kumar A, Waghmare GP, Saha AK, Haider SZ, Markandeya YS, Dey G, Rao LT, Govindaraj P, Mehta B. A proteomic study to unveil lead toxicity-induced memory impairments invoked by synaptic dysregulation. Toxicol Rep 2022; 9:1501-1513. [DOI: 10.1016/j.toxrep.2022.07.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 07/02/2022] [Accepted: 07/05/2022] [Indexed: 11/17/2022] Open
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Ren Y, He Y, Brown S, Zbornik E, Mlodzianoski MJ, Ma D, Huang F, Mattoo S, Suter DM. A single tyrosine phosphorylation site in cortactin is important for filopodia formation in neuronal growth cones. Mol Biol Cell 2019; 30:1817-1833. [PMID: 31116646 PMCID: PMC6727743 DOI: 10.1091/mbc.e18-04-0202] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Cortactin is a Src tyrosine phosphorylation substrate that regulates multiple actin-related cellular processes. While frequently studied in nonneuronal cells, the functions of cortactin in neuronal growth cones are not well understood. We recently reported that cortactin mediates the effects of Src tyrosine kinase in regulating actin organization and dynamics in both lamellipodia and filopodia of Aplysia growth cones. Here, we identified a single cortactin tyrosine phosphorylation site (Y499) to be important for the formation of filopodia. Overexpression of a 499F phospho-deficient cortactin mutant decreased filopodia length and density, whereas overexpression of a 499E phospho-mimetic mutant increased filopodia length. Using an antibody against cortactin pY499, we showed that tyrosine-phosphorylated cortactin is enriched along the leading edge. The leading edge localization of phosphorylated cortactin is Src2-dependent, F-actin-independent, and important for filopodia formation. In vitro kinase assays revealed that Src2 phosphorylates cortactin at Y499, although Y505 is the preferred site in vitro. Finally, we provide evidence that Arp2/3 complex acts downstream of phosphorylated cortactin to regulate density but not length of filopodia. In conclusion, we have characterized a tyrosine phosphorylation site in Aplysia cortactin that plays a major role in the Src/cortactin/Arp2/3 signaling pathway controlling filopodia formation.
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Affiliation(s)
- Yuan Ren
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907
| | - Yingpei He
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907
| | - Sherlene Brown
- Department of Biochemistry, Purdue University, West Lafayette, IN 47907
| | - Erica Zbornik
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907
| | - Michael J Mlodzianoski
- Department of Weldon School of Biomedical Engineering, Purdue Institutes of Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, IN 47907
| | - Donghan Ma
- Department of Weldon School of Biomedical Engineering, Purdue Institutes of Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, IN 47907
| | - Fang Huang
- Department of Weldon School of Biomedical Engineering, Purdue Institutes of Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, IN 47907.,Department of Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, IN 47907.,Department of Integrative Neuroscience, Purdue University, West Lafayette, IN 47907
| | - Seema Mattoo
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907.,Department of Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, IN 47907
| | - Daniel M Suter
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907.,Department of Integrative Neuroscience, Purdue University, West Lafayette, IN 47907.,Department of Bindley Bioscience Center, Purdue University, West Lafayette, IN 47907.,Department of Birck Nanotechnology Center, Purdue University, West Lafayette, IN 47907
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4
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Parkinson GT, Chamberlain SEL, Jaafari N, Turvey M, Mellor JR, Hanley JG. Cortactin regulates endo-lysosomal sorting of AMPARs via direct interaction with GluA2 subunit. Sci Rep 2018. [PMID: 29515177 PMCID: PMC5841360 DOI: 10.1038/s41598-018-22542-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
AMPA receptor (AMPAR) trafficking is a key determinant of synaptic strength and synaptic plasticity. Under basal conditions, constitutive trafficking maintains surface AMPARs by internalization into the endosomal system, where the majority are sorted and targeted for recycling back to the plasma membrane. NMDA receptor (NMDAR)-dependent Long-Term Depression (LTD) is characterised by a reduction in synaptic strength, and involves endosomal sorting of AMPARs away from recycling pathways to lysosomes. The mechanisms that determine whether AMPARs are trafficked to lysosomes or to recycling endosomes, especially in response to NMDAR stimulation, are unclear. Here, we define a role for the actin-regulatory protein cortactin as a mediator of AMPAR endosomal sorting by direct interaction with the GluA2 subunit. Disrupting GluA2-cortactin binding in neurons causes the targeting of GluA2/A3-containing receptors to lysosomes and their consequent degradation, resulting in a loss of surface and synaptic GluA2 under basal conditions and an occlusion of subsequent LTD expression. Furthermore, we show that NMDAR stimulation causes a dissociation of endogenous cortactin from GluA2 via tyrosine phosphorylation of cortactin. These results demonstrate that cortactin maintains GluA2/A3 levels by directing receptors away from lysosomes, and that disrupting GluA2-cortactin interactions to target GluA2/A3 to lysosomes is an essential component of LTD expression.
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Affiliation(s)
- Gabrielle T Parkinson
- Centre for Synaptic Plasticity and School of Biochemistry, Biomedical Sciences Building, University of Bristol, University Walk, Bristol, BS8, 1TD, UK
| | - Sophie E L Chamberlain
- Centre for Synaptic Plasticity and School of Physiology, Pharmacology & Neuroscience, Biomedical Sciences Building, University of Bristol, University Walk, Bristol, BS8, 1TD, UK
| | - Nadia Jaafari
- Centre for Synaptic Plasticity and School of Biochemistry, Biomedical Sciences Building, University of Bristol, University Walk, Bristol, BS8, 1TD, UK
| | - Matthew Turvey
- Centre for Synaptic Plasticity and School of Biochemistry, Biomedical Sciences Building, University of Bristol, University Walk, Bristol, BS8, 1TD, UK
| | - Jack R Mellor
- Centre for Synaptic Plasticity and School of Physiology, Pharmacology & Neuroscience, Biomedical Sciences Building, University of Bristol, University Walk, Bristol, BS8, 1TD, UK
| | - Jonathan G Hanley
- Centre for Synaptic Plasticity and School of Biochemistry, Biomedical Sciences Building, University of Bristol, University Walk, Bristol, BS8, 1TD, UK.
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Clarke F, Jordan CK, Gutiérrez-Martinez E, Bibby JA, Sanchez-Blanco C, Cornish GH, Dai X, Rawlings DJ, Zamoyska R, Guermonprez P, Cope AP, Purvis HA. Protein tyrosine phosphatase PTPN22 is dispensable for dendritic cell antigen processing and promotion of T-cell activation by dendritic cells. PLoS One 2017; 12:e0186625. [PMID: 29040339 PMCID: PMC5645108 DOI: 10.1371/journal.pone.0186625] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 10/04/2017] [Indexed: 12/21/2022] Open
Abstract
The PTPN22R620W single nucleotide polymorphism increases the risk of developing multiple autoimmune diseases including type 1 diabetes, rheumatoid arthritis and lupus. PTPN22 is highly expressed in antigen presenting cells (APCs) where the expression of the murine disease associated variant orthologue (Ptpn22R619W) is reported to dysregulate pattern recognition receptor signalling in dendritic cells (DCs) and promote T-cell proliferation. Because T-cell activation is dependent on DC antigen uptake, degradation and presentation, we analysed the efficiency of these functions in splenic and GM-CSF bone marrow derived DC from wild type (WT), Ptpn22-/- or Ptpn22R619W mutant mice. Results indicated no differential ability of DCs to uptake antigen via macropinocytosis or receptor-mediated endocytosis. Antigen degradation and presentation was also equal as was WT T-cell conjugate formation and subsequent T-cell proliferation. Despite the likely presence of multiple phosphatase-regulated pathways in the antigen uptake, processing and presentation pathways that we investigated, we observed that Ptpn22 and the R619W autoimmune associated variant were dispensable. These important findings indicate that under non-inflammatory conditions there is no requirement for Ptpn22 in DC dependent antigen uptake and T-cell activation. Our findings reveal that perturbations in antigen uptake and processing, a fundamental pathway determining adaptive immune responses, are unlikely to provide a mechanism for the risk associated with the Ptpn22 autoimmune associated polymorphism.
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Affiliation(s)
- Fiona Clarke
- Academic Department of Rheumatology, Centre for Inflammation Biology and Cancer Immunology, Faculty of Life Sciences and Medicine, King’s College London, London, United Kingdom
| | - Christine K. Jordan
- Academic Department of Rheumatology, Centre for Inflammation Biology and Cancer Immunology, Faculty of Life Sciences and Medicine, King’s College London, London, United Kingdom
| | - Enrique Gutiérrez-Martinez
- Department of Immunobiology, Centre for Inflammation Biology and Cancer Immunology, Faculty of Life Sciences and Medicine, King’s College London, London, United Kingdom
| | - Jack A. Bibby
- Academic Department of Rheumatology, Centre for Inflammation Biology and Cancer Immunology, Faculty of Life Sciences and Medicine, King’s College London, London, United Kingdom
| | - Cristina Sanchez-Blanco
- Academic Department of Rheumatology, Centre for Inflammation Biology and Cancer Immunology, Faculty of Life Sciences and Medicine, King’s College London, London, United Kingdom
| | - Georgina H. Cornish
- Academic Department of Rheumatology, Centre for Inflammation Biology and Cancer Immunology, Faculty of Life Sciences and Medicine, King’s College London, London, United Kingdom
| | - Xuezhi Dai
- Seattle Children’s Research Institute and Departments of Pediatrics and Immunology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - David J. Rawlings
- Seattle Children’s Research Institute and Departments of Pediatrics and Immunology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Rose Zamoyska
- Institute of Immunology and Infection Research, Centre for Immunity, Infection and Evolution, University of Edinburgh, Edinburgh, United Kingdom
| | - Pierre Guermonprez
- Department of Immunobiology, Centre for Inflammation Biology and Cancer Immunology, Faculty of Life Sciences and Medicine, King’s College London, London, United Kingdom
| | - Andrew P. Cope
- Academic Department of Rheumatology, Centre for Inflammation Biology and Cancer Immunology, Faculty of Life Sciences and Medicine, King’s College London, London, United Kingdom
| | - Harriet A. Purvis
- Academic Department of Rheumatology, Centre for Inflammation Biology and Cancer Immunology, Faculty of Life Sciences and Medicine, King’s College London, London, United Kingdom
- * E-mail:
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Zhou C, Ma K, Gao R, Mu C, Chen L, Liu Q, Luo Q, Feng D, Zhu Y, Chen Q. Regulation of mATG9 trafficking by Src- and ULK1-mediated phosphorylation in basal and starvation-induced autophagy. Cell Res 2017; 27:184-201. [PMID: 27934868 PMCID: PMC5339848 DOI: 10.1038/cr.2016.146] [Citation(s) in RCA: 132] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2016] [Revised: 10/13/2016] [Accepted: 10/27/2016] [Indexed: 01/04/2023] Open
Abstract
Autophagy requires diverse membrane sources and involves membrane trafficking of mATG9, the only membrane protein in the ATG family. However, the molecular regulation of mATG9 trafficking for autophagy initiation remains unclear. Here we identified two conserved classic adaptor protein sorting signals within the cytosolic N-terminus of mATG9, which mediate trafficking of mATG9 from the plasma membrane and trans-Golgi network (TGN) via interaction with the AP1/2 complex. Src phosphorylates mATG9 at Tyr8 to maintain its endocytic and constitutive trafficking in unstressed conditions. In response to starvation, phosphorylation of mATG9 at Tyr8 by Src and at Ser14 by ULK1 functionally cooperate to promote interactions between mATG9 and the AP1/2 complex, leading to redistribution of mATG9 from the plasma membrane and juxta-nuclear region to the peripheral pool for autophagy initiation. Our findings uncover novel mechanisms of mATG9 trafficking and suggest a coordination of basal and stress-induced autophagy.
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Affiliation(s)
- Changqian Zhou
- State Key Laboratory of Medicinal Chemical Biology, Tianjin Key Laboratory of Protein Sciences, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Kaili Ma
- State Key Laboratory of Medicinal Chemical Biology, Tianjin Key Laboratory of Protein Sciences, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Ruize Gao
- State Key Laboratory of Medicinal Chemical Biology, Tianjin Key Laboratory of Protein Sciences, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Chenglong Mu
- State Key Laboratory of Medicinal Chemical Biology, Tianjin Key Laboratory of Protein Sciences, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Linbo Chen
- State Key Laboratory of Medicinal Chemical Biology, Tianjin Key Laboratory of Protein Sciences, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Qiangqiang Liu
- State Key Laboratory of Medicinal Chemical Biology, Tianjin Key Laboratory of Protein Sciences, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Qian Luo
- State Key Laboratory of Medicinal Chemical Biology, Tianjin Key Laboratory of Protein Sciences, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Du Feng
- Guangdong Key Laboratory of Age-related Cardiac-cerebral Vascular Disease, Department of Neurology, Institute of Neurology, The Affiliated Hospital of Guangdong Medical University, Guangdong Medical University, Zhanjiang, Guangdong 524001, China
| | - Yushan Zhu
- State Key Laboratory of Medicinal Chemical Biology, Tianjin Key Laboratory of Protein Sciences, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Quan Chen
- State Key Laboratory of Medicinal Chemical Biology, Tianjin Key Laboratory of Protein Sciences, College of Life Sciences, Nankai University, Tianjin 300071, China
- State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
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7
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Watkins RJ, Imruetaicharoenchoke W, Read ML, Sharma N, Poole VL, Gentilin E, Bansal S, Bosseboeuf E, Fletcher R, Nieto HR, Mallick U, Hackshaw A, Mehanna H, Boelaert K, Smith VE, McCabe CJ. Pro-invasive Effect of Proto-oncogene PBF Is Modulated by an Interaction with Cortactin. J Clin Endocrinol Metab 2016; 101:4551-4563. [PMID: 27603901 PMCID: PMC5155689 DOI: 10.1210/jc.2016-1932] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Metastatic disease is responsible for the majority of endocrine cancer deaths. New therapeutic targets are urgently needed to improve patient survival rates. OBJECTIVE The proto-oncogene PTTG1-binding factor (PBF/PTTG1IP) is overexpressed in multiple endocrine cancers and circumstantially associated with tumor aggressiveness. This study aimed to understand the role of PBF in tumor cell invasion and identify possible routes to inhibit its action. Design, Setting, Patients, and Interventions: Thyroid, breast, and colorectal cells were transfected with PBF and cultured for in vitro analysis. PBF and cortactin (CTTN) expression was determined in differentiated thyroid cancer and The Cancer Genome Atlas RNA-seq data. PRIMARY OUTCOME MEASURE Pro-invasive effects of PBF were evaluated by 2D Boyden chamber, 3D organotypic, and proximity ligation assays. RESULTS Our study identified that PBF and CTTN physically interact and co-localize, and that this occurs at the cell periphery, particularly at the leading edge of migrating cancer cells. Critically, PBF induces potent cellular invasion and migration in thyroid and breast cancer cells, which is entirely abrogated in the absence of CTTN. Importantly, we found that CTTN is over-expressed in differentiated thyroid cancer, particularly in patients with regional lymph node metastasis, which significantly correlates with elevated PBF expression. Mutation of PBF (Y174A) or pharmacological intervention modulates the PBF: CTTN interaction and attenuates the invasive properties of cancer cells. CONCLUSION Our results demonstrate a unique role for PBF in regulating CTTN function to promote endocrine cell invasion and migration, as well as identify a new targetable interaction to block tumor cell movement.
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Affiliation(s)
- Rachel J Watkins
- Institute of Metabolism and Systems Research (R.J.W., W.I., M.L.R., N.S., V.L.P., S.B., R.F., H.R.N., K.B., V.E.S., C.J.M.), University of Birmingham, Birmingham B15 2TT, United Kingdom; Department of Surgery, Faculty of Medicine (W.I.), Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; Section of Endocrinology and Internal Medicine (E.G.), University of Ferrara, 44121 Ferrara, Italy; STIM Laboratory (E.B.), University of Poitiers, 86073 Poitiers Cedex 9, France; Northern Centre for Cancer Care (U.M.), Freeman Hospital, Newcastle upon Tyne NE7 7DN, United Kingdom; Cancer Research United Kingdom & UCL Cancer Trials Centre (A.H.), University College London, London WC1E 6BT, United Kingdom; and Institute of Cancer and Genomic Sciences (H.M.), University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Waraporn Imruetaicharoenchoke
- Institute of Metabolism and Systems Research (R.J.W., W.I., M.L.R., N.S., V.L.P., S.B., R.F., H.R.N., K.B., V.E.S., C.J.M.), University of Birmingham, Birmingham B15 2TT, United Kingdom; Department of Surgery, Faculty of Medicine (W.I.), Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; Section of Endocrinology and Internal Medicine (E.G.), University of Ferrara, 44121 Ferrara, Italy; STIM Laboratory (E.B.), University of Poitiers, 86073 Poitiers Cedex 9, France; Northern Centre for Cancer Care (U.M.), Freeman Hospital, Newcastle upon Tyne NE7 7DN, United Kingdom; Cancer Research United Kingdom & UCL Cancer Trials Centre (A.H.), University College London, London WC1E 6BT, United Kingdom; and Institute of Cancer and Genomic Sciences (H.M.), University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Martin L Read
- Institute of Metabolism and Systems Research (R.J.W., W.I., M.L.R., N.S., V.L.P., S.B., R.F., H.R.N., K.B., V.E.S., C.J.M.), University of Birmingham, Birmingham B15 2TT, United Kingdom; Department of Surgery, Faculty of Medicine (W.I.), Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; Section of Endocrinology and Internal Medicine (E.G.), University of Ferrara, 44121 Ferrara, Italy; STIM Laboratory (E.B.), University of Poitiers, 86073 Poitiers Cedex 9, France; Northern Centre for Cancer Care (U.M.), Freeman Hospital, Newcastle upon Tyne NE7 7DN, United Kingdom; Cancer Research United Kingdom & UCL Cancer Trials Centre (A.H.), University College London, London WC1E 6BT, United Kingdom; and Institute of Cancer and Genomic Sciences (H.M.), University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Neil Sharma
- Institute of Metabolism and Systems Research (R.J.W., W.I., M.L.R., N.S., V.L.P., S.B., R.F., H.R.N., K.B., V.E.S., C.J.M.), University of Birmingham, Birmingham B15 2TT, United Kingdom; Department of Surgery, Faculty of Medicine (W.I.), Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; Section of Endocrinology and Internal Medicine (E.G.), University of Ferrara, 44121 Ferrara, Italy; STIM Laboratory (E.B.), University of Poitiers, 86073 Poitiers Cedex 9, France; Northern Centre for Cancer Care (U.M.), Freeman Hospital, Newcastle upon Tyne NE7 7DN, United Kingdom; Cancer Research United Kingdom & UCL Cancer Trials Centre (A.H.), University College London, London WC1E 6BT, United Kingdom; and Institute of Cancer and Genomic Sciences (H.M.), University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Vikki L Poole
- Institute of Metabolism and Systems Research (R.J.W., W.I., M.L.R., N.S., V.L.P., S.B., R.F., H.R.N., K.B., V.E.S., C.J.M.), University of Birmingham, Birmingham B15 2TT, United Kingdom; Department of Surgery, Faculty of Medicine (W.I.), Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; Section of Endocrinology and Internal Medicine (E.G.), University of Ferrara, 44121 Ferrara, Italy; STIM Laboratory (E.B.), University of Poitiers, 86073 Poitiers Cedex 9, France; Northern Centre for Cancer Care (U.M.), Freeman Hospital, Newcastle upon Tyne NE7 7DN, United Kingdom; Cancer Research United Kingdom & UCL Cancer Trials Centre (A.H.), University College London, London WC1E 6BT, United Kingdom; and Institute of Cancer and Genomic Sciences (H.M.), University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Erica Gentilin
- Institute of Metabolism and Systems Research (R.J.W., W.I., M.L.R., N.S., V.L.P., S.B., R.F., H.R.N., K.B., V.E.S., C.J.M.), University of Birmingham, Birmingham B15 2TT, United Kingdom; Department of Surgery, Faculty of Medicine (W.I.), Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; Section of Endocrinology and Internal Medicine (E.G.), University of Ferrara, 44121 Ferrara, Italy; STIM Laboratory (E.B.), University of Poitiers, 86073 Poitiers Cedex 9, France; Northern Centre for Cancer Care (U.M.), Freeman Hospital, Newcastle upon Tyne NE7 7DN, United Kingdom; Cancer Research United Kingdom & UCL Cancer Trials Centre (A.H.), University College London, London WC1E 6BT, United Kingdom; and Institute of Cancer and Genomic Sciences (H.M.), University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Sukhchain Bansal
- Institute of Metabolism and Systems Research (R.J.W., W.I., M.L.R., N.S., V.L.P., S.B., R.F., H.R.N., K.B., V.E.S., C.J.M.), University of Birmingham, Birmingham B15 2TT, United Kingdom; Department of Surgery, Faculty of Medicine (W.I.), Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; Section of Endocrinology and Internal Medicine (E.G.), University of Ferrara, 44121 Ferrara, Italy; STIM Laboratory (E.B.), University of Poitiers, 86073 Poitiers Cedex 9, France; Northern Centre for Cancer Care (U.M.), Freeman Hospital, Newcastle upon Tyne NE7 7DN, United Kingdom; Cancer Research United Kingdom & UCL Cancer Trials Centre (A.H.), University College London, London WC1E 6BT, United Kingdom; and Institute of Cancer and Genomic Sciences (H.M.), University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Emy Bosseboeuf
- Institute of Metabolism and Systems Research (R.J.W., W.I., M.L.R., N.S., V.L.P., S.B., R.F., H.R.N., K.B., V.E.S., C.J.M.), University of Birmingham, Birmingham B15 2TT, United Kingdom; Department of Surgery, Faculty of Medicine (W.I.), Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; Section of Endocrinology and Internal Medicine (E.G.), University of Ferrara, 44121 Ferrara, Italy; STIM Laboratory (E.B.), University of Poitiers, 86073 Poitiers Cedex 9, France; Northern Centre for Cancer Care (U.M.), Freeman Hospital, Newcastle upon Tyne NE7 7DN, United Kingdom; Cancer Research United Kingdom & UCL Cancer Trials Centre (A.H.), University College London, London WC1E 6BT, United Kingdom; and Institute of Cancer and Genomic Sciences (H.M.), University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Rachel Fletcher
- Institute of Metabolism and Systems Research (R.J.W., W.I., M.L.R., N.S., V.L.P., S.B., R.F., H.R.N., K.B., V.E.S., C.J.M.), University of Birmingham, Birmingham B15 2TT, United Kingdom; Department of Surgery, Faculty of Medicine (W.I.), Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; Section of Endocrinology and Internal Medicine (E.G.), University of Ferrara, 44121 Ferrara, Italy; STIM Laboratory (E.B.), University of Poitiers, 86073 Poitiers Cedex 9, France; Northern Centre for Cancer Care (U.M.), Freeman Hospital, Newcastle upon Tyne NE7 7DN, United Kingdom; Cancer Research United Kingdom & UCL Cancer Trials Centre (A.H.), University College London, London WC1E 6BT, United Kingdom; and Institute of Cancer and Genomic Sciences (H.M.), University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Hannah R Nieto
- Institute of Metabolism and Systems Research (R.J.W., W.I., M.L.R., N.S., V.L.P., S.B., R.F., H.R.N., K.B., V.E.S., C.J.M.), University of Birmingham, Birmingham B15 2TT, United Kingdom; Department of Surgery, Faculty of Medicine (W.I.), Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; Section of Endocrinology and Internal Medicine (E.G.), University of Ferrara, 44121 Ferrara, Italy; STIM Laboratory (E.B.), University of Poitiers, 86073 Poitiers Cedex 9, France; Northern Centre for Cancer Care (U.M.), Freeman Hospital, Newcastle upon Tyne NE7 7DN, United Kingdom; Cancer Research United Kingdom & UCL Cancer Trials Centre (A.H.), University College London, London WC1E 6BT, United Kingdom; and Institute of Cancer and Genomic Sciences (H.M.), University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Ujjal Mallick
- Institute of Metabolism and Systems Research (R.J.W., W.I., M.L.R., N.S., V.L.P., S.B., R.F., H.R.N., K.B., V.E.S., C.J.M.), University of Birmingham, Birmingham B15 2TT, United Kingdom; Department of Surgery, Faculty of Medicine (W.I.), Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; Section of Endocrinology and Internal Medicine (E.G.), University of Ferrara, 44121 Ferrara, Italy; STIM Laboratory (E.B.), University of Poitiers, 86073 Poitiers Cedex 9, France; Northern Centre for Cancer Care (U.M.), Freeman Hospital, Newcastle upon Tyne NE7 7DN, United Kingdom; Cancer Research United Kingdom & UCL Cancer Trials Centre (A.H.), University College London, London WC1E 6BT, United Kingdom; and Institute of Cancer and Genomic Sciences (H.M.), University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Allan Hackshaw
- Institute of Metabolism and Systems Research (R.J.W., W.I., M.L.R., N.S., V.L.P., S.B., R.F., H.R.N., K.B., V.E.S., C.J.M.), University of Birmingham, Birmingham B15 2TT, United Kingdom; Department of Surgery, Faculty of Medicine (W.I.), Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; Section of Endocrinology and Internal Medicine (E.G.), University of Ferrara, 44121 Ferrara, Italy; STIM Laboratory (E.B.), University of Poitiers, 86073 Poitiers Cedex 9, France; Northern Centre for Cancer Care (U.M.), Freeman Hospital, Newcastle upon Tyne NE7 7DN, United Kingdom; Cancer Research United Kingdom & UCL Cancer Trials Centre (A.H.), University College London, London WC1E 6BT, United Kingdom; and Institute of Cancer and Genomic Sciences (H.M.), University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Hisham Mehanna
- Institute of Metabolism and Systems Research (R.J.W., W.I., M.L.R., N.S., V.L.P., S.B., R.F., H.R.N., K.B., V.E.S., C.J.M.), University of Birmingham, Birmingham B15 2TT, United Kingdom; Department of Surgery, Faculty of Medicine (W.I.), Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; Section of Endocrinology and Internal Medicine (E.G.), University of Ferrara, 44121 Ferrara, Italy; STIM Laboratory (E.B.), University of Poitiers, 86073 Poitiers Cedex 9, France; Northern Centre for Cancer Care (U.M.), Freeman Hospital, Newcastle upon Tyne NE7 7DN, United Kingdom; Cancer Research United Kingdom & UCL Cancer Trials Centre (A.H.), University College London, London WC1E 6BT, United Kingdom; and Institute of Cancer and Genomic Sciences (H.M.), University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Kristien Boelaert
- Institute of Metabolism and Systems Research (R.J.W., W.I., M.L.R., N.S., V.L.P., S.B., R.F., H.R.N., K.B., V.E.S., C.J.M.), University of Birmingham, Birmingham B15 2TT, United Kingdom; Department of Surgery, Faculty of Medicine (W.I.), Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; Section of Endocrinology and Internal Medicine (E.G.), University of Ferrara, 44121 Ferrara, Italy; STIM Laboratory (E.B.), University of Poitiers, 86073 Poitiers Cedex 9, France; Northern Centre for Cancer Care (U.M.), Freeman Hospital, Newcastle upon Tyne NE7 7DN, United Kingdom; Cancer Research United Kingdom & UCL Cancer Trials Centre (A.H.), University College London, London WC1E 6BT, United Kingdom; and Institute of Cancer and Genomic Sciences (H.M.), University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Vicki E Smith
- Institute of Metabolism and Systems Research (R.J.W., W.I., M.L.R., N.S., V.L.P., S.B., R.F., H.R.N., K.B., V.E.S., C.J.M.), University of Birmingham, Birmingham B15 2TT, United Kingdom; Department of Surgery, Faculty of Medicine (W.I.), Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; Section of Endocrinology and Internal Medicine (E.G.), University of Ferrara, 44121 Ferrara, Italy; STIM Laboratory (E.B.), University of Poitiers, 86073 Poitiers Cedex 9, France; Northern Centre for Cancer Care (U.M.), Freeman Hospital, Newcastle upon Tyne NE7 7DN, United Kingdom; Cancer Research United Kingdom & UCL Cancer Trials Centre (A.H.), University College London, London WC1E 6BT, United Kingdom; and Institute of Cancer and Genomic Sciences (H.M.), University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Christopher J McCabe
- Institute of Metabolism and Systems Research (R.J.W., W.I., M.L.R., N.S., V.L.P., S.B., R.F., H.R.N., K.B., V.E.S., C.J.M.), University of Birmingham, Birmingham B15 2TT, United Kingdom; Department of Surgery, Faculty of Medicine (W.I.), Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; Section of Endocrinology and Internal Medicine (E.G.), University of Ferrara, 44121 Ferrara, Italy; STIM Laboratory (E.B.), University of Poitiers, 86073 Poitiers Cedex 9, France; Northern Centre for Cancer Care (U.M.), Freeman Hospital, Newcastle upon Tyne NE7 7DN, United Kingdom; Cancer Research United Kingdom & UCL Cancer Trials Centre (A.H.), University College London, London WC1E 6BT, United Kingdom; and Institute of Cancer and Genomic Sciences (H.M.), University of Birmingham, Birmingham B15 2TT, United Kingdom
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Janjanam J, Rao GN. Novel role of cortactin in G protein-coupled receptor agonist-induced nuclear export and degradation of p21Cip1. Sci Rep 2016; 6:28687. [PMID: 27363897 DOI: 10.1038/srep28687] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Accepted: 06/08/2016] [Indexed: 12/16/2022] Open
Abstract
Monocyte chemotactic protein 1 (MCP1) stimulates phosphorylation of cortactin on Y421 and Y446 residues in a time-dependent manner and phosphorylation at Y446 but not Y421 residue is required for MCP1-induced CDK-interacting protein 1 (p21Cip1) nuclear export and degradation in facilitating human aortic smooth muscle cell (HASMC) proliferation. In addition, MCP1-induced cortactin tyrosine phosphorylation, p21Cip1 degradation and HASMC proliferation are dependent on Fyn activation. Upstream to Fyn, MCP1 stimulated C-C chemokine receptor type 2 (CCR2) and Gi/o and inhibition of either one of these molecules using their specific antagonists or inhibitors attenuated MCP1-induced cortactin tyrosine phosphorylation, p21Cip1 degradation and HASMC proliferation. Cortactin phosphorylation at Y446 residue is also required for another G protein-coupled receptor (GPCR) agonist, thrombin-induced p21Cip1 nuclear export and its degradation in promoting HASMC proliferation. Quite interestingly, the receptor tyrosine kinase (RTK) agonist, platelet-derived growth factor-BB (PDGF-BB)-induced p21Cip1 degradation and HASMC proliferation do not require cortactin tyrosine phosphorylation. Together, these findings demonstrate that tyrosine phosphorylation of cortactin at Y446 residue is selective for only GPCR but not RTK agonist-induced nuclear export and proteolytic degradation of p21Cip1 in HASMC proliferation.
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Cao H, Schroeder B, Chen J, Schott MB, McNiven MA. The Endocytic Fate of the Transferrin Receptor Is Regulated by c-Abl Kinase. J Biol Chem 2016; 291:16424-37. [PMID: 27226592 PMCID: PMC4974358 DOI: 10.1074/jbc.m116.724997] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Indexed: 12/19/2022] Open
Abstract
Clathrin-mediated endocytosis of transferrin (Tf) and its cognate receptor (TfR1) is a central pathway supporting the uptake of trophic iron. It has generally been assumed that this is a constitutive process. However, we have reported that the non-receptor tyrosine kinase, Src, is activated by Tf to facilitate the internalization of the Tf-TfR1 ligand-receptor complex. As an extension of these findings, we have tested whether subsequent trafficking steps might be regulated by additional kinase-dependent cascades, and we observed a significant endocytic block by inhibiting c-Abl kinase by a variety of methods. Importantly, Tf internalization was reduced significantly in all of these cell models and could be restored by re-expression of WT c-Abl. Surprisingly, this attenuated Tf-TfR1 endocytosis was due to a substantial drop in both the surface and total cellular receptor levels. Additional studies with the LDL receptor showed a similar effect. Surprisingly, immunofluorescence microscopy of imatinib-treated cells revealed a marked colocalization of internalized TfR1 with late endosomes/lysosomes, whereas attenuating the lysosome function with several inhibitors reduced this receptor loss. Importantly, inhibition of c-Abl resulted in a striking redistribution of the chaperone Hsc70 from a diffuse cytosolic localization to an association with the TfR1 at the late endosome-lysosome. Pharmacological inhibition of Hsc70 ATPase activity in cultured cells by the drug VER155008 prevents this chaperone-receptor interaction, resulting in an accumulation of the TfR1 in the early endosome. Thus, inhibition of c-Abl minimizes receptor recycling pathways and results in chaperone-dependent trafficking of the TfR1 to the lysosome for degradation. These findings implicate a novel role for c-Abl and Hsc70 as an unexpected regulator of Hsc70-mediated transport of trophic receptor cargo between the early and late endosomal compartments.
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Affiliation(s)
- Hong Cao
- From the Department of Biochemistry and Molecular Biology, Center for Basic Research in Digestive Diseases, and
| | - Barbara Schroeder
- Department of Experimental Pathology and Laboratory Medicine, Mayo Clinic, Rochester, Minnesota 55905
| | - Jing Chen
- From the Department of Biochemistry and Molecular Biology, Center for Basic Research in Digestive Diseases, and
| | - Micah B Schott
- From the Department of Biochemistry and Molecular Biology, Center for Basic Research in Digestive Diseases, and
| | - Mark A McNiven
- From the Department of Biochemistry and Molecular Biology, Center for Basic Research in Digestive Diseases, and
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Ho N, Gendron RL, Grozinger K, Whelan MA, Hicks EA, Tennakoon B, Gardiner D, Good WV, Paradis H. Tubedown regulation of retinal endothelial permeability signaling pathways. Biol Open 2015; 4:970-9. [PMID: 26142315 PMCID: PMC4542279 DOI: 10.1242/bio.010496] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Tubedown (Tbdn; Naa15), a subunit of the N-terminal acetyltransferase NatA, complexes with the c-Src substrate Cortactin and supports adult retinal homeostasis through regulation of vascular permeability. Here we investigate the role of Tbdn expression on signaling components of retinal endothelial permeability to understand how Tbdn regulates the vasculature and supports retinal homeostasis. Tbdn knockdown-induced hyperpermeability to Albumin in retinal endothelial cells was associated with an increase in the levels of activation of the Src family kinases (SFK) c-Src, Fyn and Lyn and phospho-Cortactin (Tyr421). The knockdown of Cortactin expression reduced Tbdn knockdown-induced permeability to Albumin and the levels of activated SFK. Inhibition of SFK in retinal endothelial cells decreased Tbdn knockdown-induced permeability to Albumin and phospho-Cortactin (Tyr421) levels. Retinal lesions of endothelial-specific Tbdn knockdown mice, with tissue thickening, fibrovascular growth, and hyperpermeable vessels displayed an increase in the levels of activated c-Src. Moreover, the retinal lesions of patients with proliferative diabetic retinopathy (PDR) associated with a loss of Tbdn expression and hyperpermeability to Albumin displayed increased levels of activated SFK in retinal blood vessels. Taken together, these results implicate Tbdn as an important regulator of retinal endothelial permeability and homeostasis by modulating a signaling pathway involving c-Src and Cortactin.
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Affiliation(s)
- Nhu Ho
- Division of BioMedical Sciences, Department of Medicine, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada A1B 3V6
| | - Robert L Gendron
- Division of BioMedical Sciences, Department of Medicine, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada A1B 3V6
| | - Kindra Grozinger
- Division of BioMedical Sciences, Department of Medicine, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada A1B 3V6
| | - Maria A Whelan
- Division of BioMedical Sciences, Department of Medicine, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada A1B 3V6
| | - Emily Anne Hicks
- Division of BioMedical Sciences, Department of Medicine, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada A1B 3V6
| | - Bimal Tennakoon
- Division of BioMedical Sciences, Department of Medicine, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada A1B 3V6
| | - Danielle Gardiner
- Division of BioMedical Sciences, Department of Medicine, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada A1B 3V6
| | - William V Good
- Smith-Kettlewell Eye Research Institute, San Francisco, CA 94115, USA
| | - Hélène Paradis
- Division of BioMedical Sciences, Department of Medicine, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada A1B 3V6
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Reyes-López M, Piña-Vázquez C, Serrano-Luna J. Transferrin: Endocytosis and Cell Signaling in Parasitic Protozoa. Biomed Res Int 2015; 2015:641392. [PMID: 26090431 DOI: 10.1155/2015/641392] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Accepted: 12/18/2014] [Indexed: 12/31/2022]
Abstract
Iron is the fourth most abundant element on Earth and the most abundant metal in the human body. This element is crucial for life because almost all organisms need iron for several biological activities. This is the case with pathogenic organisms, which are at the vanguard in the battle with the human host for iron. The latest regulates Fe concentration through several iron-containing proteins, such as transferrin. The transferrin receptor transports iron to each cell that needs it and maintains it away from pathogens. Parasites have developed several strategies to obtain iron as the expression of specific transferrin receptors localized on plasma membrane, internalized through endocytosis. Signal transduction pathways related to the activation of the receptor have functional importance in proliferation. The study of transferrin receptors and other proteins with action in the signaling networks is important because these proteins could be used as therapeutic targets due to their specificity or to differences with the human counterpart. In this work, we describe proteins that participate in signal transduction processes, especially those that involve transferrin endocytosis, and we compare these processes with those found in T. brucei, T. cruzi, Leishmania spp., and E. histolytica parasites.
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Abstract
GnRH induces marked activation of the actin cytoskeleton in gonadotropes; however, the physiological consequences and cellular mechanisms responsible have yet to be fully elucidated. The current studies focus on the actin scaffolding protein cortactin. Using the gonadotrope-derived αT3-1 cell line, we found that cortactin is phosphorylated at Y(421), S(405), and S(418) in a time-dependent manner in response to the GnRH agonist buserelin (GnRHa). GnRHa induced translocation of cortactin to the leading edge of the plasma membrane where it colocalizes with actin and actin-related protein 3 (Arp3). Incubation of αT3-1 cells with the c-src inhibitor phosphoprotein phosphatase 1, blocked tyrosine phosphorylation of cortactin, reduced cortactin association with Arp3, and blunted actin reorganization in response to GnRHa. Additionally, we used RNA silencing strategies to knock down cortactin in αT3-1 cells. Knockdown of cortactin blocked the ability of αT3-1 cells to generate filopodia, lamellipodia, and membrane ruffles in response to GnRHa. We show that lamellipodia and filopodia are capable of LHβ mobilization in primary pituitary culture after GnRHa treatment, and disruption of these structures using jasplakinolide reduces LH secretion. Collectively, our findings suggest that after GnRHa activation, src activity leads to tyrosine phosphorylation of cortactin, which facilitates its association with Arp3 to engage the actin cytoskeleton. The reorganization of actin by cortactin potentially underlies GnRHa-induced secretory events within αT3-1 cells.
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Affiliation(s)
- Amy M Navratil
- College of Arts and Sciences, Department of Zoology and Physiology (A.M.N., M.G.D.), University of Wyoming, Laramie, Wyoming 82071; College of Veterinary Medicine and Biomedical Science, Departments of Microbiology, Immunology, and Pathology (J.D.W.) and Biomedical Sciences (C.M.C.), Colorado State University, Ft Collins, Colorado, 80523; and College of Veterinary Medicine, Department of Biomedical Sciences (M.S.R.), Cornell University, Ithaca, New York 14853
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Affiliation(s)
- Stacey M MacGrath
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA.
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Chuang Y, Xu X, Kwiatkowska A, Tsapraillis G, Hwang H, Petritis K, Flynn D, Symons M. Regulation of synaptojanin 2 5'-phosphatase activity by Src. Cell Adh Migr 2012; 6:518-25. [PMID: 23076136 PMCID: PMC3547897 DOI: 10.4161/cam.22139] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Synaptojanin 2 (SYNJ2) is a phosphatidylinositol (PI) phosphatase that controls two distinct functions, clathrin-mediated endocytosis and tumor cell invadopodia formation and invasion. Here, we identify a number of novel SYNJ2 binding partners, several of which have previously been shown to be necessary for invadopodia formation or clathrin-mediated endocytosis. We focus on Src family kinases. We found that Src phosphorylates SYNJ2 on Tyr490, thereby stimulating SYNJ2 5′-phosphatase activity in vitro. We also provide evidence that Src-mediated phosphorylation of SYNJ2 contributes to invadopodia formation.
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Affiliation(s)
- Yayu Chuang
- Center for Oncology and Cell Biology, The Feinstein Institute for Medical Research at North Shore-LIJ, Manhasset, NY, USA
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Kelley LC, Weed SA. Cortactin is a substrate of activated Cdc42-associated kinase 1 (ACK1) during ligand-induced epidermal growth factor receptor downregulation. PLoS One 2012; 7:e44363. [PMID: 22952966 PMCID: PMC3431376 DOI: 10.1371/journal.pone.0044363] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2011] [Accepted: 08/06/2012] [Indexed: 12/11/2022] Open
Abstract
Background Epidermal growth factor receptor (EGFR) internalization following ligand binding controls EGFR downstream pathway signaling activity. Internalized EGFR is poly-ubiquitinated by Cbl to promote lysosome-mediated degradation and signal downregulation. ACK1 is a non-receptor tyrosine kinase that interacts with ubiquitinated EGFR to facilitate EGFR degradation. Dynamic reorganization of the cortical actin cytoskeleton controlled by the actin related protein (Arp)2/3 complex is important in regulating EGFR endocytosis and vesicle trafficking. How ACK1-mediated EGFR internalization cooperates with Arp2/3-based actin dynamics during EGFR downregulation is unclear. Methodology/Principal Findings Here we show that ACK1 directly binds and phosphorylates the Arp2/3 regulatory protein cortactin, potentially providing a direct link to Arp2/3-based actin dynamics during EGFR degradation. Co-immunoprecipitation analysis indicates that the cortactin SH3 domain is responsible for binding to ACK1. In vitro kinase assays demonstrate that ACK1 phosphorylates cortactin on key tyrosine residues that create docking sites for adaptor proteins responsible for enhancing Arp2/3 nucleation. Analysis with phosphorylation-specific antibodies determined that EGFR-induced cortactin tyrosine phosphorylation is diminished coincident with EGFR degradation, whereas ERK1/2 cortactin phosphorylation utilized in promoting activation of the Arp2/3 regulator N-WASp is sustained during EGFR downregulation. Cortactin and ACK1 localize to internalized vesicles containing EGF bound to EGFR visualized by confocal microscopy. RNA interference and rescue studies indicate that ACK1 and the cortactin SH3 domain are essential for ligand-mediated EGFR internalization. Conclusions/Significance Cortactin is a direct binding partner and novel substrate of ACK1. Tyrosine phosphorylation of cortactin by ACK1 creates an additional means to amplify Arp2/3 dynamics through N-WASp activation, potentially contributing to the overall necessary tensile and/or propulsive forces utilized during EGFR endocytic internalization and trafficking involved in receptor degradation.
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Affiliation(s)
- Laura C. Kelley
- Department of Neurobiology and Anatomy, Program in Cancer Cell Biology, Mary Babb Randolph Cancer Center, West Virginia University, Morgantown, West Virginia, United States of America
| | - Scott A. Weed
- Department of Neurobiology and Anatomy, Program in Cancer Cell Biology, Mary Babb Randolph Cancer Center, West Virginia University, Morgantown, West Virginia, United States of America
- * E-mail:
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Kirkbride KC, Hong NH, French CL, Clark ES, Jerome WG, Weaver AM. Regulation of late endosomal/lysosomal maturation and trafficking by cortactin affects Golgi morphology. Cytoskeleton (Hoboken) 2012; 69:625-43. [PMID: 22991200 DOI: 10.1002/cm.21051] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2012] [Revised: 07/11/2012] [Accepted: 07/11/2012] [Indexed: 01/23/2023]
Abstract
Cortactin is a branched actin regulator and tumor-overexpressed protein that promotes vesicular trafficking at a variety of cellular sites, including endosomes and the trans-Golgi network. To better understand its role in secretory trafficking, we investigated its function in Golgi homeostasis. Here, we report that knockdown (KD) of cortactin leads to a dramatic change in Golgi morphology by light microscopy, dependent on binding the Arp2/3 actin-nucleating complex. Surprisingly, there was little effect of cortactin-KD on anterograde trafficking of the constitutive cargo vesicular stomatitis virus glycoprotein (VSVG), Golgi assembly from endoplasmic reticulum membranes upon Brefeldin A washout, or Golgi ultrastructure. Instead, electron microscopy studies revealed that cortactin-KD cells contained a large number of immature-appearing late endosomal/lysosomal (LE/Lys) hybrid organelles, similar to those found in lysosomal storage diseases. Consistent with a defect in LE/Lys trafficking, cortactin-KD cells also exhibited accumulation of free cholesterol and retention of the retrograde Golgi cargo mannose-6-phosphate receptor in LE. Inhibition of LE maturation by treatment of control cells with Rab7 siRNA or chloroquine led to a compact Golgi morphology similar to that observed in cortactin-KD cells. Furthermore, the Golgi morphology defects of cortactin-KD cells could be rescued by removal of cholesterol-containing lipids from the media, suggesting that buildup of cholesterol-rich membranes in immature LE/Lys induced disturbances in retrograde trafficking. Taken together, these data reveal that LE/Lys maturation and trafficking are highly sensitive to cortactin-regulated branched actin assembly and suggests that cytoskeletal-induced Golgi morphology changes can be a consequence of altered trafficking at late endosomes.
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Affiliation(s)
- Kellye C Kirkbride
- Department of Cancer Biology, Vanderbilt University Medical Center, Nashville, Tennessee 37232, USA
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Niu S, Wang Z, Ge D, Zhang G, Li Y. Prediction of functional phosphorylation sites by incorporating evolutionary information. Protein Cell 2012; 3:675-90. [PMID: 22802047 DOI: 10.1007/s13238-012-2048-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2012] [Accepted: 06/27/2012] [Indexed: 01/05/2023] Open
Abstract
Protein phosphorylation is a ubiquitous protein post-translational modification, which plays an important role in cellular signaling systems underlying various physiological and pathological processes. Current in silico methods mainly focused on the prediction of phosphorylation sites, but rare methods considered whether a phosphorylation site is functional or not. Since functional phosphorylation sites are more valuable for further experimental research and a proportion of phosphorylation sites have no direct functional effects, the prediction of functional phosphorylation sites is quite necessary for this research area. Previous studies have shown that functional phosphorylation sites are more conserved than non-functional phosphorylation sites in evolution. Thus, in our method, we developed a web server by integrating existing phosphorylation site prediction methods, as well as both absolute and relative evolutionary conservation scores to predict the most likely functional phosphorylation sites. Using our method, we predicted the most likely functional sites of the human, rat and mouse proteomes and built a database for the predicted sites. By the analysis of overall prediction results, we demonstrated that protein phosphorylation plays an important role in all the enriched KEGG pathways. By the analysis of protein-specific prediction results, we demonstrated the usefulness of our method for individual protein studies. Our method would help to characterize the most likely functional phosphorylation sites for further studies in this research area.
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Affiliation(s)
- Shen Niu
- Key Laboratory of Systems Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200031, China
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Sung BH, Zhu X, Kaverina I, Weaver AM. Cortactin controls cell motility and lamellipodial dynamics by regulating ECM secretion. Curr Biol 2011; 21:1460-9. [PMID: 21856159 DOI: 10.1016/j.cub.2011.06.065] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2010] [Revised: 06/22/2011] [Accepted: 07/28/2011] [Indexed: 12/28/2022]
Abstract
BACKGROUND Branched actin assembly is critical for both cell motility and membrane trafficking. The branched actin regulator cortactin is generally considered to promote cell migration by controlling leading-edge lamellipodial dynamics. However, recent reports indicate that lamellipodia are not required for cell movement, suggesting an alternate mechanism. RESULTS Because cortactin also regulates membrane trafficking and adhesion dynamics, we hypothesized that altered secretion of extracellular matrix (ECM) and/or integrin trafficking might underlie motility defects of cortactin-knockdown (KD) cells. Consistent with a primary defect in ECM secretion, both motility and lamellipodial defects of cortactin-KD cells were fully rescued by plating on increasing concentrations of exogenous ECM. Furthermore, cortactin-KD cell speed defects were rescued on cell-free autocrine ECM produced by control cells, but not on ECM produced by cortactin-KD cells. Investigation of the mechanism revealed that whereas endocytosed fibronectin (FN) is redeposited at the basal cell surface by control cells, cortactin-KD cells exhibit defective FN secretion and abnormal FN retention in a late endocytic/lysosomal compartment. Cortactin-KD motility and FN deposition defects were phenocopied by KD in control cells of the lysosomal fusion regulator synaptotagmin-7. Rescue of cortactin-KD cells by expression of cortactin-binding domain mutants revealed that interaction with the Arp2/3 complex and actin filaments is essential for rescue of both cell motility and autocrine ECM secretion phenotypes, whereas binding of SH3-domain partners is not required. CONCLUSIONS Efficient cell motility, promoted by cortactin regulation of branched actin networks, involves processing and resecretion of internalized ECM from a late endosomal/lysosomal compartment.
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Belleudi F, Scrofani C, Torrisi MR, Mancini P. Polarized endocytosis of the keratinocyte growth factor receptor in migrating cells: role of SRC-signaling and cortactin. PLoS One 2011; 6:e29159. [PMID: 22195012 DOI: 10.1371/journal.pone.0029159] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2011] [Accepted: 11/22/2011] [Indexed: 11/19/2022] Open
Abstract
Cell migration is a physiological process that requires endocytic trafficking and polarization of adhesion molecules and receptor tyrosine kinases (RTKs) to the leading edge. Many growth factors are able to induce motility by binding to specific RTK on target cells. Among them, keratinocyte growth factor (KGF or FGF7) and fibroblast growth factor 10 (FGF10), members of the FGF family, are motogenic for keratinocytes, and exert their action by binding to the keratinocyte growth factor receptor (KGFR), a splicing variant of FGFR2, exclusively expressed on epithelial cells. Here we analyzed the possible role of cortactin, an F-actin binding protein which is tyrosine phosphorylated by Src and is involved in KGFR-mediated cell migration, in the KGFR endocytosis and polarization to the leading edge of migrating cells upon ligand-induced stimulation. Biochemical phosphorylation study revealed that both KGF and FGF10 were able to induce tyrosine phosphorylation of Src and in turn of cortactin, as demonstrated by using the specific pharmacological Src-inhibitor SU6656, although FGF10 effect was delayed with respect to that promoted by KGF. Immunofluorescence analysis demonstrated the polarized localization of KGFR upon ligand stimulation to the leading edge of migrating keratinocytes, process that was regulated by Src. Moreover, we showed that the colocalization of cortactin with KGFR at the plasma membrane protrusions and on early endosomes after KGF and FGF10 treatment was Src-dependent. Further, by using a RNA interference approach through microinjection, we showed that cortactin is required for KGFR endocytosis and that the clathrin-dependent internalization of the receptor is a critical event for its polarization. Finally, KGFR expression and polarization enhanced cell migration in a scratch assay. Our results indicate that both Src and cortactin play a key role in the KGFR endocytosis and polarization at the leading edge of migrating keratinocytes, supporting the crucial involvement of RTK trafficking in cell motility.
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Huang Y, Biswas C, Klos Dehring DA, Sriram U, Williamson EK, Li S, Clarke F, Gallucci S, Argon Y, Burkhardt JK. The actin regulatory protein HS1 is required for antigen uptake and presentation by dendritic cells. J Immunol 2011; 187:5952-63. [PMID: 22031761 DOI: 10.4049/jimmunol.1100870] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The hematopoietic actin regulatory protein hematopoietic lineage cell-specific protein 1 (HS1) is required for cell spreading and signaling in lymphocytes, but the scope of HS1 function in Ag presentation has not been addressed. We show that dendritic cells (DCs) from HS1(-/-) mice differentiate normally and display normal LPS-induced upregulation of surface markers and cytokines. Consistent with their normal expression of MHC and costimulatory molecules, HS1(-/-) DCs present OVA peptide efficiently to CD4(+) T cells. However, presentation of OVA protein is defective. Similarly, MHC class I-dependent presentation of VSV8 peptide to CD8(+) T cells occurs normally, but cross-presentation of GRP94/VSV8 complexes is defective. Analysis of Ag uptake pathways shows that HS1 is required for receptor-mediated endocytosis, but not for phagocytosis or macropinocytosis. HS1 interacts with dynamin 2, a protein involved in scission of endocytic vesicles. However, HS1(-/-) DCs showed decreased numbers of endocytic invaginations, whereas dynamin-inhibited cells showed accumulation of these endocytic intermediates. Taken together, these studies show that HS1 promotes an early step in the endocytic pathway that is required for efficient Ag presentation of exogenous Ag by DCs.
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Affiliation(s)
- Yanping Huang
- Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia and Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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21
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Kelley LC, Hayes KE, Ammer AG, Martin KH, Weed SA. Revisiting the ERK/Src cortactin switch. Commun Integr Biol 2011; 4:205-7. [PMID: 21655441 DOI: 10.4161/cib.4.2.14420] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2010] [Accepted: 12/07/2010] [Indexed: 11/19/2022] Open
Abstract
The filamentous (F)-actin regulatory protein cortactin plays an important role in tumor cell movement and invasion by promoting and stabilizing actin related protein (Arp)2/3-mediated actin networks necessary for plasma membrane protrusion. Cortactin is a substrate for ERK1/2 and Src family kinases, with previous in vitro findings demonstrating ERK1/2 phosphorylation of cortactin as a positive and Src phosphorylation as a negative regulatory event in promoting Arp2/3 activation through neuronal Wiskott Aldrich Syndrome protein (N-WASp). Evidence for this regulatory cortactin "switch" in cells has been hampered due to the lack of phosphorylation-specific antibodies that recognize ERK1/2-phosphorylated cortactin. Our findings with phosphorylation-specific antibodies against these ERK1/2 sites (pS405 and pS418) indicate that cortactin can be co-phosphorylated at 405/418 and tyrosine residues targeted by Src family tyrosine kinases. These results indicate that the ERK/Src cortactin switch is not the sole mechanism by which ERK1/2 and tyrosine phosphorylation events regulate cortactin function in cell systems.
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Affiliation(s)
- Laura C Kelley
- Department of Neurobiology and Anatomy; Program in Cancer Cell Biology; Mary Babb Randolph Cancer Center; West Virginia University, Morgantown, WV USA
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22
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Oser M, Mader CC, Gil-Henn H, Magalhaes M, Bravo-Cordero JJ, Koleske AJ, Condeelis J. Specific tyrosine phosphorylation sites on cortactin regulate Nck1-dependent actin polymerization in invadopodia. J Cell Sci 2011; 123:3662-73. [PMID: 20971703 DOI: 10.1242/jcs.068163] [Citation(s) in RCA: 125] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Invadopodia are matrix-degrading membrane protrusions in invasive carcinoma cells enriched in proteins that regulate actin polymerization. The on-off regulatory switch that initiates actin polymerization in invadopodia requires phosphorylation of tyrosine residues 421, 466, and 482 on cortactin. However, it is unknown which of these cortactin tyrosine phosphorylation sites control actin polymerization. We investigated the contribution of individual tyrosine phosphorylation sites (421, 466, and 482) on cortactin to the regulation of actin polymerization in invadopodia. We provide evidence that the phosphorylation of tyrosines 421 and 466, but not 482, is required for the generation of free actin barbed ends in invadopodia. In addition, these same phosphotyrosines are important for Nck1 recruitment to invadopodia via its SH2 domain, for the direct binding of Nck1 to cortactin in vitro, and for the FRET interaction between Nck1 and cortactin in invadopodia. Furthermore, matrix proteolysis-dependent tumor cell invasion is dramatically inhibited in cells expressing a mutation in phosphotyrosine 421 or 466. Together, these results identify phosphorylation of tyrosines 421 and 466 on cortactin as the crucial residues that regulate Nck1-dependent actin polymerization in invadopodia and tumor cell invasion, and suggest that specifically blocking either tyrosine 421 or 466 phosphorylation might be effective at inhibiting tumor cell invasion in vivo.
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Affiliation(s)
- Matthew Oser
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine of Yeshiva University, Bronx, NY 10461, USA
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23
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Abstract
Branched actin assembly is critical for a variety of cellular processes that underlie cell motility and invasion, including cellular protrusion formation and membrane trafficking. Activation of branched actin assembly occurs at various subcellular locations via site-specific activation of distinct WASp family proteins and the Arp2/3 complex. A key branched actin regulator that promotes cell motility and links signaling, cytoskeletal and membrane trafficking proteins is the Src kinase substrate and Arp2/3 binding protein cortactin. Due to its frequent overexpression in advanced, invasive cancers and its general role in regulating branched actin assembly at multiple cellular locations, cortactin has been the subject of intense study. Recent studies suggest that cortactin has a complex role in cellular migration and invasion, promoting both on-site actin polymerization and modulation of autocrine secretion. Diverse cellular activities may derive from the interaction of cortactin with site-specific binding partners.
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Affiliation(s)
- Kellye C Kirkbride
- Department of Cancer Biology, Vanderbilt University Medical Center, Nashville, TN, USA
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24
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Lavoie JN, Landry MC, Faure RL, Champagne C. Src-family kinase signaling, actin-mediated membrane trafficking and organellar dynamics in the control of cell fate: lessons to be learned from the adenovirus E4orf4 death factor. Cell Signal 2010; 22:1604-14. [PMID: 20417707 DOI: 10.1016/j.cellsig.2010.04.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2010] [Accepted: 04/15/2010] [Indexed: 12/15/2022]
Abstract
Evidence has accumulated that there are different modes of regulated cell death, which share overlapping signaling pathways. Cytoskeletal-dependent inter-organellar communication as a result of protein and lipid trafficking in and out of organelles has emerged as a common, key issue in the regulation of cell death modalities. The movement of proteins and lipids between cell compartments is believed to relay death signals in part through modifications of organelles dynamics. Little is known, however, regarding how trafficking is integrated within stress signaling pathways directing organelle-specific remodeling events. In this review, we discuss emerging evidence supporting a role for regulated changes in actin dynamics and intracellular membrane flow. Based on recent findings using the adenovirus E4orf4 death factor as a probing tool to tackle the mechanistic underpinnings that control alternative modes of cell death, we propose the existence of multifunctional platforms at the endosome-Golgi interface regulated by SFK-signaling. These endosomal platforms could be mobilized during cell activation processes to reorganize cellular membranes and promote inter-organelle signaling.
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Affiliation(s)
- Josée N Lavoie
- Centre de Recherche en Cancérologie de l'Université Laval, L'Hôtel-Dieu de Québec, CRCHUQ, Québec, Canada.
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25
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Abstract
The I-BAR domain–containing protein, missing-in-metastasis, directs cell motility by opposing the endocytic activity of the endophilin–CD2AP–cortactin complex. Although directed cellular migration facilitates the coordinated movement of cells during development and repair, the mechanisms regulating such migration remain poorly understood. Missing-in-metastasis (MIM) is a defining member of the inverse Bin/Amphiphysin/Rvs domain (I-BAR) subfamily of lipid binding, cytoskeletal regulators whose levels are altered in a number of cancers. Here, we provide the first genetic evidence that an I-BAR protein regulates directed cell migration in vivo. Drosophila MIM (dmim) is involved in Drosophila border cell migration, with loss of dmim function resulting in a lack of directional movement by the border cell cluster. In vivo endocytosis assays combined with genetic analyses demonstrate that the dmim product regulates directed cell movement by inhibiting endocytosis and antagonizing the activities of the CD2-associated protein/cortactin complex in these cells. These studies demonstrate that DMIM antagonizes pro-endocytic components to facilitate polarity and localized guidance cue sensing during directional cell migration.
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Affiliation(s)
- Gabriel A Quinones
- Program in Epithelial Biology and Cancer Biology Graduate Program, Stanford University School of Medicine, Stanford, CA 94305, USA
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26
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Abstract
The actin severing protein cofilin is essential for directed cell migration and chemotaxis, in many cell types and is also important for tumor cell invasion during metastasis. Through its severing activity, cofilin increases the number of free barbed ends to initiate actin polymerization for actin-based protrusion in two distinct subcellular compartments in invasive tumor cells: lamellipodia and invadopodia. Cofilin severing activity is tightly regulated and multiple mechanisms are utilized to regulate cofilin activity. In this prospect, we have grouped the primary on/off regulation into two broad categories, both of which are important for inhibiting cofilin from binding to F-actin or G-actin: (1) Blocking cofilin activity by the binding of cofilin to either PI(4,5)P(2) at lamellipodia, or cortactin at invadopodia. (2) Blocking cofilin's ability to bind to actin via serine phosphorylation. Although the literature suggests that these cofilin regulatory mechanisms may be cell-type dependent, we propose the existence of a common cofilin activity cycle in which both operate. In this common cycle, the mechanism used to initiate cofilin activity is determined by the starting point in the cycle in a given subcellular compartment.
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Affiliation(s)
- Matthew Oser
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine of Yeshiva University, Bronx, New York 10461, USA.
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27
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Cao H, Chen J, Krueger EW, McNiven MA. SRC-mediated phosphorylation of dynamin and cortactin regulates the "constitutive" endocytosis of transferrin. Mol Cell Biol 2010; 30:781-92. [PMID: 19995918 DOI: 10.1128/MCB.00330-09] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The mechanisms by which epithelial cells regulate clathrin-mediated endocytosis (CME) of transferrin are poorly defined and generally viewed as a constitutive process that occurs continuously without regulatory constraints. In this study, we demonstrate for the first time that endocytosis of the transferrin receptor is a regulated process that requires activated Src kinase and, subsequently, phosphorylation of two important components of the endocytic machinery, namely, the large GTPase dynamin 2 (Dyn2) and its associated actin-binding protein, cortactin (Cort). To our knowledge these findings are among the first to implicate an Src-mediated endocytic cascade in what was previously presumed to be a nonregulated internalization process.
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Zhu JW, Lu YX, Huang BY, Zhao R, Qin J. A peptide homologous with the amino-terminus of cortactin inhibits the migrative, endocytic and invasive capacity of colon cancer cells. Shijie Huaren Xiaohua Zazhi 2009; 17:3302-3306. [DOI: 10.11569/wcjd.v17.i32.3302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To examine the effects of a peptide homologous with the amino-terminus of cortactin (encoded by the CTTN gene) on the migrative, endocytic and invasive capacity of colon cancer cells.
METHODS: A peptide homologous with the amino-terminus of cortactin was designed, prepared and designated as A-peptide (35 kDa). The peptide was then labeled with Cy5 and transfected into colon cancer HCT-8 cells. Cell migration was examined by scratch wound assay. Cell endocytosis was detected by capture enzyme-linked immunosorbent assay (ELISA). Cell invasive capacity was evaluated by Transwell assay.
RESULTS: The A-peptide was successfully purified, labeled and transfected into HCT-8 cells. Compared to mock-transfected cells, cell migration, endocytosis and invasion were significantly attenuated in cells transfected with the A-peptide. The number of A-peptide-transfected cells migrating into the area of wound was reduced compared with mock-transfected cells. In transferrin internalization assay, the absorbance value was significantly lower in A-peptide-transfected cells than in mock-transfected cells (0.3 vs 1.2, P < 0.05). Moreover, the number of invasive cells counted by Transwell assay was significantly lower in A-peptide-transfected cells than in mock-transfected cells (56 ± 1.3 vs 148 ± 2.5, P < 0.05).
CONCLUSION: The A-peptide has the potential to inhibit invasion and metastasis of colorectal cancer.
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29
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Tonkin EG, Cooper M, Lollini LO, Day-lollini PA, Allard J, Kolaja KL, Platz SJ, Chanda SM. Testicular gene expression profiling following 2-methoxyethanol and 2-ethoxyethanol exposure in male rats reveals abnormal expression of the actin binding protein cortactin in degenerating spermatocytes. Toxicol Lett 2009; 190:193-201. [DOI: 10.1016/j.toxlet.2009.07.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2009] [Revised: 07/18/2009] [Accepted: 07/20/2009] [Indexed: 01/18/2023]
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30
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Takkunen M, Hukkanen M, Liljeström M, Grenman R, Virtanen I. Podosome-like structures of non-invasive carcinoma cells are replaced in epithelial-mesenchymal transition by actin comet-embedded invadopodia. J Cell Mol Med 2009; 14:1569-93. [PMID: 19656240 PMCID: PMC3829022 DOI: 10.1111/j.1582-4934.2009.00868.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Podosomes and invadopodia are actin-based structures at the ventral cell membrane, which have a role in cell adhesion, migration and invasion. Little is known about the differences and dynamics underlying these structures. We studied podosome-like structures of oral squamous carcinoma cells and invadopodia of their invasive variant that has undergone a spontaneous epithelial-mesenchymal transition (EMT). In 3D imaging, podosomes were relatively large structures that enlarged in time, whereas invadopodia of invasive cells remained small, but were more numerous, degraded more extracellular matrix (ECM) and were morphologically strikingly different from podosomes. In live-cell imaging, highly dynamic, invadopodia-embedded actin tails were frequently released and rocketed through the cytoplasm. Resembling invadopodia, we found new club-ended cell extensions in EMT-experienced cells, which contained actin, cortactin, vinculin and MT1-matrix metalloproteinase. These dynamic cell extensions degraded ECM and, in field emission scanning electron microscopy, protruded from the dorsal cell membrane. Plectin, αII-spectrin, talin and focal adhesion kinase immunoreactivities were detected in podosome rings, whereas they were absent from invadopodia. Tensin potentially replaced talin in invadopodia. Integrin α3β1 surrounded both podosomes and invadopodia, whereas integrin αvβ5 localized only to invadopodia heads. Pacsin 2, in conjunction with filamin A, was detected early in podosomes, whereas pacsin 2 was not found in invadopodia and filamin A showed delayed accumulation. Fluorescence recovery after photobleaching indicated faster reorganization of actin, cortactin and filamin A in podosomes compared to invadopodia. In conclusion, EMT affects the invasion machinery of oral squamous carcinoma cells. Non-invasive squamous carcinoma cells constitutively organize podosomes, whereas invasive cells form invadopodia. The club-ended cell extensions, or externalized invadopodia, are involved in ECM degradation and maintenance of contact to adhesion substrate and surrounding cells during invasion.
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Affiliation(s)
- Minna Takkunen
- Institute of Biomedicine/Anatomy, University of Helsinki, Helsinki, Finland.
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31
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Lai FPL, Szczodrak M, Oelkers JM, Ladwein M, Acconcia F, Benesch S, Auinger S, Faix J, Small JV, Polo S, Stradal TEB, Rottner K. Cortactin promotes migration and platelet-derived growth factor-induced actin reorganization by signaling to Rho-GTPases. Mol Biol Cell 2009; 20:3209-23. [PMID: 19458196 DOI: 10.1091/mbc.e08-12-1180] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Dynamic actin rearrangements are initiated and maintained by actin filament nucleators, including the Arp2/3-complex. This protein assembly is activated in vitro by distinct nucleation-promoting factors such as Wiskott-Aldrich syndrome protein/Scar family proteins or cortactin, but the relative in vivo functions of each of them remain controversial. Here, we report the conditional genetic disruption of murine cortactin, implicated previously in dynamic actin reorganizations driving lamellipodium protrusion and endocytosis. Unexpectedly, cortactin-deficient cells showed little changes in overall cell morphology and growth. Ultrastructural analyses and live-cell imaging studies revealed unimpaired lamellipodial architecture, Rac-induced protrusion, and actin network turnover, although actin assembly rates in the lamellipodium were modestly increased. In contrast, platelet-derived growth factor-induced actin reorganization and Rac activation were impaired in cortactin null cells. In addition, cortactin deficiency caused reduction of Cdc42 activity and defects in random and directed cell migration. Reduced migration of cortactin null cells could be restored, at least in part, by active Rac and Cdc42 variants. Finally, cortactin removal did not affect the efficiency of receptor-mediated endocytosis. Together, we conclude that cortactin is fully dispensable for Arp2/3-complex activation during lamellipodia protrusion or clathrin pit endocytosis. Furthermore, we propose that cortactin promotes cell migration indirectly, through contributing to activation of selected Rho-GTPases.
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Affiliation(s)
- Frank P L Lai
- Cytoskeleton Dynamics Group, Helmholtz Centre for Infection Research, D-38124 Braunschweig, Germany
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32
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Abstract
AIM: To examine the role of Cortactin in motility and invasive ability of human colon cancer cells.
METHODS: HT-29 colon cancer cells were cultured and treated with Cortactin siRNA. After treatment, the expression level of Cortactin was detected by western blot assay and the expression in cells was assayed under confocal. For test, cells were seeded in 6-well plates and the spreading of cancers was observed. Furthermore, cells were seeded into chambers coated with collagen, and the migration and invasiveness were examined by counting the cells passing through the mini pores on chamber.
RESULTS: Cortactin in cancer cells were knocked down dramatically. The cancer cells treated with Cortactin siRNA demonstrated a postponed spreading, less migration and attenuated invasive ability, compared with cancer cells treated with GFP siRNA. After Cortactin RNAi, the cells that passed through mini-pores was 60 ± 15, while it was 340 ± 45 in the control group (P < 0.01).
CONCLUSION: Cortactin might play an important role in invasion and metastasis of colon cancer.
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33
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Robertson AS, Smythe E, Ayscough KR. Functions of actin in endocytosis. Cell Mol Life Sci 2009; 66:2049-65. [DOI: 10.1007/s00018-009-0001-y] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2009] [Revised: 02/10/2009] [Accepted: 02/13/2009] [Indexed: 12/30/2022]
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Abstract
Since its discovery in the early 1990's, cortactin has emerged as a key signaling protein in many cellular processes, including cell adhesion, migration, endocytosis, and tumor invasion. While the list of cellular functions influenced by cortactin grows, the ability of cortactin to interact with and alter the cortical actin network is central to its role in regulating these processes. Recently, several advances have been made in our understanding of the interaction between actin and cortactin, providing insight into how these two proteins work together to provide a framework for normal and altered cellular function. This review examines how regulation of cortactin through post-translational modifications and interactions with multiple binding partners elicits changes in cortical actin cytoskeletal organization, impacting the regulation and formation of actin-rich motility structures.
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Affiliation(s)
- Amanda Gatesman Ammer
- Department of Neuroscience and Anatomy, Program in Cancer Cell Biology, Mary Babb Randolph Cancer Center, West Virginia University, Morgantown, West Virginia 26506-9300, USA
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35
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Kruchten AE, Krueger EW, Wang Y, McNiven MA. Distinct phospho-forms of cortactin differentially regulate actin polymerization and focal adhesions. Am J Physiol Cell Physiol 2008; 295:C1113-22. [PMID: 18768925 DOI: 10.1152/ajpcell.00238.2008] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Cortactin is an actin-binding protein that is overexpressed in many cancers and is a substrate for both tyrosine and serine/threonine kinases. Tyrosine phosphorylation of cortactin has been observed to increase cell motility and invasion in vivo, although it has been reported to have both positive and negative effects on actin polymerization in vitro. In contrast, serine phosphorylation of cortactin has been shown to stimulate actin assembly in vitro. Currently, the effects of cortactin serine phosphorylation on cell migration are unclear, and furthermore, how the distinct phospho-forms of cortactin may differentially contribute to cell migration has not been directly compared. Therefore, we tested the effects of different tyrosine and serine phospho-mutants of cortactin on lamellipodial protrusion, actin assembly within cells, and focal adhesion dynamics. Interestingly, while expression of either tyrosine or serine phospho-mimetic cortactin mutants resulted in increased lamellipodial protrusion and cell migration, these effects appeared to be via distinct processes. Cortactin mutants mimicking serine phosphorylation appeared to predominantly affect actin polymerization, whereas mutation of cortactin tyrosine residues resulted in alterations in focal adhesion turnover. Thus these findings provide novel insights into how distinct phospho-forms of cortactin may differentially contribute to actin and focal adhesion dynamics to control cell migration.
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Affiliation(s)
- Anne E Kruchten
- Dept. of Biochemistry and Molecular Biology, Mayo Clinic, 200 First St. SW, Guggenheim 1637, Rochester, MN 55905, USA
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36
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Abstract
Invasion of tissues by malignant tumours is facilitated by tumour cell migration and degradation of extracellular matrix (ECM) barriers. Several invasive neoplasms, including head and neck squamous cell carcinoma, breast carcinoma, melanoma and glioma, contain tumour cells that can form actin-rich protrusions with ECM proteolytic activity called invadopodia. These dynamic organelle-like structures adhere to, and digest, collagens, laminins and fibronectin. Invadopodia are dependent on multiple transmembrane, cytoplasmic and secreted proteins engaged in cell adhesion, signal transduction, actin assembly, membrane regulation and ECM proteolysis. Strategies aimed at disrupting invadopodia could form the basis of novel anti-invasive therapies for treating patients. Here we review the molecular basis of invadopodia formation with particular emphasis on the intracellular signaling networks that are essential for invadopodia activity and examine the potential role of these structures in glioma invasion.
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37
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Abstract
Cortactin is a cytoskeletal protein and src kinase substrate that is frequently overexpressed in cancer. Animal studies suggest that cortactin overexpression increases tumor aggressiveness, possibly through promotion of tumor invasion and metastasis. Recently, many studies have documented a role for cortactin in promoting cell motility and invasion, including a critical role in invadopodia, actin rich-subcellular protrusions associated with degradation of the extracellular matrix by cancer cells. Here, I review the evidence and potential mechanisms for cortactin as a critical mediator of tumor cell invasion.
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Affiliation(s)
- Alissa M Weaver
- Department of Cancer Biology, Vanderbilt University Medical Center, 448 PRB, VUMC, Nashville, TN 37232-6840, USA.
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38
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Cowieson NP, King G, Cookson D, Ross I, Huber T, Hume DA, Kobe B, Martin JL. Cortactin adopts a globular conformation and bundles actin into sheets. J Biol Chem 2008; 283:16187-93. [PMID: 18375393 DOI: 10.1074/jbc.m708917200] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cortactin is a filamentous actin-binding protein that plays a pivotal role in translating environmental signals into coordinated rearrangement of the cytoskeleton. The dynamic reorganization of actin in the cytoskeleton drives processes including changes in cell morphology, cell migration, and phagocytosis. In general, structural proteins of the cytoskeleton bind in the N-terminal region of cortactin and regulatory proteins in the C-terminal region. Previous structural studies have reported an extended conformation for cortactin. It is therefore unclear how cortactin facilitates cross-talk between structural proteins and their regulators. In the study presented here, circular dichroism, chemical cross-linking, and small angle x-ray scattering are used to demonstrate that cortactin adopts a globular conformation, thereby bringing distant parts of the molecule into close proximity. In addition, the actin bundling activity of cortactin is characterized, showing that fully polymerized actin filaments are bundled into sheet-like structures. We present a low resolution structure that suggests how the various domains of cortactin interact to coordinate its array of binding partners at sites of actin branching.
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Affiliation(s)
- Nathan P Cowieson
- Institute for Molecular Bioscience and Australian Research Council (ARC) Special Research Centre for Functional and Applied Genomics, University of Queensland, Brisbane QLD 4072 Australia
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39
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Lai FP, Szczodrak M, Block J, Faix J, Breitsprecher D, Mannherz HG, Stradal TE, Dunn GA, Small JV, Rottner K. Arp2/3 complex interactions and actin network turnover in lamellipodia. EMBO J 2008; 27:982-92. [PMID: 18309290 DOI: 10.1038/emboj.2008.34] [Citation(s) in RCA: 227] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2007] [Accepted: 02/07/2008] [Indexed: 11/16/2022] Open
Abstract
Cell migration is initiated by lamellipodia—membrane-enclosed sheets of cytoplasm containing densely packed actin filament networks. Although the molecular details of network turnover remain obscure, recent work points towards key roles in filament nucleation for Arp2/3 complex and its activator WAVE complex. Here, we combine fluorescence recovery after photobleaching (FRAP) of different lamellipodial components with a new method of data analysis to shed light on the dynamics of actin assembly/disassembly. We show that Arp2/3 complex is incorporated into the network exclusively at the lamellipodium tip, like actin, at sites coincident with WAVE complex accumulation. Capping protein likewise showed a turnover similar to actin and Arp2/3 complex, but was confined to the tip. In contrast, cortactin—another prominent Arp2/3 complex regulator—and ADF/cofilin—previously implicated in driving both filament nucleation and disassembly—were rapidly exchanged throughout the lamellipodium. These results suggest that Arp2/3- and WAVE complex-driven actin filament nucleation at the lamellipodium tip is uncoupled from the activities of both cortactin and cofilin. Network turnover is additionally regulated by the spatially segregated activities of capping protein at the tip and cofilin throughout the mesh.
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Ayala I, Baldassarre M, Giacchetti G, Caldieri G, Tetè S, Luini A, Buccione R. Multiple regulatory inputs converge on cortactin to control invadopodia biogenesis and extracellular matrix degradation. J Cell Sci 2008; 121:369-78. [PMID: 18198194 DOI: 10.1242/jcs.008037] [Citation(s) in RCA: 173] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Invadopodia are proteolytically active protrusions formed by invasive tumoral cells when grown on an extracellular matrix (ECM) substratum. Although many molecular components have been defined, less is known of the formation and regulation of invadopodia. The multidomain protein cortactin, which is involved in the regulation of actin polymerisation, is one such component, but how cortactin is modulated to control the formation of invadopodia has not been elucidated. Here, a new invadopodia synchronization protocol is used to show that the cortactin N-terminal acidic and SH3 domains, involved in Arp2/3 complex and N-WASP binding and activation, respectively, are both required for invadopodia biogenesis. In addition, through a combination of RNA interference and a wide array of cortactin phosphorylation mutants, we were able to show that three convergent regulatory inputs based on the regulation of cortactin phosphorylation by Src-family kinases, Erk1/Erk2 and PAK are necessary for invadopodia formation and extracellular matrix degradation. These findings suggest that cortactin is a scaffold protein bringing together the different components necessary for the formation of the invadopodia, and that a fine balance between different phosphorylation events induces subtle changes in structure to calibrate cortactin function.
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Affiliation(s)
- Inmaculada Ayala
- Tumour Cell Invasion Laboratory, Department of Cell Biology and Oncology, Consorzio Mario Negri Sud, S. Maria Imbaro (Chieti), Italy
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Abstract
The Pombe Cdc15 Homology (PCH) proteins have emerged in many species as important coordinators of signaling pathways that regulate actomyosin assembly and membrane dynamics. The hallmark of the PCH proteins is the presence of a Fes/CIP4 homology-Bin/Amphiphysin/Rvsp (F-BAR) domain; therefore they are commonly referred to as F-BAR proteins. The prototype F-BAR protein, Cdc15p of Schizosaccharomyces pombe, has a role in the formation of the contractile actomyosin ring during cytokinesis. Vertebrate F-BAR proteins have an established role in binding phospholipids and they participate in membrane deformations, for instance, during the internalization of transmembrane receptors. This way the F-BAR proteins will function as linkers between the actin polymerization apparatus and the machinery regulating membrane dynamics. Interestingly, some members of the F-BAR proteins are implicated in inflammatory or neurodegenerative disorders and the observations can be expected to have clinical implications for the treatment of the diseases.
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Affiliation(s)
- Pontus Aspenström
- Ludwig Institute for Cancer Research, Uppsala University, SE-751 24 Uppsala, Sweden
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Williams MR, Markey JC, Doczi MA, Morielli AD. An essential role for cortactin in the modulation of the potassium channel Kv1.2. Proc Natl Acad Sci U S A 2007; 104:17412-7. [PMID: 17959782 DOI: 10.1073/pnas.0703865104] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Ion channels are key determinants of membrane excitability. The actin cytoskeleton has a central role in morphology, migration, intracellular transport, and signaling. In this article, we show that the actin-binding protein cortactin regulates the potassium channel Kv1.2 and thereby provides a direct link between actin dynamics and membrane excitability. In previous reports, we showed that the tyrosine phosphorylation-mediated suppression of Kv1.2 ionic current occurs by endocytosis of the channel protein. Pull-down assays using recombinant-purified cortactin and Kv1.2 demonstrated that their interaction is direct and reduced by tyrosine phosphorylation of Kv1.2. This finding suggests a link between cortactin and Kv1.2 endocytosis. Here, we confirm that relationship and identify the molecular mechanisms involved. We use FRET to demonstrate that Kv1.2 and cortactin interact in vivo. By manipulating the cortactin-binding site within Kv1.2, we confirm that cortactin proximity influences channel function. We used flow cytometry in conjunction with cortactin gene replacement to identify C-terminal tyrosines, the fourth repeat actin-binding domain, and the N-terminal Arp2/3-binding region, as critical to Kv1.2 regulation. Surprisingly, cortactin's dynamin-binding Src homology 3 domain is not required for Kv1.2 endocytosis, despite that process being dynamin-dependent. These findings predict that cortactin-mediated actin remodeling in excitable cells is not only important for cell structure, but may directly impact membrane excitability.
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