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Yerneni SS, Solomon T, Smith J, Campbell PG. Radioiodination of extravesicular surface constituents to study the biocorona, cell trafficking and storage stability of extracellular vesicles. Biochim Biophys Acta Gen Subj 2022; 1866:130069. [PMID: 34906563 DOI: 10.1016/j.bbagen.2021.130069] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 10/29/2021] [Accepted: 12/06/2021] [Indexed: 02/08/2023]
Abstract
BACKGROUND Extracellular vesicles (EVs) are produced by all cell types and serve as biological packets delivering a wide variety of molecules for cell-to-cell communication. However, the biology of the EV extravesicular surface domain that we have termed EV 'biocorona' remains underexplored. Upon cell secretion, EVs possess an innate biocorona containing membrane integral and peripheral constituents that is modified by acquired constituents post secretion. This distinguishes EVs from synthetic nanoparticulate biomaterials that are limited to an adsorption-based, acquired biocorona. METHODS The EV biocorona molecular constituents were radiolabeled with 125I to study biocorona constituents and its surface dynamics. As example toolset applications, 125I-EVs were utilized to study EV cell trafficking and the stability of the EV biocorona during storage. RESULTS The biocorona of EVs consisted of proteins, lipids, DNA and RNA. The cellular uptake of 125I-EVs was temperature dependent and internalized 125I-EVs were rapidly recycled by cells. When 125I-EVs were stored in a purified state, they exhibited time and temperature dependent biocorona shedding and proteolytic degradation that was partially inhibited in the presence of serum. CONCLUSION The EV biocorona is complex and dynamic. Radiolabeling of the EV biocorona enables a unique platform methodology to study the biocorona and will facilitate unlocking EV's full clinical translation potential. GENERAL SIGNIFICANCE The EV biocorona affects EV mediated biological processes in health and disease. Acquiring knowledge of the EV biocorona composition, dynamics, stability and structure not only informs the diagnostic and therapeutic translation of EVs but also aids in designing biomimetic nanomaterials for drug delivery.
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Affiliation(s)
- Saigopalakrishna S Yerneni
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA, United States of America
| | - Talia Solomon
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA, United States of America; Department of Chemical Engineering, Carnegie Mellon University, Pittsburgh, PA, United States of America
| | - Jason Smith
- Engineering Research Accelerator, Carnegie Mellon University, Pittsburgh, PA, United States of America
| | - Phil G Campbell
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA, United States of America; Engineering Research Accelerator, Carnegie Mellon University, Pittsburgh, PA, United States of America.
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2
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Beltrán Hernández I, De Groof TWM, Heukers R, Oliveira S. In Vitro Assessment of Binding Affinity, Selectivity, Uptake, Intracellular Degradation, and Toxicity of Nanobody-Photosensitizer Conjugates. Methods Mol Biol 2022; 2451:505-520. [PMID: 35505028 DOI: 10.1007/978-1-0716-2099-1_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Photosensitizers have recently been conjugated to nanobodies for targeted photodynamic therapy (PDT) to selectively kill cancer cells. The success of this approach relies on nanobody-photosensitizer conjugates that bind specifically to their targets with very high affinities (kD in low nM range). Subsequently, upon illumination, these conjugates are very toxic and selective to cells overexpressing the target of interest (EC50 in low nM range). In this chapter, protocols are described to determine the binding affinity of the nanobody-photosensitizer conjugates and assess the toxicity and selectivity of the conjugates when performing in vitro PDT studies. In addition, and because the efficacy of PDT also depends on the (subcellular) localization of the conjugates at the time of illumination, assays are described to investigate the uptake and the intracellular degradation of the nanobody-photosensitizer conjugates.
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Affiliation(s)
- Irati Beltrán Hernández
- Pharmaceutics, Department of Pharmaceutical Sciences, Faculty of Science, Utrecht University, Utrecht, The Netherlands
| | - Timo W M De Groof
- Amsterdam Institute of Molecular and Life Sciences (AIMMS), Division of Medicinal Chemistry, Faculty of Sciences, VU University , Amsterdam, The Netherlands
- In Vivo Cellular and Molecular Imaging Lab, Department of Medical Imaging, Vrije Universiteit Brussel, Brussels, Belgium
| | - Raimond Heukers
- Amsterdam Institute of Molecular and Life Sciences (AIMMS), Division of Medicinal Chemistry, Faculty of Sciences, VU University , Amsterdam, The Netherlands
| | - Sabrina Oliveira
- Pharmaceutics, Department of Pharmaceutical Sciences, Faculty of Science, Utrecht University, Utrecht, The Netherlands.
- Cell Biology, Neurobiology and Biophysics, Department of Biology, Faculty of Science, Utrecht University, Utrecht, The Netherlands.
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3
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Pathomechanisms of ALS8: altered autophagy and defective RNA binding protein (RBP) homeostasis due to the VAPB P56S mutation. Cell Death Dis 2021; 12:466. [PMID: 33972508 PMCID: PMC8110809 DOI: 10.1038/s41419-021-03710-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 04/12/2021] [Accepted: 04/13/2021] [Indexed: 02/03/2023]
Abstract
Mutations in RNA binding proteins (RBPs) and in genes regulating autophagy are frequent causes of familial amyotrophic lateral sclerosis (fALS). The P56S mutation in vesicle-associated membrane protein-associated protein B (VAPB) leads to fALS (ALS8) and spinal muscular atrophy (SMA). While VAPB is primarily involved in the unfolded protein response (UPR), vesicular trafficking and in initial steps of the autophagy pathway, the effect of mutant P56S-VAPB on autophagy regulation in connection with RBP homeostasis has not been explored yet. Examining the muscle biopsy of our index ALS8 patient of European origin revealed globular accumulations of VAPB aggregates co-localised with autophagy markers LC3 and p62 in partially atrophic and atrophic muscle fibres. In line with this skin fibroblasts obtained from the same patient showed accumulation of P56S-VAPB aggregates together with LC3 and p62. Detailed investigations of autophagic flux in cell culture models revealed that P56S-VAPB alters both initial and late steps of the autophagy pathway. Accordingly, electron microscopy complemented with live cell imaging highlighted the impaired fusion of accumulated autophagosomes with lysosomes in cells expressing P56S-VAPB. Consistent with these observations, neuropathological studies of brain and spinal cord of P56S-VAPB transgenic mice revealed signs of neurodegeneration associated with altered protein quality control and defective autophagy. Autophagy and RBP homeostasis are interdependent, as demonstrated by the cytoplasmic mis-localisation of several RBPs including pTDP-43, FUS, Matrin 3 which often sequestered with P56S-VAPB aggregates both in cell culture and in the muscle biopsy of the ALS8 patient. Further confirming the notion that aggregation of the RBPs proceeds through the stress granule (SG) pathway, we found persistent G3BP- and TIAR1-positive SGs in P56S-VAPB expressing cells as well as in the ALS8 patient muscle biopsy. We conclude that P56S-VAPB-ALS8 involves a cohesive pathomechanism of aberrant RBP homeostasis together with dysfunctional autophagy.
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4
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Shen CH, Chou CC, Lai TY, Hsu JE, Lin YS, Liu HY, Chen YK, Ho IL, Hsu PH, Chuang TH, Lee CY, Hsu LC. ZNRF1 Mediates Epidermal Growth Factor Receptor Ubiquitination to Control Receptor Lysosomal Trafficking and Degradation. Front Cell Dev Biol 2021; 9:642625. [PMID: 33996800 PMCID: PMC8118649 DOI: 10.3389/fcell.2021.642625] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 04/08/2021] [Indexed: 11/30/2022] Open
Abstract
Activation of the epidermal growth factor receptor (EGFR) is crucial for development, tissue homeostasis, and immunity. Dysregulation of EGFR signaling is associated with numerous diseases. EGFR ubiquitination and endosomal trafficking are key events that regulate the termination of EGFR signaling, but their underlying mechanisms remain obscure. Here, we reveal that ZNRF1, an E3 ubiquitin ligase, controls ligand-induced EGFR signaling via mediating receptor ubiquitination. Deletion of ZNRF1 inhibits endosome-to-lysosome sorting of EGFR, resulting in delayed receptor degradation and prolonged downstream signaling. We further demonstrate that ZNRF1 and Casitas B-lineage lymphoma (CBL), another E3 ubiquitin ligase responsible for EGFR ubiquitination, mediate ubiquitination at distinct lysine residues on EGFR. Furthermore, loss of ZNRF1 results in increased susceptibility to herpes simplex virus 1 (HSV-1) infection due to enhanced EGFR-dependent viral entry. Our findings identify ZNRF1 as a novel regulator of EGFR signaling, which together with CBL controls ligand-induced EGFR ubiquitination and lysosomal trafficking.
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Affiliation(s)
- Chia-Hsing Shen
- Institute of Molecular Medicine, National Taiwan University, Taipei, Taiwan
| | - Chih-Chang Chou
- Institute of Molecular Medicine, National Taiwan University, Taipei, Taiwan
| | - Ting-Yu Lai
- Institute of Molecular Medicine, National Taiwan University, Taipei, Taiwan
| | - Jer-En Hsu
- Institute of Molecular Medicine, National Taiwan University, Taipei, Taiwan
| | - You-Sheng Lin
- Institute of Molecular Medicine, National Taiwan University, Taipei, Taiwan
| | - Huai-Yu Liu
- Institute of Molecular Medicine, National Taiwan University, Taipei, Taiwan
| | - Yan-Kai Chen
- Institute of Molecular Medicine, National Taiwan University, Taipei, Taiwan
| | - I-Lin Ho
- Institute of Molecular Medicine, National Taiwan University, Taipei, Taiwan
| | - Pang-Hung Hsu
- Department of Bioscience and Biotechnology, National Taiwan Ocean University, Keelung City, Taiwan
| | - Tsung-Hsien Chuang
- Immunology Research Center, National Health Research Institutes, Zhunan, Taiwan
| | - Chih-Yuan Lee
- Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Li-Chung Hsu
- Institute of Molecular Medicine, National Taiwan University, Taipei, Taiwan.,Center of Precision Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
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5
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Crotchett BLM, Ceresa BP. Knockout of c-Cbl slows EGFR endocytic trafficking and enhances EGFR signaling despite incompletely blocking receptor ubiquitylation. Pharmacol Res Perspect 2021; 9:e00756. [PMID: 33811466 PMCID: PMC8019067 DOI: 10.1002/prp2.756] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Accepted: 02/25/2021] [Indexed: 12/17/2022] Open
Abstract
Epidermal growth factor receptor (EGFR) activity is necessary and sufficient for corneal epithelial homeostasis. However, the addition of exogenous Epidermal Growth Factor (EGF) does not reliably restore the corneal epithelium when wounded. This is likely due to high levels of endogenous EGF in tear fluid as well as desensitization of the EGFR following ligand stimulation. We hypothesize that preventing receptor downregulation is an alternative mechanism to enhance EGFR signaling and promote the restoration of compromised corneas. Ligand-dependent EGFR ubiquitylation is associated with the targeted degradation of the receptor. In this manuscript, we determine whether knockout of c-Cbl, an E3 ubiquitin ligase that ubiquitylates the EGFR, is sufficient to prolong EGFR phosphorylation and sustain signaling. Using CRISPR/Cas9 gene editing, we generated immortalized human corneal epithelial (hTCEpi) cells lacking c-Cbl. Knockout (KO) cells expressed the other E3 ligases at the same levels as the control cells, indicating other E3 ligases were not up-regulated. As compared to the control cells, EGF-stimulated EGFR ubiquitylation was reduced in KO cells, but not completely abolished. Similarly, EGF:EGFR trafficking was slowed, with a 35% decrease in the rate of endocytosis and a twofold increase in the receptor half-life. This resulted in a twofold increase in the magnitude of EGFR phosphorylation, with no change in duration. Conversely, Mitogen Activating Protein Kinase (MAPK) phosphorylation did not increase in magnitude but was sustained for 2-3 h as compared to control cells. We propose antagonizing c-Cbl will partially alter receptor ubiquitylation and endocytic trafficking but this is sufficient to enhance downstream signaling.
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Affiliation(s)
- Brandon L M Crotchett
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, USA
| | - Brian P Ceresa
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, USA.,Department of Visual Science, University of Louisville, Louisville, KY, USA
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6
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von Zastrow M, Sorkin A. Mechanisms for Regulating and Organizing Receptor Signaling by Endocytosis. Annu Rev Biochem 2021; 90:709-737. [PMID: 33606955 DOI: 10.1146/annurev-biochem-081820-092427] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Intricate relationships between endocytosis and cellular signaling, first recognized nearly 40 years ago through the study of tyrosine kinase growth factor receptors, are now known to exist for multiple receptor classes and to affect myriad physiological and developmental processes. This review summarizes our present understanding of how endocytosis orchestrates cellular signaling networks, with an emphasis on mechanistic underpinnings and focusing on two receptor classes-tyrosine kinase and G protein-coupled receptors-that have been investigated in particular detail. Together, these examples provide a useful survey of the current consensus, uncertainties, and controversies in this rapidly advancing area of cell biology.
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Affiliation(s)
- Mark von Zastrow
- Department of Psychiatry, University of California, San Francisco, California 94143, USA;
| | - Alexander Sorkin
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261, USA;
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7
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The emerging complexity of PDGFRs: activation, internalization and signal attenuation. Biochem Soc Trans 2021; 48:1167-1176. [PMID: 32369556 DOI: 10.1042/bst20200004] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 04/08/2020] [Accepted: 04/14/2020] [Indexed: 12/30/2022]
Abstract
The platelet-derived growth factor receptor (PDGFR) family of receptor tyrosine kinases allows cells to communicate with the environment to regulate diverse cellular activities. Here, we highlight recent data investigating the structural makeup of individual PDGFRs upon activation, revealing the importance of the whole receptor in the propagation of extracellular ligand binding and dimerization. Furthermore, we review ongoing research demonstrating the significance of receptor internalization and signal attenuation in the regulation of PDGFR activity. Interactions with internalization machinery, signaling from endosomes, receptor degradation and receptor recycling are physiological means by which cells fine-tune PDGFR responses to growth factor stimulation. In this review, we discuss the biophysical, structural, in silico and biochemical data that have provided evidence for these mechanisms. We further highlight the commonalities and differences between PDGFRα and PDGFRβ signaling, revealing critical gaps in knowledge. In total, this review provides a conclusive summary on the state of the PDGFR field and underscores the need for novel techniques to fully elucidate the mechanisms of PDGFR activation, internalization and signal attenuation.
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8
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Eversole D, Subramanian K, Harrison RK, Bourgeois F, Yuksel A, Ben-Yakar A. Femtosecond Plasmonic Laser Nanosurgery (fs-PLN) mediated by molecularly targeted gold nanospheres at ultra-low pulse fluences. Sci Rep 2020; 10:12387. [PMID: 32709944 PMCID: PMC7382507 DOI: 10.1038/s41598-020-68512-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 06/25/2020] [Indexed: 12/16/2022] Open
Abstract
Plasmonic Laser Nanosurgery (PLN) is a novel photomodification technique that exploits the near-field enhancement of femtosecond (fs) laser pulses in the vicinity of gold nanoparticles. While prior studies have shown the advantages of fs-PLN to modify cells, further reduction in the pulse fluence needed to initiate photomodification is crucial to facilitate deep–tissue treatments. This work presents an in-depth study of fs-PLN at ultra-low pulse fluences using 47 nm gold nanoparticles, conjugated to antibodies that target the epithelial growth factor receptor and excited off-resonance using 760 nm, 270 fs laser pulses at 80 MHz repetition rate. We find that fs-PLN can optoporate cellular membranes with pulse fluences as low as 1.3 mJ/cm2, up to two orders of magnitude lower than those used at lower repetition rates. Our results, corroborated by simulations of free-electron generation by particle photoemission and photoionization of the surrounding water, shed light on the off-resonance fs-PLN mechanism. We suggest that photo-chemical pathways likely drive cellular optoporation and cell damage at these off-resonance, low fluence, and high repetition rate fs-laser pulses, with clusters acting as local concentrators of ROS generation. We believe that the low fluence and highly localized ROS-mediated fs-PLN approach will enable targeted therapeutics and cancer treatment.
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Affiliation(s)
- Daniel Eversole
- Biomedical Engineering, The University of Texas At Austin, Austin, TX, 78712, USA
| | - Kaushik Subramanian
- Mechanical Engineering, The University of Texas At Austin, Austin, TX, 78712, USA
| | - Rick K Harrison
- Mechanical Engineering, The University of Texas At Austin, Austin, TX, 78712, USA
| | - Frederic Bourgeois
- Mechanical Engineering, The University of Texas At Austin, Austin, TX, 78712, USA
| | - Anil Yuksel
- Mechanical Engineering, The University of Texas At Austin, Austin, TX, 78712, USA
| | - Adela Ben-Yakar
- Biomedical Engineering, The University of Texas At Austin, Austin, TX, 78712, USA. .,Mechanical Engineering, The University of Texas At Austin, Austin, TX, 78712, USA.
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9
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Chen Y, Huang L, Qi X, Chen C. Insulin Receptor Trafficking: Consequences for Insulin Sensitivity and Diabetes. Int J Mol Sci 2019; 20:ijms20205007. [PMID: 31658625 PMCID: PMC6834171 DOI: 10.3390/ijms20205007] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 10/04/2019] [Accepted: 10/08/2019] [Indexed: 12/12/2022] Open
Abstract
Insulin receptor (INSR) has been extensively studied in the area of cell proliferation and energy metabolism. Impaired INSR activities lead to insulin resistance, the key factor in the pathology of metabolic disorders including type 2 diabetes mellitus (T2DM). The mainstream opinion is that insulin resistance begins at a post-receptor level. The role of INSR activities and trafficking in insulin resistance pathogenesis has been largely ignored. Ligand-activated INSR is internalized and trafficked to early endosome (EE), where INSR is dephosphorylated and sorted. INSR can be subsequently conducted to lysosome for degradation or recycled back to the plasma membrane. The metabolic fate of INSR in cellular events implies the profound influence of INSR on insulin signaling pathways. Disruption of INSR-coupled activities has been identified in a wide range of insulin resistance-related diseases such as T2DM. Accumulating evidence suggests that alterations in INSR trafficking may lead to severe insulin resistance. However, there is very little understanding of how altered INSR activities undermine complex signaling pathways to the development of insulin resistance and T2DM. Here, we focus this review on summarizing previous findings on the molecular pathways of INSR trafficking in normal and diseased states. Through this review, we provide insights into the mechanistic role of INSR intracellular processes and activities in the development of insulin resistance and diabetes.
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Affiliation(s)
- Yang Chen
- School of Biomedical Sciences, The University of Queensland, Brisbane 4072, Australia.
| | - Lili Huang
- School of Biomedical Sciences, The University of Queensland, Brisbane 4072, Australia.
| | - Xinzhou Qi
- School of Biomedical Sciences, The University of Queensland, Brisbane 4072, Australia.
| | - Chen Chen
- School of Biomedical Sciences, The University of Queensland, Brisbane 4072, Australia.
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Crudden C, Song D, Cismas S, Trocmé E, Pasca S, Calin GA, Girnita A, Girnita L. Below the Surface: IGF-1R Therapeutic Targeting and Its Endocytic Journey. Cells 2019; 8:cells8101223. [PMID: 31600876 PMCID: PMC6829878 DOI: 10.3390/cells8101223] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 09/30/2019] [Accepted: 10/03/2019] [Indexed: 12/15/2022] Open
Abstract
Ligand-activated plasma membrane receptors follow pathways of endocytosis through the endosomal sorting apparatus. Receptors cluster in clathrin-coated pits that bud inwards and enter the cell as clathrin-coated vesicles. These vesicles travel through the acidic endosome whereby receptors and ligands are sorted to be either recycled or degraded. The traditional paradigm postulated that the endocytosis role lay in signal termination through the removal of the receptor from the cell surface. It is now becoming clear that the internalization process governs more than receptor signal cessation and instead reigns over the entire spatial and temporal wiring of receptor signaling. Governing the localization, the post-translational modifications, and the scaffolding of receptors and downstream signal components established the endosomal platform as the master regulator of receptor function. Confinement of components within or between distinct organelles means that the endosome instructs the cell on how to interpret and translate the signal emanating from any given receptor complex into biological effects. This review explores this emerging paradigm with respect to the cancer-relevant insulin-like growth factor type 1 receptor (IGF-1R) and discusses how this perspective could inform future targeting strategies.
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Affiliation(s)
- Caitrin Crudden
- Department of Oncology-Pathology, Cellular and Molecular Tumor Pathology, Karolinska Institute, and Karolinska University Hospital, 17164 Stockholm, Sweden.
- Department of Pathology, Cancer Centre Amsterdam, Amsterdam UMC, VU University Medical Centre, 1081 HZ Amsterdam, The Netherlands.
| | - Dawei Song
- Department of Oncology-Pathology, Cellular and Molecular Tumor Pathology, Karolinska Institute, and Karolinska University Hospital, 17164 Stockholm, Sweden.
| | - Sonia Cismas
- Department of Oncology-Pathology, Cellular and Molecular Tumor Pathology, Karolinska Institute, and Karolinska University Hospital, 17164 Stockholm, Sweden.
| | - Eric Trocmé
- Department of Oncology-Pathology, Cellular and Molecular Tumor Pathology, Karolinska Institute, and Karolinska University Hospital, 17164 Stockholm, Sweden.
- St. Erik Eye Hospital, 11282 Stockholm, Sweden.
| | - Sylvya Pasca
- Department of Oncology-Pathology, Cellular and Molecular Tumor Pathology, Karolinska Institute, and Karolinska University Hospital, 17164 Stockholm, Sweden.
| | - George A Calin
- Department of Experimental Therapeutics, The University of Texas, MD Anderson Cancer Center, Houston, TX 77030, USA.
- Center for RNA Interference and Non-Coding RNAs, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
| | - Ada Girnita
- Department of Oncology-Pathology, Cellular and Molecular Tumor Pathology, Karolinska Institute, and Karolinska University Hospital, 17164 Stockholm, Sweden.
- Dermatology Department, Karolinska University Hospital, 17176 Stockholm, Sweden.
| | - Leonard Girnita
- Department of Oncology-Pathology, Cellular and Molecular Tumor Pathology, Karolinska Institute, and Karolinska University Hospital, 17164 Stockholm, Sweden.
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Mathematical modeling of drug-induced receptor internalization in the HER2-positive SKBR3 breast cancer cell-line. Sci Rep 2019; 9:12709. [PMID: 31481718 PMCID: PMC6722142 DOI: 10.1038/s41598-019-49019-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Accepted: 08/19/2019] [Indexed: 12/22/2022] Open
Abstract
About 20% of breast cancer tumors over-express the HER2 receptor. Trastuzumab, an approved drug to treat this type of breast cancer, is a monoclonal antibody directly binding at the HER2 receptor and ultimately inhibiting cancer cell growth. The goal of our study was to understand the early impact of trastuzumab on HER2 internalization and recycling in the HER2-overexpressing breast cancer cell line SKBR3. To this end, fluorescence microscopy, monitoring the amount of HER2 expression in the plasma membrane, was combined with mathematical modeling to derive the flux of HER2 receptors from and to the membrane. We constructed a dynamic multi-compartment model based on ordinary differential equations. To account for cancer cell heterogeneity, a first, dynamic model was expanded to a second model including two distinct cell phenotypes, with implications for different conformational states of HER2, i.e. monomeric or homodimeric. Our mathematical model shows that the hypothesis of fast constitutive HER2 recycling back to the plasma membrane does not match the experimental data. It conclusively describes the experimental observation that trastuzumab induces sustained receptor internalization in cells with membrane ruffles. It is also concluded that for rare, non-ruffled (flat) cells, HER2 internalization occurs three orders of magnitude slower than for the bulk, ruffled cell population.
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12
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Caldieri G, Malabarba MG, Di Fiore PP, Sigismund S. EGFR Trafficking in Physiology and Cancer. PROGRESS IN MOLECULAR AND SUBCELLULAR BIOLOGY 2018; 57:235-272. [PMID: 30097778 DOI: 10.1007/978-3-319-96704-2_9] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Signaling from the epidermal growth factor receptor (EGFR) elicits multiple biological responses, including cell proliferation, migration, and survival. Receptor endocytosis and trafficking are critical physiological processes that control the strength, duration, diversification, and spatial restriction of EGFR signaling through multiple mechanisms, which we review in this chapter. These mechanisms include: (i) regulation of receptor density and activation at the cell surface; (ii) concentration of receptors into distinct nascent endocytic structures; (iii) commitment of the receptor to different endocytic routes; (iv) endosomal sorting and postendocytic trafficking of the receptor through distinct pathways, and (v) recycling to restricted regions of the cell surface. We also highlight how communication between organelles controls EGFR activity along the endocytic route. Finally, we illustrate how abnormal trafficking of EGFR oncogenic mutants, as well as alterations of the endocytic machinery, contributes to aberrant EGFR signaling in cancer.
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Affiliation(s)
- Giusi Caldieri
- Dipartimento di Oncologia ed Emato-oncologia, Università degli Studi di Milano, Via Santa Sofia 9/1, 20122, Milan, Italy
- Istituto Europeo di Oncologia, Via Ripamonti 435, 20141, Milan, Italy
| | - Maria Grazia Malabarba
- Dipartimento di Oncologia ed Emato-oncologia, Università degli Studi di Milano, Via Santa Sofia 9/1, 20122, Milan, Italy
- Istituto Europeo di Oncologia, Via Ripamonti 435, 20141, Milan, Italy
| | - Pier Paolo Di Fiore
- Dipartimento di Oncologia ed Emato-oncologia, Università degli Studi di Milano, Via Santa Sofia 9/1, 20122, Milan, Italy
- Istituto Europeo di Oncologia, Via Ripamonti 435, 20141, Milan, Italy
| | - Sara Sigismund
- Dipartimento di Oncologia ed Emato-oncologia, Università degli Studi di Milano, Via Santa Sofia 9/1, 20122, Milan, Italy.
- Istituto Europeo di Oncologia, Via Ripamonti 435, 20141, Milan, Italy.
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13
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Dykes SS, Steffan JJ, Cardelli JA. Lysosome trafficking is necessary for EGF-driven invasion and is regulated by p38 MAPK and Na+/H+ exchangers. BMC Cancer 2017; 17:672. [PMID: 28978320 PMCID: PMC5628462 DOI: 10.1186/s12885-017-3660-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 09/27/2017] [Indexed: 12/27/2022] Open
Abstract
Background Tumor invasion through a basement membrane is one of the earliest steps in metastasis, and growth factors, such as Epidermal Growth Factor (EGF) and Hepatocyte Growth Factor (HGF), stimulate this process in a majority of solid tumors. Basement membrane breakdown is one of the hallmarks of invasion; therefore, tumor cells secrete a variety of proteases to aid in this process, including lysosomal proteases. Previous studies demonstrated that peripheral lysosome distribution coincides with the release of lysosomal cathepsins. Methods Immunofluorescence microscopy, western blot, and 2D and 3D cell culture techniques were performed to evaluate the effects of EGF on lysosome trafficking and cell motility and invasion. Results EGF-mediated lysosome trafficking, protease secretion, and invasion is regulated by the activity of p38 mitogen activated protein kinase (MAPK) and sodium hydrogen exchangers (NHEs). Interestingly, EGF stimulates anterograde lysosome trafficking through a different mechanism than previously reported for HGF, suggesting that there are redundant signaling pathways that control lysosome positioning and trafficking in tumor cells. Conclusions These data suggest that EGF stimulation induces peripheral (anterograde) lysosome trafficking, which is critical for EGF-mediated invasion and protease release, through the activation of p38 MAPK and NHEs. Taken together, this report demonstrates that anterograde lysosome trafficking is necessary for EGF-mediated tumor invasion and begins to characterize the molecular mechanisms required for EGF-stimulated lysosome trafficking. Electronic supplementary material The online version of this article (10.1186/s12885-017-3660-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Samantha S Dykes
- Department of Microbiology and Immunology, Louisiana State University Health Sciences Center - Shreveport, Shreveport, LA, 71130, USA.,Feist-Weiller Cancer Center, Louisiana State University Health Sciences Center- Shreveport, Shreveport, LA, 71130, USA.,Present Address: Department of Radiation Oncology, University of Florida, Gainesville, FL, 32608, USA
| | - Joshua J Steffan
- Department of Natural Sciences, Dickinson State University, 291 Campus Dr, Dickinson, ND, 58601, USA.
| | - James A Cardelli
- Department of Microbiology and Immunology, Louisiana State University Health Sciences Center - Shreveport, Shreveport, LA, 71130, USA.,Feist-Weiller Cancer Center, Louisiana State University Health Sciences Center- Shreveport, Shreveport, LA, 71130, USA
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14
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Buehler J, Zeltzer S, Reitsma J, Petrucelli A, Umashankar M, Rak M, Zagallo P, Schroeder J, Terhune S, Goodrum F. Opposing Regulation of the EGF Receptor: A Molecular Switch Controlling Cytomegalovirus Latency and Replication. PLoS Pathog 2016; 12:e1005655. [PMID: 27218650 PMCID: PMC4878804 DOI: 10.1371/journal.ppat.1005655] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 05/02/2016] [Indexed: 12/15/2022] Open
Abstract
Herpesviruses persist indefinitely in their host through complex and poorly defined interactions that mediate latent, chronic or productive states of infection. Human cytomegalovirus (CMV or HCMV), a ubiquitous β-herpesvirus, coordinates the expression of two viral genes, UL135 and UL138, which have opposing roles in regulating viral replication. UL135 promotes reactivation from latency and virus replication, in part, by overcoming replication-suppressive effects of UL138. The mechanism by which UL135 and UL138 oppose one another is not known. We identified viral and host proteins interacting with UL138 protein (pUL138) to begin to define the mechanisms by which pUL135 and pUL138 function. We show that pUL135 and pUL138 regulate the viral cycle by targeting that same receptor tyrosine kinase (RTK) epidermal growth factor receptor (EGFR). EGFR is a major homeostatic regulator involved in cellular proliferation, differentiation, and survival, making it an ideal target for viral manipulation during infection. pUL135 promotes internalization and turnover of EGFR from the cell surface, whereas pUL138 preserves surface expression and activation of EGFR. We show that activated EGFR is sequestered within the infection-induced, juxtanuclear viral assembly compartment and is unresponsive to stress. Intriguingly, these findings suggest that CMV insulates active EGFR in the cell and that pUL135 and pUL138 function to fine-tune EGFR levels at the cell surface to allow the infected cell to respond to extracellular cues. Consistent with the role of pUL135 in promoting replication, inhibition of EGFR or the downstream phosphoinositide 3-kinase (PI3K) favors reactivation from latency and replication. We propose a model whereby pUL135 and pUL138 together with EGFR comprise a molecular switch that regulates states of latency and replication in HCMV infection by regulating EGFR trafficking to fine tune EGFR signaling. Cytomegalovirus, a herpesvirus, persists in its host through complex interactions that mediate latent, chronic or productive states of infection. Defining the mechanistic basis viral persistence is important for defining the costs and possible benefits of viral persistence and to mitigate pathologies associated with reactivation. We have identified two genes, UL135 and UL138, with opposing roles in regulating states of latency and replication. UL135 promotes replication and reactivation from latency, in part, by overcoming suppressive effects of UL138. Intriguingly, pUL135 and pUL138 regulate the viral cycle by targeting the same receptor tyrosine kinase, epidermal growth factor receptor (EGFR). EGFR is a major homeostatic regulator controlling cellular proliferation, differentiation, and survival, making it an ideal target for viruses to manipulate during infection. We show that CMV insulates and regulates EGFR levels and activity by modulating its trafficking. This work defines a molecular switch that regulates latent and replicative states of infection through the modulation of host trafficking and signaling pathways. The regulation of EGFR at the cell surface provides a novel means by which the virus may sense and respond to changes in the host environment to enter into or exit the latent state.
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Affiliation(s)
- Jason Buehler
- BIO5 Institute, University of Arizona, Tucson, Arizona, United States of America
| | - Sebastian Zeltzer
- Department of Cellular and Molecular Medicine, University of Arizona, Tucson, Arizona, United States of America
| | - Justin Reitsma
- Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
| | - Alex Petrucelli
- Department of Immunobiology, University of Arizona, Tucson, Arizona, United States of America
| | | | - Mike Rak
- Department of Cellular and Molecular Medicine, University of Arizona, Tucson, Arizona, United States of America
| | - Patricia Zagallo
- Department of Immunobiology, University of Arizona, Tucson, Arizona, United States of America
| | - Joyce Schroeder
- BIO5 Institute, University of Arizona, Tucson, Arizona, United States of America
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, Arizona, United States of America
- University of Arizona Cancer Center, University of Arizona, Tucson, Arizona, United States of America
| | - Scott Terhune
- Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
| | - Felicia Goodrum
- BIO5 Institute, University of Arizona, Tucson, Arizona, United States of America
- Department of Cellular and Molecular Medicine, University of Arizona, Tucson, Arizona, United States of America
- Department of Immunobiology, University of Arizona, Tucson, Arizona, United States of America
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, Arizona, United States of America
- University of Arizona Cancer Center, University of Arizona, Tucson, Arizona, United States of America
- * E-mail:
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15
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Chen MK, Hung MC. Regulation of therapeutic resistance in cancers by receptor tyrosine kinases. Am J Cancer Res 2016; 6:827-842. [PMID: 27186434 PMCID: PMC4859887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 03/06/2016] [Indexed: 06/05/2023] Open
Abstract
In response to DNA damage lesions due to cellular stress, DNA damage response (DDR) pathways are activated to promote cell survival and genetic stability or unrepaired lesion-induced cell death. Current cancer treatments predominantly utilize DNA damaging agents, such as irradiation and chemotherapy drugs, to inhibit cancer cell proliferation and induce cell death through the activation of DDR. However, a portion of cancer patients is reported to develop therapeutic resistance to these DDR-inducing agents. One significant resistance mechanism in cancer cells is oncogenic kinase overexpression, which promotes cell survival by enhancing DNA damage repair pathways and evading cell cycle arrest. Among the oncogenic kinases, overexpression of receptor tyrosine kinases (RTKs) is reported in many of solid tumors, and numerous clinical trials targeting RTKs are currently in progress. As the emerging trend in cancer treatment combines DNA damaging agents and RTK inhibitors, it is important to understand the substrates of RTKs relative to the DDR pathways. In addition, alteration of RTK expression and their phosphorylated substrates can serve as biomarkers to stratify patients for combination therapies. In this review, we summarize the deleterious effects of RTKs on the DDR pathways and the emerging biomarkers for personalized therapy.
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Affiliation(s)
- Mei-Kuang Chen
- Graduate School of Biomedical Science, The University of Texas Health Science Center at HoustonHouston, Texas 77030, USA
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer CenterHouston, Texas, 77030, USA
| | - Mien-Chie Hung
- Graduate School of Biomedical Science, The University of Texas Health Science Center at HoustonHouston, Texas 77030, USA
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer CenterHouston, Texas, 77030, USA
- Center of Molecular Medicine and Graduate Institute of Cancer Biology, China Medical UniversityTaichung 404, Taiwan
- Department of Biotechnology, Asia UniversityTaichung 413, Taiwan
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16
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Endocytosis separates EGF receptors from endogenous fluorescently labeled HRas and diminishes receptor signaling to MAP kinases in endosomes. Proc Natl Acad Sci U S A 2016; 113:2122-7. [PMID: 26858456 DOI: 10.1073/pnas.1520301113] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Signaling from epidermal growth factor receptor (EGFR) to extracellular-stimuli-regulated protein kinase 1/2 (ERK1/2) is proposed to be transduced not only from the cell surface but also from endosomes, although the role of endocytosis in this signaling pathway is controversial. Ras is the only membrane-anchored component in the EGFR-ERK signaling axis, and therefore, its location determines intracellular sites of downstream signaling. Hence, we labeled endogenous H-Ras (HRas) with mVenus fluorescent protein using gene editing in HeLa cells. mVenus-HRas was primarily located at the plasma membrane, and in small amounts in tubular recycling endosomes and associated vesicles. EGF stimulation resulted in fast but transient activation of mVenus-HRas. Although EGF:EGFR complexes were rapidly accumulated in endosomes together with the Grb2 adaptor, very little, if any, mVenus-HRas was detected in these endosomes. Interestingly, the activities of MEK1/2 and ERK1/2 remained high beyond the point of the physical separation of HRas from EGF:EGFR complexes and down-regulation of Ras activity. Paradoxically, this sustained MEK1/2 and ERK1/2 activation was dependent on the active EGFR kinase. Cell surface biotinylation and selective inactivation of surface EGFRs suggested that a small fraction of active EGFRs remaining in the plasma membrane is responsible for continuous signaling to MEK1/2 and ERK1/2. We propose that, under physiological conditions of cell stimulation, EGFR endocytosis serves to spatially separate EGFR-Grb2 complexes and Ras, thus terminating Ras-mediated signaling. However, sustained minimal activation of Ras by a small pool of active EGFRs in the plasma membrane is sufficient for extending MEK1/2 and ERK1/2 activities.
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17
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Smith G, Tomlinson D, Harrison M, Ponnambalam S. Chapter Eight - Ubiquitin-Mediated Regulation of Cellular Responses to Vascular Endothelial Growth Factors. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2016; 141:313-38. [DOI: 10.1016/bs.pmbts.2016.02.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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18
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Chen MK, Hung MC. Proteolytic cleavage, trafficking, and functions of nuclear receptor tyrosine kinases. FEBS J 2015; 282:3693-721. [PMID: 26096795 DOI: 10.1111/febs.13342] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Revised: 05/18/2015] [Accepted: 06/09/2015] [Indexed: 01/18/2023]
Abstract
Intracellular localization has been reported for over three-quarters of receptor tyrosine kinase (RTK) families in response to environmental stimuli. Internalized RTK may bind to non-canonical substrates and affect various cellular processes. Many of the intracellular RTKs exist as fragmented forms that are generated by γ-secretase cleavage of the full-length receptor, shedding, alternative splicing, or alternative translation initiation. Soluble RTK fragments are stabilized and intracellularly transported into subcellular compartments, such as the nucleus, by binding to chaperone or transcription factors, while membrane-bound RTKs (full-length or truncated) are transported from the plasma membrane to the ER through the well-established Rab- or clathrin adaptor protein-coated vesicle retrograde trafficking pathways. Subsequent nuclear transport of membrane-bound RTK may occur via two pathways, INFS or INTERNET, with the former characterized by release of receptors from the ER into the cytosol and the latter characterized by release of membrane-bound receptor from the ER into the nucleoplasm through the inner nuclear membrane. Although most non-canonical intracellular RTK signaling is related to transcriptional regulation, there may be other functions that have yet to be discovered. In this review, we summarize the proteolytic processing, intracellular trafficking and nuclear functions of RTKs, and discuss how they promote cancer progression, and their clinical implications.
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Affiliation(s)
- Mei-Kuang Chen
- The University of Texas Graduate School of Biomedical Sciences at Houston, Houston, TX, USA.,Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Mien-Chie Hung
- The University of Texas Graduate School of Biomedical Sciences at Houston, Houston, TX, USA.,Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.,Center of Molecular Medicine and Graduate Institute of Cancer Biology, China Medical University, Taichung, Taiwan.,Department of Biotechnology, Asia University, Taichung, Taiwan
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19
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Tan X, Sun Y, Thapa N, Liao Y, Hedman AC, Anderson RA. LAPTM4B is a PtdIns(4,5)P2 effector that regulates EGFR signaling, lysosomal sorting, and degradation. EMBO J 2015; 34:475-90. [PMID: 25588945 DOI: 10.15252/embj.201489425] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Lysosomal degradation is essential for the termination of EGF-stimulated EGF receptor (EGFR) signaling. This requires EGFR sorting to the intraluminal vesicles (ILVs) of multi-vesicular endosomes (MVEs). Cytosolic proteins including the ESCRT machineries are key regulators of EGFR intraluminal sorting, but roles for endosomal transmembrane proteins in receptor sorting are poorly defined. Here, we show that LAPTM4B, an endosomal transmembrane oncoprotein, inhibits EGF-induced EGFR intraluminal sorting and lysosomal degradation, leading to enhanced and prolonged EGFR signaling. LAPTM4B blocks EGFR sorting by promoting ubiquitination of Hrs (an ESCRT-0 subunit), which inhibits the Hrs association with ubiquitinated EGFR. This is counteracted by the endosomal PIP kinase, PIPKIγi5, which directly binds LAPTM4B and neutralizes the inhibitory function of LAPTM4B in EGFR sorting by generating PtdIns(4,5)P2 and recruiting SNX5. PtdIns(4,5)P2 and SNX5 function together to protect Hrs from ubiquitination, thereby promoting EGFR intraluminal sorting. These results reveal an essential layer of EGFR trafficking regulated by LAPTM4B, PtdIns(4,5)P2 signaling, and the ESCRT complex and define a mechanism by which the oncoprotein LAPTM4B can transform cells and promote tumor progression.
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Affiliation(s)
- Xiaojun Tan
- Program in Molecular and Cellular Pharmacology, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI, USA
| | - Yue Sun
- Program in Molecular and Cellular Pharmacology, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI, USA
| | - Narendra Thapa
- Program in Molecular and Cellular Pharmacology, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI, USA
| | - Yihan Liao
- Program in Molecular and Cellular Pharmacology, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI, USA
| | - Andrew C Hedman
- Program in Molecular and Cellular Pharmacology, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI, USA
| | - Richard A Anderson
- Program in Molecular and Cellular Pharmacology, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI, USA
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20
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Kornilova ES. Receptor-mediated endocytosis and cytoskeleton. BIOCHEMISTRY (MOSCOW) 2014; 79:865-78. [DOI: 10.1134/s0006297914090041] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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21
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Abstract
Endocytosis is the major regulator of signaling from receptor tyrosine kinases (RTKs). The canonical model of RTK endocytosis involves rapid internalization of an RTK activated by ligand binding at the cell surface and subsequent sorting of internalized ligand-RTK complexes to lysosomes for degradation. Activation of the intrinsic tyrosine kinase activity of RTKs results in autophosphorylation, which is mechanistically coupled to the recruitment of adaptor proteins and conjugation of ubiquitin to RTKs. Ubiquitination serves to mediate interactions of RTKs with sorting machineries both at the cell surface and on endosomes. The pathways and kinetics of RTK endocytic trafficking, molecular mechanisms underlying sorting processes, and examples of deviations from the standard trafficking itinerary in the RTK family are discussed in this work.
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Affiliation(s)
- Lai Kuan Goh
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
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22
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Sun Y, Hedman AC, Tan X, Schill NJ, Anderson RA. Endosomal type Iγ PIP 5-kinase controls EGF receptor lysosomal sorting. Dev Cell 2013; 25:144-55. [PMID: 23602387 DOI: 10.1016/j.devcel.2013.03.010] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2012] [Revised: 01/24/2013] [Accepted: 03/15/2013] [Indexed: 12/24/2022]
Abstract
Endosomal trafficking and degradation of epidermal growth factor receptor (EGFR) play an essential role in the control of its signaling. Phosphatidylinositol-4,5-bisphosphate (PtdIns4,5P(2)) is an established regulator of endocytosis, whereas PtdIns3P modulates endosomal trafficking. However, we demonstrate here that type I gamma phosphatidylinositol phosphate 5-kinase i5 (PIPKIγi5), an enzyme that synthesizes PtdIns4,5P(2), controls endosome-to-lysosome sorting of EGFR. In this pathway, PIPKIγi5 interacts with sorting nexin 5 (SNX5), a protein that binds PtdIns4,5P(2) and other phosphoinositides. PIPKIγi5 and SNX5 localize to endosomes, and loss of either protein blocks EGFR sorting into intraluminal vesicles (ILVs) of the multivesicular body. Loss of ILV sorting greatly enhances and prolongs EGFR signaling. PIPKIγi5 and SNX5 prevent Hrs ubiquitination, and this facilitates the Hrs association with EGFR that is required for ILV sorting. These findings reveal that PIPKIγi5 and SNX5 form a signaling nexus that controls EGFR endosomal sorting, degradation, and signaling.
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Affiliation(s)
- Yue Sun
- University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI 53706, USA
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23
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Li H, Duan ZW, Xie P, Liu YR, Wang WC, Dou SX, Wang PY. Effects of paclitaxel on EGFR endocytic trafficking revealed using quantum dot tracking in single cells. PLoS One 2012; 7:e45465. [PMID: 23029028 PMCID: PMC3447934 DOI: 10.1371/journal.pone.0045465] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2012] [Accepted: 08/22/2012] [Indexed: 12/31/2022] Open
Abstract
Paclitaxel (PTX), a chemotherapeutic drug, affects microtubule dynamics and influences endocytic trafficking. However, the mechanism and the dynamics of altered endocytic trafficking by paclitaxel treatment in single living cells still remain elusive. By labeling quantum dots (QDs) to the epidermal growth factor (EGF), we continuously tracked the endocytosis and post-endocytic trafficking of EGF receptors (EGFRs) in A549 cells for a long time interval. A single-cell analysis method was introduced to quantitatively study the dynamics of endocytic trafficking. Compared with the control cells, the velocity of directed motion was reduced by 30% due to the suppression of high speed movements of EGF-QDs along the microtubules in PTX-treated cells. The endocytic trafficking in PTX-treated cells was mainly via super-diffusive mode of motion, whereas in control cells, it was mostly via sub-diffusive mode of motion. Moreover, PTX shortened endosomal trafficking and prevented EGF-QDs from moving to the perinuclear area via the rapid delivery of EGF-QDs into the peripheral lysosomes. The present study may shed light on the mechanism of the effect of PTX on the treatment of lung cancer.
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Affiliation(s)
- Hui Li
- Key Laboratory of Soft Matter Physics, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China
| | - Zhao-Wen Duan
- Key Laboratory of Soft Matter Physics, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China
| | - Ping Xie
- Key Laboratory of Soft Matter Physics, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China
| | - Yu-Ru Liu
- Key Laboratory of Soft Matter Physics, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China
| | - Wei-Chi Wang
- Key Laboratory of Soft Matter Physics, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China
| | - Shuo-Xing Dou
- Key Laboratory of Soft Matter Physics, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China
| | - Peng-Ye Wang
- Key Laboratory of Soft Matter Physics, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China
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24
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Horowitz A, Seerapu HR. Regulation of VEGF signaling by membrane traffic. Cell Signal 2012; 24:1810-20. [PMID: 22617029 DOI: 10.1016/j.cellsig.2012.05.007] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2012] [Accepted: 05/09/2012] [Indexed: 01/13/2023]
Abstract
Recent findings have drawn attention to the role of membrane traffic in the signaling of vascular endothelial growth factor (VEGF). The significance of this development stems from the pivotal function of VEGF in vasculogenesis and angiogenesis. The outline of the regulation of VEGF receptor (VEGFR) signaling by membrane traffic is similar to that of the epidermal growth factor receptor (EGFR), a prototype of the intertwining between membrane traffic and signaling. There are, however, unique features in VEGFR signaling that are conferred in part by the involvement of the co-receptor neuropilin (Nrp). Nrp1 and VEGFR2 are integrated into membrane traffic through the adaptor protein synectin, which recruits myosin VI, a molecular motor that drives inward trafficking [17,21,64]. The recent detection of only mild vascular defects in a knockin mouse model that expresses Nrp1 lacking a cytoplasmic domain [104], questions the co-receptor's role in VEGF signaling and membrane traffic. The regulation of endocytosis by ephrin-B2 is another feature unique to VEGR2/3 [18,19], but it awaits a mechanistic explanation. Current models do not fully explain how membrane traffic bridges between VEGFR and the downstream effectors that produce its functional outcome, such as cell migration. VEGF-A appears to accomplish this task in part by recruiting endocytic vesicles carrying RhoA to internalized active VEGFR2 [58].
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Affiliation(s)
- Arie Horowitz
- Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic Lerner College of Medicine, 9500 Euclid Avenue, Cleveland, OH 44195, USA.
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25
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Hassink G, Slotman J, Oorschot V, Van Der Reijden BA, Monteferrario D, Noordermeer SM, Van Kerkhof P, Klumperman J, Strous GJ. Identification of the ubiquitin ligase Triad1 as a regulator of endosomal transport. Biol Open 2012; 1:607-14. [PMID: 23213454 PMCID: PMC3509441 DOI: 10.1242/bio.2012778] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
The ubiquitin system plays an important role in trafficking of signaling receptors from the plasma membrane to lysosomes. Triad1 is a ubiquitin ligase that catalyzes the formation of poly-ubiquitin chains linked via lysine-48 as well as lysine-63 residues. We show that depletion of Triad1 affects the sorting of both growth hormone and epidermal growth factor. Triad1-depleted cells accumulate both ligands in endosomes. While fluid phase transport to the lysosomes is reduced in the absence of Triad1, growth hormone receptor can recycle back to the plasma membrane together with transferrin. Using immune electron microscopy we show that Triad1 depletion results in enlarged endosomes with enlarged and irregular shaped intraluminal vesicles. The endosomes display prominent clathrin coats and show increased levels of growth hormone label. We conclude that Triad1 is required for the proper function of multivesicular bodies.
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Affiliation(s)
- Gerco Hassink
- Department of Cell Biology and Institute of Biomembranes, University Medical Center Utrecht , 3584 CX Utrecht , The Netherlands
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26
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Brankatschk B, Wichert SP, Johnson SD, Schaad O, Rossner MJ, Gruenberg J. Regulation of the EGF transcriptional response by endocytic sorting. Sci Signal 2012; 5:ra21. [PMID: 22416276 DOI: 10.1126/scisignal.2002351] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Ligand binding to the epidermal growth factor receptor (EGFR) on the cell surface activates the extracellular signal-regulated kinase (ERK) cascade. Activated, ligand-bound receptors are internalized, and this process may contribute to termination of signaling or enable signaling from intracellular sites. ESCRT (endosomal sorting complex required for transport) complexes may contribute to termination of signaling by sorting receptors into intraluminal vesicles of multivesicular endosomes from which the receptors continue into lysosomes for degradation. We showed that depletion of ESCRTs, which causes the retention of the EGFR in endosomes, increased the activation of the EGFR and its downstream kinases but had little effect on the overall profile and amplitude of the EGF-induced transcriptional response. In contrast, interfering with receptor endocytosis or ubiquitination to keep the EGFR at the cell surface stimulated increases in the abundance of many EGF-induced transcripts, similar to those induced by EGFR overexpression. We also found that the complete EGF transcriptional program was rapidly activated after ligand binding to the receptor. We conclude that the transcriptional response is elicited primarily by receptor molecules at the cell surface.
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Affiliation(s)
- Ben Brankatschk
- Department of Biochemistry, University of Geneva, 30 Quai E. Ansermet, 1211 Geneva 4, Switzerland
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27
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Eden ER, Huang F, Sorkin A, Futter CE. The role of EGF receptor ubiquitination in regulating its intracellular traffic. Traffic 2012; 13:329-37. [PMID: 22017370 PMCID: PMC3261333 DOI: 10.1111/j.1600-0854.2011.01305.x] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2011] [Revised: 10/19/2011] [Accepted: 10/19/2011] [Indexed: 12/21/2022]
Abstract
Progression of activated EGF receptor (EGFR) through the endocytic pathway regulates EGFR signaling. Here we show that a non-ubiquitinated EGFR mutant, unable to bind the endosomal-sorting complex required for transport (ESCRT) component, Hrs, is not efficiently targeted onto intraluminal vesicles (ILVs) of multivesicular endosomes/bodies (MVBs). Moreover, ubiquitination and ESCRT engagement of activated EGFR are required for EGF-stimulated ILV formation. Non-ubiquitinated EGFRs enter clathrin-coated tubules emanating from MVBs and show enhanced recycling to the plasma membrane, compared to wild-type EGFR.
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Affiliation(s)
- Emily R Eden
- UCL Institute of Ophthalmology, University College London, 11-43 Bath Street, London EC1V 9EL, UK
| | - Fangtian Huang
- Department of Cell Biology and Physiology, University of Pittsburgh School of Medicine, 3500 Terrace Street, Pittsburgh, PA 15261 USA
| | - Alexander Sorkin
- Department of Cell Biology and Physiology, University of Pittsburgh School of Medicine, 3500 Terrace Street, Pittsburgh, PA 15261 USA
| | - Clare E Futter
- UCL Institute of Ophthalmology, University College London, 11-43 Bath Street, London EC1V 9EL, UK
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28
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Rosenfeld JL, Knoll BJ, Moore RH. Regulation of G-Protein-Coupled Receptor Activity by Rab GTPases. ACTA ACUST UNITED AC 2011. [DOI: 10.3109/10606820212398] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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29
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Grecco HE, Schmick M, Bastiaens PIH. Signaling from the living plasma membrane. Cell 2011; 144:897-909. [PMID: 21414482 DOI: 10.1016/j.cell.2011.01.029] [Citation(s) in RCA: 183] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2010] [Revised: 12/10/2010] [Accepted: 01/17/2011] [Indexed: 02/06/2023]
Abstract
Our understanding of the plasma membrane, once viewed simply as a static barrier, has been revolutionized to encompass a complex, dynamic organelle that integrates the cell with its extracellular environment. Here, we discuss how bidirectional signaling across the plasma membrane is achieved by striking a delicate balance between restriction and propagation of information over different scales of time and space and how underlying dynamic mechanisms give rise to rich, context-dependent signaling responses. In this Review, we show how computer simulations can generate counterintuitive predictions about the spatial organization of these complex processes.
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Affiliation(s)
- Hernán E Grecco
- Max Planck Institute for Molecular Physiology, Department of Systemic Cell Biology, Otto-Hahn-Str. 11, D-44227 Dortmund, Germany
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30
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β1 integrin controls EGFR signaling and tumorigenic properties of lung cancer cells. Oncogene 2011; 30:4087-96. [DOI: 10.1038/onc.2011.107] [Citation(s) in RCA: 109] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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31
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van Kerkhof P, Westgeest M, Hassink G, Strous GJ. SCFTrCP acts in endosomal sorting of the GH receptor. Exp Cell Res 2011; 317:1071-82. [DOI: 10.1016/j.yexcr.2010.12.020] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2010] [Revised: 12/21/2010] [Accepted: 12/22/2010] [Indexed: 11/26/2022]
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32
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Danglot L, Chaineau M, Dahan M, Gendron MC, Boggetto N, Perez F, Galli T. Role of TI-VAMP and CD82 in EGFR cell-surface dynamics and signaling. J Cell Sci 2010; 123:723-35. [PMID: 20144992 DOI: 10.1242/jcs.062497] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The v-SNARE TI-VAMP (VAMP7) mediates exocytosis during neuritogenesis, phagocytosis and lysosomal secretion. It localizes to endosomes and lysosomes but also to the trans-Golgi network. Here we show that depletion of TI-VAMP enhances the endocytosis of activated EGF receptor (EGFR) without affecting constitutive endocytosis of EGFR, or transferrin uptake. This increased EGFR internalization is mainly clathrin dependent. Searching for defects in EGFR regulators, we found that TI-VAMP depletion reduces the cell surface amount of CD82, a tetraspanin known to control EGFR localization in microdomains. We further show that TI-VAMP is required for secretion from the Golgi apparatus to the cell surface, and that TI-VAMP-positive vesicles transport CD82. Quantum dots video-microscopy indicates that depletion of TI-VAMP, or its cargo CD82, restrains EGFR diffusion and the area explored by EGFR at the cell surface. Both depletions also impair MAPK signaling and enhance endocytosis of activated EGFR by increased recruitment of AP-2. These results highlight the role of TI-VAMP in the secretory pathway of a tetraspanin, and support a model in which CD82 allows EGFR entry in microdomains that control its clathrin-dependent endocytosis and signaling.
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Affiliation(s)
- Lydia Danglot
- INSERM U950, Membrane Traffic in Neuronal & Epithelial Morphogenesis, Paris, F-75013, France
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33
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Gao YS, Hubbert CC, Yao TP. The microtubule-associated histone deacetylase 6 (HDAC6) regulates epidermal growth factor receptor (EGFR) endocytic trafficking and degradation. J Biol Chem 2010; 285:11219-26. [PMID: 20133936 DOI: 10.1074/jbc.m109.042754] [Citation(s) in RCA: 120] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Histone deacetylase 6 (HDAC6) is a microtubule-associated deacetylase with tubulin deacetylase activity, and it binds dynein motors. Recent studies revealed that microtubule acetylation affects the affinity and processivity of microtubule motors. These unique properties implicate a role for HDAC6 in intracellular organelle transport. Here, we show that HDAC6 associates with the endosomal compartments and controls epidermal growth factor receptor (EGFR) trafficking and degradation. We found that loss of HDAC6 promoted EGFR degradation. Mechanistically, HDAC6 deficiency did not cause aberrant EGFR internalization and recycling. Rather, it resulted in accelerated segregation of EGFR from early endosomes and premature delivery of EGFR to the late endosomal and lysosomal compartments. The deregulated EGFR endocytic trafficking was accompanied by an increase in microtubule-dependent movement of EGFR-bearing vesicles, revealing a novel regulation of EGFR vesicular trafficking and degradation by the microtubule deacetylase HDAC6.
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Affiliation(s)
- Ya-sheng Gao
- Department of Pharmacology and Cancer Biology, Duke University, Durham, North Carolina 27710, USA
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Pedersen MW, Jacobsen HJ, Koefoed K, Hey A, Pyke C, Haurum JS, Kragh M. Sym004: a novel synergistic anti-epidermal growth factor receptor antibody mixture with superior anticancer efficacy. Cancer Res 2010; 70:588-97. [PMID: 20068188 DOI: 10.1158/0008-5472.can-09-1417] [Citation(s) in RCA: 171] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Epidermal growth factor receptor (EGFR) is a validated therapeutic target in cancer and EGFR antagonists with greater effectiveness than existing clinical agents remain of interest. Here, we report a novel approach based on Sym004, a mixture of two anti-EGFR monoclonal antibodies directed against distinct nonoverlapping epitopes in EGFR extracellular domain III. Like anti-EGFR monoclonal antibodies in current clinical use, Sym004 inhibits cancer cell growth and survival by blocking ligand-binding receptor activation and phosphorylation and downstream receptor signaling. However, unlike the other antibodies, Sym004 induces rapid and efficient removal of the receptor from the cancer cell surface by triggering EGFR internalization and degradation. Compared with reference anti-EGFR monoclonal antibodies, Sym004 exhibited more pronounced growth inhibition in vitro and superior efficacy in vivo. Together, these findings illustrate a strategy to target EGFR more effectively than existing clinical antibodies.
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35
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Pandey KN. Ligand-mediated endocytosis and intracellular sequestration of guanylyl cyclase/natriuretic peptide receptors: role of GDAY motif. Mol Cell Biochem 2010; 334:81-98. [PMID: 19941037 PMCID: PMC4316816 DOI: 10.1007/s11010-009-0332-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2009] [Accepted: 11/04/2009] [Indexed: 12/31/2022]
Abstract
The guanylyl cyclase/natriuretic peptide receptor-A (GC-A/NPRA), also referred to as GC-A, is a single polypeptide molecule having a critical function in blood pressure regulation and cardiovascular homeostasis. GC-A/NPRA, which resides in the plasma membrane, consists of an extracellular ligand-binding domain, a single transmembrane domain, and an intracellular cytoplasmic region containing a protein kinase-like homology domain (KHD) and a guanylyl cyclase (GC) catalytic domain. After binding with atrial and brain natriuretic peptides (ANP and BNP), GC-A/NPRA is internalized and sequestered into intracellular compartments. Therefore, GC-A/NPRA is a dynamic cellular macromolecule that traverses different subcellular compartments through its lifetime. This review describes the roles of short-signal sequences in the internalization, trafficking, and intracellular redistribution of GC-A/NPRA from cell surface to cell interior. Evidence indicates that, after internalization, the ligand-receptor complexes dissociate inside the cell and a population of GC-A/NPRA recycles back to the plasma membrane. Subsequently, the disassociated ligands are degraded in the lysosomes. However, a small percentage of the ligand escapes the lysosomal degradative pathway, and is released intact into culture medium. Using pharmacologic and molecular perturbants, emphasis has been placed on the cellular regulation and processing of ligand-bound GC-A/NPRA in terms of receptor trafficking and down-regulation in intact cells. The discussion is concluded by examining the functions of short-signal sequence motifs in the cellular life-cycle of GC-A/NPRA, including endocytosis, trafficking, metabolic processing, inactivation, and/or down-regulation in model cell systems.
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Affiliation(s)
- Kailash N Pandey
- Department of Physiology, Tulane University School of Medicine, SL-39 1430 Tulane Ave, New Orleans, LA 70112, USA.
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36
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McGill MA, Dho SE, Weinmaster G, McGlade CJ. Numb regulates post-endocytic trafficking and degradation of Notch1. J Biol Chem 2009; 284:26427-38. [PMID: 19567869 DOI: 10.1074/jbc.m109.014845] [Citation(s) in RCA: 169] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Notch is a transmembrane receptor that controls cell fate decisions during development and tissue homeostasis. Both activation and attenuation of the Notch signal are tightly regulated by endocytosis. The adaptor protein Numb acts as an inhibitor of Notch and is known to function within the intracellular trafficking pathways. However, a role for Numb in regulating Notch trafficking has not been defined. Here we show that mammalian Notch1 is constitutively internalized and trafficked to both recycling and late endosomal compartments, and we demonstrate that changes in Numb expression alter the dynamics of Notch1 trafficking. Overexpression of Numb promotes sorting of Notch1 through late endosomes for degradation, whereas depletion of Numb facilitates Notch1 recycling. Numb mutants that do not interact with the ubiquitin-protein isopeptide ligase, Itch, or that lack motifs important for interaction with endocytic proteins fail to promote Notch1 degradation. Our data suggest that Numb inhibits Notch1 activity by regulating post-endocytic sorting events that lead to Notch1 degradation.
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Affiliation(s)
- Melanie A McGill
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario M5G 1X8, Canada
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37
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Roepstorff K, Grandal MV, Henriksen L, Knudsen SLJ, Lerdrup M, Grøvdal L, Willumsen BM, van Deurs B. Differential effects of EGFR ligands on endocytic sorting of the receptor. Traffic 2009; 10:1115-27. [PMID: 19531065 PMCID: PMC2723868 DOI: 10.1111/j.1600-0854.2009.00943.x] [Citation(s) in RCA: 248] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Endocytic downregulation is a pivotal mechanism turning off signalling from the EGF receptor (EGFR). It is well established that whereas EGF binding leads to lysosomal degradation of EGFR, transforming growth factor (TGF)-α causes receptor recycling. TGF-α therefore leads to continuous signalling and is a more potent mitogen than EGF. In addition to EGF and TGF-α, five EGFR ligands have been identified. Although many of these ligands are upregulated in cancers, very little is known about their effect on EGFR trafficking. We have compared the effect of six different ligands on endocytic trafficking of EGFR. We find that, whereas they all stimulate receptor internalization, they have very diverse effects on endocytic sorting. Heparin-binding EGF-like growth factor and Betacellulin target all EGFRs for lysosomal degradation. In contrast, TGF-α and epiregulin lead to complete receptor recycling. EGF leads to lysosomal degradation of the majority but not all EGFRs. Amphiregulin does not target EGFR for lysosomal degradation but causes fast as well as slow EGFR recycling. The Cbl ubiquitin ligases, especially c-Cbl, are responsible for EGFR ubiquitination after stimulation with all ligands, and persistent EGFR phosphorylation and ubiquitination largely correlate with receptor degradation.
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Affiliation(s)
- Kirstine Roepstorff
- Department of Cellular and Molecular Medicine, The Panum Building, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
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38
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Abstract
This review article describes the pathways and mechanisms of endocytosis and post-endocytic sorting of the EGF receptor (EGFR/ErbB1) and other members of the ErbB family. Growth factor binding to EGFR accelerates its internalization through clathrin-coated pits which is followed by the efficient lysosomal targeting of internalized receptors and results in receptor down-regulation. The role of EGFR interaction with the Grb2 adaptor protein and Cbl ubiquitin ligase, and receptor ubiquitination in the clathrin-dependent internalization and sorting of EGFR in multivesicular endosomes is discussed. Activation and phosphorylation of ErbB2, ErbB3 and ErbB4 also results in their ubiquitination. However, these ErbBs are internalized and targeted to lysosomes less efficiently than EGFR. When overexpressed endocytosis-impaired ErbBs may inhibit the internalization and degradation of EGFR.
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Affiliation(s)
- Alexander Sorkin
- Department of Pharmacology, University of Colorado Denver Anschutz Medical Center, Aurora, Colorado 80045-0508, USA.
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39
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Sigismund S, Argenzio E, Tosoni D, Cavallaro E, Polo S, Di Fiore PP. Clathrin-mediated internalization is essential for sustained EGFR signaling but dispensable for degradation. Dev Cell 2008; 15:209-19. [PMID: 18694561 DOI: 10.1016/j.devcel.2008.06.012] [Citation(s) in RCA: 489] [Impact Index Per Article: 30.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2008] [Revised: 06/11/2008] [Accepted: 06/20/2008] [Indexed: 12/31/2022]
Abstract
Clathrin-mediated endocytosis (CME) is the major pathway of epidermal growth factor receptor (EGFR) internalization. It is commonly believed that CME mediates long-term attenuation of EGFR signaling by targeting the receptor for degradation. However, the EGFR can also be internalized through (a) clathrin-independent pathway(s), and it remains unclear why distinct mechanisms of internalization have evolved. Here, we report that EGFRs internalized via CME are not targeted for degradation, but instead are recycled to the cell surface. By contrast, clathrin-independent internalization preferentially commits the receptor to degradation. This finding has profound implications for signaling, as by skewing EGFR fate toward recycling rather than degradation, CME prolongs the duration of signaling. Our data show that CME determines the longevity of some EGFR-activated signaling pathways and that EGF-dependent biological responses, such as DNA synthesis, absolutely require CME. Thus, CME of the EGFR unexpectedly has a greater impact on receptor signaling than on receptor degradation.
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Affiliation(s)
- Sara Sigismund
- IFOM, Fondazione Istituto FIRC di Oncologia Molecolare, Via Adamello 16, 20139 Milan, Italy
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40
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Endocytosis and intracellular trafficking of ErbBs. Exp Cell Res 2008; 314:3093-106. [PMID: 18793634 DOI: 10.1016/j.yexcr.2008.08.013] [Citation(s) in RCA: 124] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2008] [Revised: 08/18/2008] [Accepted: 08/18/2008] [Indexed: 02/07/2023]
Abstract
This review article describes the pathways and mechanisms of endocytosis and post-endocytic sorting of the EGF receptor (EGFR/ErbB1) and other members of the ErbB family. Growth factor binding to EGFR accelerates its internalization through clathrin-coated pits which is followed by the efficient lysosomal targeting of internalized receptors and results in receptor down-regulation. The role of EGFR interaction with the Grb2 adaptor protein and Cbl ubiquitin ligase, and receptor ubiquitination in the clathrin-dependent internalization and sorting of EGFR in multivesicular endosomes is discussed. Activation and phosphorylation of ErbB2, ErbB3 and ErbB4 also results in their ubiquitination. However, these ErbBs are internalized and targeted to lysosomes less efficiently than EGFR. When overexpressed endocytosis-impaired ErbBs may inhibit the internalization and degradation of EGFR.
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41
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Raiborg C, Malerød L, Pedersen NM, Stenmark H. Differential functions of Hrs and ESCRT proteins in endocytic membrane trafficking. Exp Cell Res 2007; 314:801-13. [PMID: 18031739 DOI: 10.1016/j.yexcr.2007.10.014] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2007] [Revised: 10/17/2007] [Accepted: 10/17/2007] [Indexed: 10/22/2022]
Abstract
A ubiquitin-binding endosomal protein machinery is responsible for sorting endocytosed membrane proteins into intraluminal vesicles of multivesicular endosomes (MVEs) for subsequent degradation in lysosomes. The Hrs-STAM complex and endosomal sorting complex required for transport (ESCRT)-I, -II and -III are central components of this machinery. Here, we have performed a systematic analysis of their importance in four trafficking pathways through endosomes. Neither Hrs, Tsg101 (ESCRT-I), Vps22/EAP30 (ESCRT-II), nor Vps24/CHMP3 (ESCRT-III) was required for ligand-mediated internalization of epidermal growth factor (EGF) receptors (EGFRs) or for recycling of cation-independent mannose 6-phosphate receptors (CI-M6PRs) from endosomes to the trans-Golgi network (TGN). In contrast, both Hrs and ESCRT subunits were equally required for degradation of both endocytosed EGF and EGFR. Whereas depletion of Hrs or Tsg101 caused enhanced recycling of endocytosed EGFRs, this was not the case with depletion of Vps22 or Vps24. Depletion of Vps24 instead caused a strong increase in the levels of CI-M6PRs and a dramatic redistribution of the Golgi and the TGN. These results indicate that, although Hrs-STAM and ESCRT-I, -II and -III have a common function in degradative protein sorting, they play differential roles in other trafficking pathways, probably reflecting their functions at distinct stages of the endocytic pathway.
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Affiliation(s)
- Camilla Raiborg
- Centre for Cancer Biomedicine, University of Oslo, and Department of Biochemistry, the Norwegian Radium Hospital, Rikshospitalet, Norway
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42
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Bakowska JC, Jupille H, Fatheddin P, Puertollano R, Blackstone C. Troyer syndrome protein spartin is mono-ubiquitinated and functions in EGF receptor trafficking. Mol Biol Cell 2007; 18:1683-92. [PMID: 17332501 PMCID: PMC1855030 DOI: 10.1091/mbc.e06-09-0833] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Troyer syndrome is an autosomal recessive hereditary spastic paraplegia caused by mutation in the spartin (SPG20) gene, which encodes a widely expressed protein of unknown function. This mutation results in premature protein truncation and thus might signify a loss-of-function disease mechanism. In this study, we have found that spartin is mono-ubiquitinated and functions in degradation of the epidermal growth factor receptor (EGFR). Upon EGF stimulation, spartin translocates from the cytoplasm to the plasma membrane and colocalizes with internalized EGF-Alexa. Knockdown of spartin by small interfering RNA decreases the rate of EGFR degradation and also affects EGFR internalization, recycling, or both. Furthermore, overexpression of spartin results in a prominent decrease in EGFR degradation. Taken together, our data suggest that spartin is involved in the intracellular trafficking of EGFR and that impaired endocytosis may underlie the pathogenesis of Troyer syndrome.
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Affiliation(s)
- Joanna C. Bakowska
- *Cellular Neurology Unit, National Institute of Neurological Disorders and Stroke, and
| | - Henri Jupille
- *Cellular Neurology Unit, National Institute of Neurological Disorders and Stroke, and
| | - Parvin Fatheddin
- *Cellular Neurology Unit, National Institute of Neurological Disorders and Stroke, and
| | - Rosa Puertollano
- Laboratory of Cell Biology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892
| | - Craig Blackstone
- *Cellular Neurology Unit, National Institute of Neurological Disorders and Stroke, and
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43
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Palmieri D, Bouadis A, Ronchetti R, Merino MJ, Steeg PS. Rab11a differentially modulates epidermal growth factor-induced proliferation and motility in immortal breast cells. Breast Cancer Res Treat 2006; 100:127-37. [PMID: 16791477 DOI: 10.1007/s10549-006-9244-6] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2006] [Accepted: 04/03/2006] [Indexed: 12/25/2022]
Abstract
The development of cancer prevention strategies depends on the elucidation of molecular pathways underlying oncogenesis. In a previous proteomic study of matched normal breast ducts and Ductal Carcinoma in Situ (DCIS), we identified overexpression of Rab11a in DCIS. Rab11a is not well studied in cancer, but is known to regulate the recycling of internalized cell surface proteins and receptors from the early endosome through the trans-Golgi network. Using immunohistochemistry, we confirmed our observation, noting increased Rab11a expression in 19 of 22 (86%) DCIS cases compared to matched normal breast epithelium. To study the function of Rab11a, immortal, nontumorigenic MCF10A breast cells were stimulated with ligands to the EGF receptor (EGFR) after transfection with empty vector (control), Rab11a, or a S25N dominant-negative (DN) Rab11a. Using an iodinated ligand:receptor recycling assay, transfection of Rab11a accelerated, while DN-Rab11a postponed EGFR recycling in vitro. The signaling and in vitro phenotypic consequences of Rab11a expression and function were studied. Transfection of DN-Rab11a increased Erk1/2 activation downstream of EGF, but exerted no effect on the Akt pathway. Expression of DN-Rab11a inhibited MCF10A proliferation by 50-60%, and also inhibited anchorage-dependent colonization. Notably, DN-Rab11a transfection increased motility toward EGFR ligands. The data provide a first demonstration that Rab11a modulates EGFR recycling, and promotes the proliferation but inhibits the motility of an immortal breast line, consistent with the DCIS phenotype.
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Affiliation(s)
- Diane Palmieri
- Women's Cancers Section, Laboratory of Molecular Pharmacology, Laboratory of Pathology, Center for Cancer Research, NCI, NIH, Bethesda, MD 20874, USA.
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44
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Huang F, Kirkpatrick D, Jiang X, Gygi S, Sorkin A. Differential regulation of EGF receptor internalization and degradation by multiubiquitination within the kinase domain. Mol Cell 2006; 21:737-48. [PMID: 16543144 DOI: 10.1016/j.molcel.2006.02.018] [Citation(s) in RCA: 410] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2005] [Revised: 01/23/2006] [Accepted: 02/16/2006] [Indexed: 11/23/2022]
Abstract
Ubiquitination of the EGF receptor (EGFR) is believed to play a critical role in regulating both its localization and its stability. To elucidate the role of EGFR ubiquitination, tandem mass spectrometry was used to identify six distinct lysine residues within the kinase domain of the EGFR, which can be conjugated to ubiquitin following growth factor stimulation. Substitution of these lysine residues with arginines resulted in a dramatic decrease in overall ubiquitination but preserved normal tyrosine phosphorylation of EGFR. Ubiquitination-deficient EGFR mutants displayed a severe defect in their turnover rates but were internalized at rates comparable to those of wild-type receptors. Finally, quantitative mass spectrometry demonstrated that more than 50% of all EGFR bound ubiquitin was in the form of polyubiquitin chains, primarily linked through Lys63. Taken together, these data provide direct evidence for the role of EGFR ubiquitination in receptor targeting to the lysosome and implicate Lys63-linked polyubiquitin chains in this sorting process.
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Affiliation(s)
- Fangtian Huang
- Department of Pharmacology, University of Colorado Health Sciences Center, Aurora, 80045, USA
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45
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Bouley R, Lin HY, Raychowdhury MK, Marshansky V, Brown D, Ausiello DA. Downregulation of the vasopressin type 2 receptor after vasopressin-induced internalization: involvement of a lysosomal degradation pathway. Am J Physiol Cell Physiol 2005; 288:C1390-401. [PMID: 15677378 DOI: 10.1152/ajpcell.00353.2004] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Vasopressin (VP) increases urinary concentration by signaling through the vasopressin receptor (V2R) in collecting duct principal cells. After downregulation, V2R reappears at the cell surface via an unusually slow (several hours) “recycling” pathway. To examine this pathway, we expressed V2R-green fluorescent protein (GFP) in LLC-PK1a cells. V2R-GFP showed characteristics similar to those of wild-type V2R, including high affinity for VP and adenylyl cyclase stimulation. V2R-GFP was located mainly in the plasma membrane in unstimulated cells, but it colocalized with the lysosomal marker Lysotracker after VP-induced internalization. Western blot analysis of V2R-GFP showed a broad 57- to 68-kDa band and a doublet at 46 and 52 kDa before VP treatment. After 4-h VP exposure, the 57- to 68-kDa band lost 50% of its intensity, whereas the lower 46-kDa band increased by 200%. The lysosomal inhibitor chloroquine abolished this VP effect, whereas lactacystin, a proteasome inhibitor, had no effect. Incubating cells at 20°C to block trafficking from the trans-Golgi network reduced V2R membrane fluorescence, and a perinuclear patch developed. Cycloheximide reduced the intensity of this patch, showing that newly synthesized V2R-GFP contributed significantly to its appearance. Cycloheximide also inhibited the reappearance of cell surface V2R after downregulation. We conclude that after downregulation, V2R-GFP is delivered to lysosomes and degraded. Reappearance of V2R at the cell surface depends on new protein synthesis, partially explaining the long time lag needed to fully reestablish V2R at the cell surface after downregulation. This degradative pathway may be an adaptive response to allow receptor-ligand association in the hypertonic and acidic environment of the renal medulla.
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Affiliation(s)
- Richard Bouley
- Program in Membrane Biology and Renal Unit, Department of Medicine, Massachusetts General Hospital East, 149 13th St., Charlestown, MA 02129, USA.
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46
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Pandey KN. Internalization and trafficking of guanylyl cyclase/natriuretic peptide receptor-A. Peptides 2005; 26:985-1000. [PMID: 15911067 DOI: 10.1016/j.peptides.2004.12.020] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2004] [Accepted: 12/20/2004] [Indexed: 10/25/2022]
Abstract
One of the principal loci involved in the regulatory action of atrial and brain natriuretic peptides (ANP and BNP) is guanylyl cyclase/natriuretic peptide receptor-A (GC-A/NPRA), whose ligand-binding efficiency and GC catalytic activity vary remarkably in different target cells and tissues. In its mature form, NPRA resides in the plasma membrane and contains an extracellular ligand-binding domain, a single transmembrane region, and the intracellular protein kinase-like homology domain (KHD) and guanylyl cyclase (GC) catalytic domain. NPRA is a dynamic cellular macromolecule that traverses through different compartments of the cell through its lifetime. Binding of ligand to NPRA triggers a complex array of signal transduction events and accelerates the endocytosis. The endocytic transport is important in regulating signal transduction, formation of specialized signaling complexes, and modulation of specific components of internalization events. The present review describes the experiments which reveal the internalization of ligand-receptor complexes of NPRA, receptor trafficking and recycling, and delivery of both ligand-receptor molecules into subcellular compartments. The ligand-receptor complexes of NPRA are finally degraded within the lysosomes. The experimental evidence provides a consensus forum, which establishes the endocytosis, cellular trafficking, sequestration, and metabolic processing of ANP/NPRA complexes in the intact cells. The discussion is afforded to address the experimental insights into the mechanisms that cells utilize in modulating the delivery and metabolic processing of ligand-bound NPRA into the cell interior.
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Affiliation(s)
- Kailash N Pandey
- Department of Physiology, Tulane University Health Sciences Center and School of Medicine, 1430 Tulane Avenue, New Orleans, LA 70112, USA.
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47
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Hoepfner S, Severin F, Cabezas A, Habermann B, Runge A, Gillooly D, Stenmark H, Zerial M. Modulation of Receptor Recycling and Degradation by the Endosomal Kinesin KIF16B. Cell 2005; 121:437-50. [PMID: 15882625 DOI: 10.1016/j.cell.2005.02.017] [Citation(s) in RCA: 299] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2004] [Revised: 09/27/2004] [Accepted: 02/16/2005] [Indexed: 12/31/2022]
Abstract
Different classes of endosomes exhibit a characteristic intracellular steady-state distribution governed by interactions with the cytoskeleton. We found a kinesin-3, KIF16B, that transports early endosomes to the plus end of microtubules in a process regulated by the small GTPase Rab5 and its effector, the phosphatidylinositol-3-OH kinase hVPS34. In vivo, KIF16B overexpression relocated early endosomes to the cell periphery and inhibited transport to the degradative pathway. Conversely, expression of dominant-negative mutants or ablation of KIF16B by RNAi caused the clustering of early endosomes to the perinuclear region, delayed receptor recycling to the plasma membrane, and accelerated degradation. These results suggest that KIF16B, by regulating the plus end motility of early endosomes, modulates the intracellular localization of early endosomes and the balance between receptor recycling and degradation. We propose that this mechanism could have important implications for signaling.
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Affiliation(s)
- Sebastian Hoepfner
- Max-Planck Institute for Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, D-01307 Dresden, Germany
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48
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Miaczynska M, Pelkmans L, Zerial M. Not just a sink: endosomes in control of signal transduction. Curr Opin Cell Biol 2005; 16:400-6. [PMID: 15261672 DOI: 10.1016/j.ceb.2004.06.005] [Citation(s) in RCA: 374] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Recent studies indicate that endocytic organelles can play a more active role in signal propagation and amplification than was recognised before. By deciphering the interplay between endocytosis and signalling, we will be able to gain a more sophisticated level of understanding of signal transduction mechanisms.
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Affiliation(s)
- Marta Miaczynska
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany.
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Murphy AS, Bandyopadhyay A, Holstein SE, Peer WA. Endocytotic cycling of PM proteins. ANNUAL REVIEW OF PLANT BIOLOGY 2005; 56:221-51. [PMID: 15862095 DOI: 10.1146/annurev.arplant.56.032604.144150] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Plasma membrane protein internalization and recycling mechanisms in plants share many features with other eukaryotic organisms. However, functional and structural differences at the cellular and organismal level mandate specialized mechanisms for uptake, sorting, trafficking, and recycling in plants. Recent evidence of plasma membrane cycling of members of the PIN auxin efflux facilitator family and the KAT1 inwardly rectifying potassium channel demonstrates that endocytotic cycling of some form occurs in plants. However, the mechanisms underlying protein internalization and the signals that stimulate endocytosis of proteins from the cell-environment interface are poorly understood. Here we summarize what is known of endocytotic cycling in animals and compare those mechanisms with what is known in plants. We discuss plant orthologs of mammalian-trafficking proteins involved in endocytotic cycling. The use of the styryl dye FM4-64 to define the course of endocytotic uptake and the fungal toxin brefeldin A to dissect the internalization pathways are particularly emphasized. Additionally, we discuss progress in identifying distinct endosomal populations marked by the small GTPases Ara6 and Ara7 as well as recently described examples of apparent cycling of plasma membrane proteins.
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Affiliation(s)
- Angus S Murphy
- Department of Horticulture, Purdue University, West Lafayette, Indiana 47907, USA.
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Sorkina T, Hoover BR, Zahniser NR, Sorkin A. Constitutive and Protein Kinase C-Induced Internalization of the Dopamine Transporter is Mediated by a Clathrin-Dependent Mechanism. Traffic 2004; 6:157-70. [PMID: 15634215 DOI: 10.1111/j.1600-0854.2005.00259.x] [Citation(s) in RCA: 138] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The amount of dopamine transporter (DAT) present at the cell surface is rapidly regulated by the rates of DAT internalization to endosomes and DAT recycling back to the plasma membrane. The re-distribution of the transporter from the cell surface to endosomes was induced by phorbol ester activation of protein kinase C in porcine aortic endothelial cells stably expressing the human DAT. Inhibition of DAT recycling with the carboxylic ionophore monensin also caused significant accumulation of DAT in early endosomes and a concomitant loss of DAT from the cell surface, due to protein kinase C-independent constitutive internalization of DAT in the absence of recycling. Such monensin-induced relocation of DAT to endosomes was therefore utilized as a measure of the constitutive internalization of DAT. Knock-down of clathrin heavy chain or dynamin II by small interfering RNAs dramatically inhibited both constitutive and protein kinase C-mediated internalization of DAT. In contrast, neither monensin-dependent nor phorbol ester-induced re-distribution of DAT were affected by inhibitors of endocytosis through cholesterol-rich membrane microdomains. Mutational analysis revealed the potential importance of amino acid residues 587-597 in DAT internalization. Altogether, the data suggest that both constitutive and protein kinase C-mediated internalization of DAT utilize the clathrin-dependent endocytic pathway, but likely involve unconventional mechanisms.
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Affiliation(s)
- Tatiana Sorkina
- Department of Pharmacology, University of Colorado Health Sciences Center, Aurora, Colorado 80045, USA
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