1
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Pasquale EB. Eph receptors and ephrins in cancer progression. Nat Rev Cancer 2024; 24:5-27. [PMID: 37996538 PMCID: PMC11015936 DOI: 10.1038/s41568-023-00634-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/03/2023] [Indexed: 11/25/2023]
Abstract
Evidence implicating Eph receptor tyrosine kinases and their ephrin ligands (that together make up the 'Eph system') in cancer development and progression has been accumulating since the discovery of the first Eph receptor approximately 35 years ago. Advances in the past decade and a half have considerably increased the understanding of Eph receptor-ephrin signalling mechanisms in cancer and have uncovered intriguing new roles in cancer progression and drug resistance. This Review focuses mainly on these more recent developments. I provide an update on the different mechanisms of Eph receptor-ephrin-mediated cell-cell communication and cell autonomous signalling, as well as on the interplay of the Eph system with other signalling systems. I further discuss recent advances in elucidating how the Eph system controls tumour expansion, invasiveness and metastasis, supports cancer stem cells, and drives therapy resistance. In addition to functioning within cancer cells, the Eph system also mediates the reciprocal communication between cancer cells and cells of the tumour microenvironment. The involvement of the Eph system in tumour angiogenesis is well established, but recent findings also demonstrate roles in immune cells, cancer-associated fibroblasts and the extracellular matrix. Lastly, I discuss strategies under evaluation for therapeutic targeting of Eph receptors-ephrins in cancer and conclude with an outlook on promising future research directions.
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Affiliation(s)
- Elena B Pasquale
- Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, USA.
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2
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Liang S, Tran E, Du X, Dong J, Sudholz H, Chen H, Qu Z, Huntington ND, Babon JJ, Kershaw NJ, Zhang ZY, Baell JB, Wiede F, Tiganis T. A small molecule inhibitor of PTP1B and PTPN2 enhances T cell anti-tumor immunity. Nat Commun 2023; 14:4524. [PMID: 37500611 PMCID: PMC10374545 DOI: 10.1038/s41467-023-40170-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Accepted: 07/15/2023] [Indexed: 07/29/2023] Open
Abstract
The inhibition of protein tyrosine phosphatases 1B (PTP1B) and N2 (PTPN2) has emerged as an exciting approach for bolstering T cell anti-tumor immunity. ABBV-CLS-484 is a PTP1B/PTPN2 inhibitor in clinical trials for solid tumors. Here we have explored the therapeutic potential of a related small-molecule-inhibitor, Compound-182. We demonstrate that Compound-182 is a highly potent and selective active site competitive inhibitor of PTP1B and PTPN2 that enhances T cell recruitment and activation and represses the growth of tumors in mice, without promoting overt immune-related toxicities. The enhanced anti-tumor immunity in immunogenic tumors can be ascribed to the inhibition of PTP1B/PTPN2 in T cells, whereas in cold tumors, Compound-182 elicited direct effects on both tumor cells and T cells. Importantly, treatment with Compound-182 rendered otherwise resistant tumors sensitive to α-PD-1 therapy. Our findings establish the potential for small molecule inhibitors of PTP1B and PTPN2 to enhance anti-tumor immunity and combat cancer.
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Affiliation(s)
- Shuwei Liang
- Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, 3800, Australia
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, 3800, Australia
| | - Eric Tran
- Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, 3052, Australia
| | - Xin Du
- Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, 3800, Australia
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, 3800, Australia
| | - Jiajun Dong
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, 47907, USA
| | - Harrison Sudholz
- Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, 3800, Australia
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, 3800, Australia
| | - Hao Chen
- Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, 3052, Australia
- Department of Medical Biology, The University of Melbourne, Melbourne, Victoria, 3052, Australia
| | - Zihan Qu
- Department of Chemistry, Purdue University, West Lafayette, IN, 47907, USA
| | - Nicholas D Huntington
- Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, 3800, Australia
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, 3800, Australia
| | - Jeffrey J Babon
- Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, 3052, Australia
- Department of Medical Biology, The University of Melbourne, Melbourne, Victoria, 3052, Australia
| | - Nadia J Kershaw
- Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, 3052, Australia
- Department of Medical Biology, The University of Melbourne, Melbourne, Victoria, 3052, Australia
| | - Zhong-Yin Zhang
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, 47907, USA
- Department of Chemistry, Purdue University, West Lafayette, IN, 47907, USA
| | - Jonathan B Baell
- Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, 3052, Australia
- Lyterian Therapeutics, South San Francisco, San Francisco, CA, 94080, USA
| | - Florian Wiede
- Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, 3800, Australia.
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, 3800, Australia.
| | - Tony Tiganis
- Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, 3800, Australia.
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, 3800, Australia.
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3
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Liang S, Tran E, Du X, Dong J, Sudholz H, Chen H, Qu Z, Huntington N, Babon J, Kershaw N, Zhang ZY, Baell J, Wiede F, Tiganis T. A small molecule inhibitor of PTP1B and PTPN2 enhances T cell anti-tumor immunity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.16.545220. [PMID: 37397992 PMCID: PMC10312756 DOI: 10.1101/2023.06.16.545220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
The inhibition of protein tyrosine phosphatases (PTPs), such as PTP1B and PTPN2 that function as intracellular checkpoints, has emerged as an exciting new approach for bolstering T cell anti-tumor immunity to combat cancer. ABBV-CLS-484 is a dual PTP1B and PTPN2 inhibitor currently in clinical trials for solid tumors. Here we have explored the therapeutic potential of targeting PTP1B and PTPN2 with a related small molecule inhibitor, Compound 182. We demonstrate that Compound 182 is a highly potent and selective active site competitive inhibitor of PTP1B and PTPN2 that enhances antigen-induced T cell activation and expansion ex vivo and represses the growth of syngeneic tumors in C57BL/6 mice without promoting overt immune-related toxicities. Compound 182 repressed the growth of immunogenic MC38 colorectal and AT3-OVA mammary tumors as well as immunologically cold AT3 mammary tumors that are largely devoid of T cells. Treatment with Compound 182 increased both the infiltration and activation of T cells, as well as the recruitment of NK cells and B cells that promote anti-tumor immunity. The enhanced anti-tumor immunity in immunogenic AT3-OVA tumors could be ascribed largely to the inhibition of PTP1B/PTPN2 in T cells, whereas in cold AT3 tumors, Compound 182 elicited both direct effects on tumor cells and T cells to facilitate T cell recruitment and thereon activation. Importantly, treatment with Compound 182 rendered otherwise resistant AT3 tumors sensitive to anti-PD1 therapy. Our findings establish the potential for small molecule active site inhibitors of PTP1B and PTPN2 to enhance anti-tumor immunity and combat cancer.
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4
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Nabavi M, Hiesinger PR. Turnover of synaptic adhesion molecules. Mol Cell Neurosci 2023; 124:103816. [PMID: 36649812 DOI: 10.1016/j.mcn.2023.103816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 12/15/2022] [Accepted: 01/10/2023] [Indexed: 01/15/2023] Open
Abstract
Molecular interactions between pre- and postsynaptic membranes play critical roles during the development, function and maintenance of synapses. Synaptic interactions are mediated by cell surface receptors that may be held in place by trans-synaptic adhesion or intracellular binding to membrane-associated scaffolding and signaling complexes. Despite their role in stabilizing synaptic contacts, synaptic adhesion molecules undergo turnover and degradation during all stages of a neuron's life. Here we review current knowledge about membrane trafficking mechanisms that regulate turnover of synaptic adhesion molecules and the functional significance of turnover for synapse development and function. Based on recent proteomics, genetics and imaging studies, synaptic adhesion molecules exhibit remarkably high turnover rates compared to other synaptic proteins. Degradation occurs predominantly via endolysosomal mechanisms, with little evidence for roles of proteasomal or autophagic degradation. Basal turnover occurs both during synaptic development and maintenance. Neuronal activity typically stabilizes synaptic adhesion molecules while downregulating neurotransmitter receptors based on turnover. In conclusion, constitutive turnover of synaptic adhesion molecules is not a necessarily destabilizing factor, but a basis for the dynamic regulation of trans-synaptic interactions during synapse formation and maintenance.
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Affiliation(s)
- Melinda Nabavi
- Institute for Biology, Division of Neurobiology, Freie Universität Berlin, Germany
| | - P Robin Hiesinger
- Institute for Biology, Division of Neurobiology, Freie Universität Berlin, Germany.
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Identification of Estrogen Signaling in a Prioritization Study of Intraocular Pressure-Associated Genes. Int J Mol Sci 2021; 22:ijms221910288. [PMID: 34638643 PMCID: PMC8508848 DOI: 10.3390/ijms221910288] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 09/20/2021] [Accepted: 09/22/2021] [Indexed: 12/12/2022] Open
Abstract
Elevated intraocular pressure (IOP) is the only modifiable risk factor for primary open-angle glaucoma (POAG). Herein we sought to prioritize a set of previously identified IOP-associated genes using novel and previously published datasets. We identified several genes for future study, including several involved in cytoskeletal/extracellular matrix reorganization, cell adhesion, angiogenesis, and TGF-β signaling. Our differential correlation analysis of IOP-associated genes identified 295 pairs of 201 genes with differential correlation. Pathway analysis identified β-estradiol as the top upstream regulator of these genes with ESR1 mediating 25 interactions. Several genes (i.e., EFEMP1, FOXC1, and SPTBN1) regulated by β-estradiol/ESR1 were highly expressed in non-glaucomatous human trabecular meshwork (TM) or Schlemm’s canal (SC) cells and specifically expressed in TM/SC cell clusters defined by single-cell RNA-sequencing. We confirmed ESR1 gene and protein expression in human TM cells and TM/SC tissue with quantitative real-time PCR and immunofluorescence, respectively. 17β-estradiol was identified in bovine, porcine, and human aqueous humor (AH) using ELISA. In conclusion, we have identified estrogen receptor signaling as a key modulator of several IOP-associated genes. The expression of ESR1 and these IOP-associated genes in TM/SC tissue and the presence of 17β-estradiol in AH supports a role for estrogen signaling in IOP regulation.
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Treps L, Faure S, Clere N. Vasculogenic mimicry, a complex and devious process favoring tumorigenesis – Interest in making it a therapeutic target. Pharmacol Ther 2021; 223:107805. [DOI: 10.1016/j.pharmthera.2021.107805] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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7
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Young KA, Biggins L, Sharpe HJ. Protein tyrosine phosphatases in cell adhesion. Biochem J 2021; 478:1061-1083. [PMID: 33710332 PMCID: PMC7959691 DOI: 10.1042/bcj20200511] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Revised: 02/10/2021] [Accepted: 02/12/2021] [Indexed: 02/07/2023]
Abstract
Adhesive structures between cells and with the surrounding matrix are essential for the development of multicellular organisms. In addition to providing mechanical integrity, they are key signalling centres providing feedback on the extracellular environment to the cell interior, and vice versa. During development, mitosis and repair, cell adhesions must undergo extensive remodelling. Post-translational modifications of proteins within these complexes serve as switches for activity. Tyrosine phosphorylation is an important modification in cell adhesion that is dynamically regulated by the protein tyrosine phosphatases (PTPs) and protein tyrosine kinases. Several PTPs are implicated in the assembly and maintenance of cell adhesions, however, their signalling functions remain poorly defined. The PTPs can act by directly dephosphorylating adhesive complex components or function as scaffolds. In this review, we will focus on human PTPs and discuss their individual roles in major adhesion complexes, as well as Hippo signalling. We have collated PTP interactome and cell adhesome datasets, which reveal extensive connections between PTPs and cell adhesions that are relatively unexplored. Finally, we reflect on the dysregulation of PTPs and cell adhesions in disease.
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Affiliation(s)
- Katherine A. Young
- Signalling Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, U.K
| | - Laura Biggins
- Bioinformatics, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, U.K
| | - Hayley J. Sharpe
- Signalling Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, U.K
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Cruz SA, Qin Z, Ricke KM, Stewart AFR, Chen HH. Neuronal protein-tyrosine phosphatase 1B hinders sensory-motor functional recovery and causes affective disorders in two different focal ischemic stroke models. Neural Regen Res 2021; 16:129-136. [PMID: 32788467 PMCID: PMC7818877 DOI: 10.4103/1673-5374.286970] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Ischemic brain injury causes neuronal death and inflammation. Inflammation activates protein-tyrosine phosphatase 1B (PTP1B). Here, we tested the significance of PTP1B activation in glutamatergic projection neurons on functional recovery in two models of stroke: by photothrombosis, focal ischemic lesions were induced in the sensorimotor cortex (SM stroke) or in the peri-prefrontal cortex (peri-PFC stroke). Elevated PTP1B expression was detected at 4 days and up to 6 weeks after stroke. While ablation of PTP1B in neurons of neuronal knockout (NKO) mice had no effect on the volume or resorption of ischemic lesions, markedly different effects on functional recovery were observed. SM stroke caused severe sensory and motor deficits (adhesive removal test) in wild type and NKO mice at 4 days, but NKO mice showed drastically improved sensory and motor functional recovery at 8 days. In addition, peri-PFC stroke caused anxiety-like behaviors (elevated plus maze and open field tests), and depression-like behaviors (forced swimming and tail suspension tests) in wild type mice 9 and 28 days after stroke, respectively, with minimal effect on sensory and motor function. Peri-PFC stroke-induced affective disorders were associated with fewer active (FosB+) neurons in the PFC and nucleus accumbens but more FosB+ neurons in the basolateral amygdala, compared to sham-operated mice. In contrast, mice with neuronal ablation of PTP1B were protected from anxiety-like and depression-like behaviors and showed no change in FosB+ neurons after peri-PFC stroke. Taken together, our study identifies neuronal PTP1B as a key component that hinders sensory and motor functional recovery and also contributes to the development of anxiety-like and depression-like behaviors after stroke. Thus, PTP1B may represent a novel therapeutic target to improve stroke recovery. All procedures for animal use were approved by the Animal Care and Use Committee of the University of Ottawa Animal Care and Veterinary Service (protocol 1806) on July 27, 2018.
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Affiliation(s)
- Shelly A Cruz
- Ottawa Hospital Research Institute, Neuroscience Program; Brain and Mind Institute, University of Ottawa, Ottawa, ON, Canada
| | - Zhaohong Qin
- Ottawa Hospital Research Institute, Neuroscience Program; Brain and Mind Institute, University of Ottawa, Ottawa, ON, Canada
| | - Konrad M Ricke
- Brain and Mind Institute; Department of Biochemistry, Microbiology and Immunology, University of Ottawa; University of Ottawa Heart Institute, Ottawa, ON, Canada
| | - Alexandre F R Stewart
- Department of Biochemistry, Microbiology and Immunology; Centre for Infection, Immunity and Inflammation, University of Ottawa; University of Ottawa Heart Institute, Ottawa, ON, Canada
| | - Hsiao-Huei Chen
- Ottawa Hospital Research Institute, Neuroscience Program; Brain and Mind Institute; Cellular and Molecular Medicine; Department of Medicine; Centre for Infection, Immunity and Inflammation, University of Ottawa, Ottawa, ON, Canada
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9
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Chen Y, Tang J, Lu T, Liu F. CAPN1 promotes malignant behavior and erlotinib resistance mediated by phosphorylation of c-Met and PIK3R2 via degrading PTPN1 in lung adenocarcinoma. Thorac Cancer 2020; 11:1848-1860. [PMID: 32395869 PMCID: PMC7327690 DOI: 10.1111/1759-7714.13465] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 04/14/2020] [Accepted: 04/17/2020] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND Calpain 1 (CAPN1) has been found to be a promoter of cancer progression. PTPN1 as a physiological target molecule of CAPN1 plays a dephosphorylated role on multiple receptor tyrosine kinases. This study aimed to reveal the effects of CAPN1/PTPN1 on malignant phenotype and EGFR-TKI resistance of lung adenocarcinoma (LUAD) cells. METHODS A total of 84 primary LUAD tissues and paired paracancerous normal tissues were collected. Quantitative real-time PCR (qRT-PCR) and immunohistochemical (IHC) methods were used to measure the expression of CAPN1 and PTPN1 in tissues. qRT-PCR and western blot were used to detect the expressions of CAPN1, PTPN1, c-Met and PIK3R2 in cell lines. Cell counting kit-8 (CCK-8), colony formation and transwell assay were carried out to evaluate cell erlotinib resistance, proliferation, migration and invasion. Co-IP assay was used to verify the interaction between proteins. Cycloheximide (CHX) was applied to block protein synthesis. RESULTS CAPN1, c-Met and PIK3R2 were significantly upregulated and the correlation was positive in LUAD, while PTPN1 was decreased. EGFR-sensitive mutation was related to CAPN1/PTPN1. in vitro studies showed that PTPN1 can mediate dephosphorylation of c-Met and PIK3R2 by binding with both, thereby weakening cell proliferation, metastasis and erlotinib resistance, while CAPN1 could enhance the degradation of PTPN1 protein as a cancer promoter. CONCLUSIONS CAPN1 enhances the malignant behavior and erlotinib resistance of LUAD cells via degrading PTPN1 and then activating c-Met/PIK3R2, which suggests CAPN1/PTPN1 may serve as tumor markers or potential targets for diagnosis and treatment of LUAD. KEY POINTS Significant findings of the study Superior CAPN1 and inferior PTPN1 were related to activation of c-Met/PIK3R2 in lung adenocarcinoma. Moreover, regulations of CAPN1 and PTPN1 induced the changes of malignant behavior and erlotinib resistance. What this study adds Our findings confirmed that CAPN1/PTPN1 play crucial roles on proliferation, metastasis and erlotinib resistance of LUAD cells as c-Met/PIK3R2 regulators, and validated the regulatory mechanism of CAPN1 on PTPN1 in tumor model for the first time.
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Affiliation(s)
- Yichuan Chen
- Department of Cardiovascular Surgery, The Second Xiangya HospitalCentral South UniversityChangshaChina
| | - Jingqun Tang
- Department of Thoracic Surgery, The Second Xiangya HospitalCentral South UniversityChangshaChina
| | - Ting Lu
- Department of Cardiovascular Surgery, The Second Xiangya HospitalCentral South UniversityChangshaChina
| | - Fang Liu
- Clinic Nursing Teaching and Research Section, The Second Xiangya HospitalCentral South UniversityChangshaChina
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10
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Allen CHG, Mervin LH, Mahmoud SY, Bender A. Leveraging heterogeneous data from GHS toxicity annotations, molecular and protein target descriptors and Tox21 assay readouts to predict and rationalise acute toxicity. J Cheminform 2019; 11:36. [PMID: 31152262 PMCID: PMC6544914 DOI: 10.1186/s13321-019-0356-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Accepted: 05/15/2019] [Indexed: 01/06/2023] Open
Abstract
Despite the increasing knowledge in both the chemical and biological domains the assimilation and exploration of heterogeneous datasets, encoding information about the chemical, bioactivity and phenotypic properties of compounds, remains a challenge due to requirement for overlap between chemicals assayed across the spaces. Here, we have constructed a novel dataset, larger than we have used in prior work, comprising 579 acute oral toxic compounds and 1427 non-toxic compounds derived from regulatory GHS information, along with their corresponding molecular and protein target descriptors and qHTS in vitro assay readouts from the Tox21 project. We found no clear association between the results of a FAFDrugs4 toxicophore screen and the acute oral toxicity classifications for our compound set; and a screen using a subset of the ToxAlerts toxicophores was also of limited utility, with only slight enrichment toward the toxic set (odds ratio of 1.48). We then investigated to what degree toxic and non-toxic compounds could be separated in each of the spaces, to compare their potential contribution to further analyses. Using an LDA projection, we found the largest degree of separation using chemical descriptors (Cohen’s d of 1.95) and the lowest degree of separation between toxicity classes using qHTS descriptors (Cohen’s d of 0.67). To compare the predictivity of the feature spaces for the toxicity endpoint, we next trained Random Forest (RF) acute oral toxicity classifiers on either molecular, protein target and qHTS descriptors. RFs trained on molecular and protein target descriptors were most predictive, with ROC AUC values of 0.80–0.92 and 0.70–0.85, respectively, across three test sets. RFs trained on both chemical and protein target descriptors combined exhibited similar predictive performance to the single-domain models (ROC AUC of 0.80–0.91). Model interpretability was improved by the inclusion of protein target descriptors, which allow the identification of specific targets (e.g. Retinal dehydrogenase) with literature links to toxic modes of action (e.g. oxidative stress). The dataset compiled in this study has been made available for future application.
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Affiliation(s)
- Chad H G Allen
- Department of Chemistry, Centre for Molecular Informatics, Lensfield Road, Cambridge, CB2 1EW, UK
| | - Lewis H Mervin
- Department of Chemistry, Centre for Molecular Informatics, Lensfield Road, Cambridge, CB2 1EW, UK
| | - Samar Y Mahmoud
- Department of Chemistry, Centre for Molecular Informatics, Lensfield Road, Cambridge, CB2 1EW, UK
| | - Andreas Bender
- Department of Chemistry, Centre for Molecular Informatics, Lensfield Road, Cambridge, CB2 1EW, UK.
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11
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IRE1α links Nck1 deficiency to attenuated PTP1B expression in HepG2 cells. Cell Signal 2017; 36:79-90. [DOI: 10.1016/j.cellsig.2017.04.017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Revised: 04/11/2017] [Accepted: 04/23/2017] [Indexed: 12/23/2022]
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12
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Willoughby LF, Manent J, Allan K, Lee H, Portela M, Wiede F, Warr C, Meng TC, Tiganis T, Richardson HE. Differential regulation of protein tyrosine kinase signalling by Dock and the PTP61F variants. FEBS J 2017; 284:2231-2250. [PMID: 28544778 DOI: 10.1111/febs.14118] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 04/12/2017] [Accepted: 05/19/2017] [Indexed: 01/01/2023]
Abstract
Tyrosine phosphorylation-dependent signalling is coordinated by the opposing actions of protein tyrosine kinases (PTKs) and protein tyrosine phosphatases (PTPs). There is a growing list of adaptor proteins that interact with PTPs and facilitate the dephosphorylation of substrates. The extent to which any given adaptor confers selectivity for any given substrate in vivo remains unclear. Here we have taken advantage of Drosophila melanogaster as a model organism to explore the influence of the SH3/SH2 adaptor protein Dock on the abilities of the membrane (PTP61Fm)- and nuclear (PTP61Fn)-targeted variants of PTP61F (the Drosophila othologue of the mammalian enzymes PTP1B and TCPTP respectively) to repress PTK signalling pathways in vivo. PTP61Fn effectively repressed the eye overgrowth associated with activation of the epidermal growth factor receptor (EGFR), PTK, or the expression of the platelet-derived growth factor/vascular endothelial growth factor receptor (PVR) or insulin receptor (InR) PTKs. PTP61Fn repressed EGFR and PVR-induced mitogen-activated protein kinase signalling and attenuated PVR-induced STAT92E signalling. By contrast, PTP61Fm effectively repressed EGFR- and PVR-, but not InR-induced tissue overgrowth. Importantly, coexpression of Dock with PTP61F allowed for the efficient repression of the InR-induced eye overgrowth, but did not enhance the PTP61Fm-mediated inhibition of EGFR and PVR-induced signalling. Instead, Dock expression increased, and PTP61Fm coexpression further exacerbated the PVR-induced eye overgrowth. These results demonstrate that Dock selectively enhances the PTP61Fm-mediated attenuation of InR signalling and underscores the specificity of PTPs and the importance of adaptor proteins in regulating PTP function in vivo.
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Affiliation(s)
| | - Jan Manent
- Department of Biochemistry & Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria, Australia
| | - Kirsten Allan
- Department of Biochemistry & Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria, Australia
| | - Han Lee
- Institute of Biochemical Sciences, National Taiwan University, and Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
| | - Marta Portela
- Department of Biochemistry & Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria, Australia
| | - Florian Wiede
- Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia.,Department of Biochemistry & Molecular Biology, Biomedicine Discovery Institute, Monash University, Melbourne, Victoria, Australia
| | - Coral Warr
- School of Biomedical Sciences, Monash University, Clayton, Victoria, Australia
| | - Tzu-Ching Meng
- Institute of Biochemical Sciences, National Taiwan University, and Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
| | - Tony Tiganis
- Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia.,Department of Biochemistry & Molecular Biology, Biomedicine Discovery Institute, Monash University, Melbourne, Victoria, Australia
| | - Helena E Richardson
- Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia.,Department of Biochemistry & Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria, Australia.,Peter MacCallum Department of Oncology, University of Melbourne, Victoria, Australia.,Department of Biochemistry & Molecular Biology, University of Melbourne, Victoria, Australia.,Department of Anatomy & Neuroscience, University of Melbourne, Victoria, Australia
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13
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Abstract
Phosphatases play key roles in normal physiology and diseases. Studying phosphatases has been both essential and challenging, and the application of conventional genetic and biochemical methods has led to crucial but still limited understanding of their mechanisms, substrates, and exclusive functions within highly intricate networks. With the advances in technologies such as cellular imaging and molecular and chemical biology in terms of sensitive tools and methods, the phosphatase field has thrived in the past years and has set new insights for cell signaling studies and for therapeutic development. In this review, we give an overview of the existing interdisciplinary tools for phosphatases, give examples on how they have been applied to increase our understanding of these enzymes, and suggest how they-and other tools yet barely used in the phosphatase field-might be adapted to address future questions and challenges.
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Affiliation(s)
- Sara Fahs
- European Molecular Biology Laboratory, Genome Biology
Unit, Meyerhofstrasse
1, 69117 Heidelberg, Germany
| | - Pablo Lujan
- European Molecular Biology Laboratory, Genome Biology
Unit, Meyerhofstrasse
1, 69117 Heidelberg, Germany
| | - Maja Köhn
- European Molecular Biology Laboratory, Genome Biology
Unit, Meyerhofstrasse
1, 69117 Heidelberg, Germany
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14
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Gong J, Körner R, Gaitanos L, Klein R. Exosomes mediate cell contact-independent ephrin-Eph signaling during axon guidance. J Cell Biol 2016; 214:35-44. [PMID: 27354374 PMCID: PMC4932373 DOI: 10.1083/jcb.201601085] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 06/07/2016] [Indexed: 11/24/2022] Open
Abstract
Ephs interact with ESCRT complex components and are released via extracellular vesicles or exosomes. EphB2 released via exosomes mediates a novel cell contact–independent mode of ephrin-Eph signaling that contributes to axon guidance in cell–cell repulsion processes. The cellular release of membranous vesicles known as extracellular vesicles (EVs) or exosomes represents a novel mode of intercellular communication. Eph receptor tyrosine kinases and their membrane-tethered ephrin ligands have very important roles in such biologically diverse processes as neuronal development, plasticity, and pathological diseases. Until now, it was thought that ephrin-Eph signaling requires direct cell contact. Although the biological functions of ephrin-Eph signaling are well understood, our mechanistic understanding remains modest. Here we report the release of EVs containing Ephs and ephrins by different cell types, a process requiring endosomal sorting complex required for transport (ESCRT) activity and regulated by neuronal activity. Treatment of cells with purified EphB2+ EVs induces ephrinB1 reverse signaling and causes neuronal axon repulsion. These results indicate a novel mechanism of ephrin-Eph signaling independent of direct cell contact and proteolytic cleavage and suggest the participation of EphB2+ EVs in neural development and synapse physiology.
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Affiliation(s)
- Jingyi Gong
- Max Planck Institute of Neurobiology, 82152 Martinsried, Germany Munich Cluster for Systems Neurology (SyNergy), 80336 Munich, Germany
| | - Roman Körner
- Max Planck Institute of Biochemistry, 82152 Martinsried, Germany Munich Cluster for Systems Neurology (SyNergy), 80336 Munich, Germany
| | - Louise Gaitanos
- Max Planck Institute of Neurobiology, 82152 Martinsried, Germany
| | - Rüdiger Klein
- Max Planck Institute of Neurobiology, 82152 Martinsried, Germany Munich Cluster for Systems Neurology (SyNergy), 80336 Munich, Germany
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15
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González Wusener AE, González Á, Nakamura F, Arregui CO. PTP1B triggers integrin-mediated repression of myosin activity and modulates cell contractility. Biol Open 2015; 5:32-44. [PMID: 26700725 PMCID: PMC4728310 DOI: 10.1242/bio.015883] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Cell contractility and migration by integrins depends on precise regulation of protein tyrosine kinase and Rho-family GTPase activities in specific spatiotemporal patterns. Here we show that protein tyrosine phosphatase PTP1B cooperates with β3 integrin to activate the Src/FAK signalling pathway which represses RhoA-myosin-dependent contractility. Using PTP1B null (KO) cells and PTP1B reconstituted (WT) cells, we determined that some early steps following cell adhesion to fibronectin and vitronectin occurred robustly in WT cells, including aggregation of β3 integrins and adaptor proteins, and activation of Src/FAK-dependent signalling at small puncta in a lamellipodium. However, these events were significantly impaired in KO cells. We established that cytoskeletal strain and cell contractility was highly enhanced at the periphery of KO cells compared to WT cells. Inhibition of the Src/FAK signalling pathway or expression of constitutive active RhoA in WT cells induced a KO cell phenotype. Conversely, expression of constitutive active Src or myosin inhibition in KO cells restored the WT phenotype. We propose that this novel function of PTP1B stimulates permissive conditions for adhesion and lamellipodium assembly at the protruding edge during cell spreading and migration. Summary: Here we show that protein tyrosine phosphatase PTP1B cooperates with β3 integrin to transiently repress RhoA-myosin-dependent contractility, stimulating adhesion and lamellipodium assembly during cell spreading and migration.
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Affiliation(s)
- Ana E González Wusener
- IIB-INTECH, Universidad Nacional de San Martín, 1650 San Martín, Buenos Aires, Argentina
| | - Ángela González
- IIB-INTECH, Universidad Nacional de San Martín, 1650 San Martín, Buenos Aires, Argentina
| | - Fumihiko Nakamura
- Hematology Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02445, USA
| | - Carlos O Arregui
- IIB-INTECH, Universidad Nacional de San Martín, 1650 San Martín, Buenos Aires, Argentina
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16
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Ubiquitination switches EphA2 vesicular traffic from a continuous safeguard to a finite signalling mode. Nat Commun 2015; 6:8047. [PMID: 26292967 PMCID: PMC4560775 DOI: 10.1038/ncomms9047] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Accepted: 07/11/2015] [Indexed: 01/15/2023] Open
Abstract
Autocatalytic phosphorylation of receptor tyrosine kinases (RTKs) enables diverse, context-dependent responses to extracellular signals but comes at the price of autonomous, ligand-independent activation. Using a conformational biosensor that reports on the kinase activity of the cell guidance ephrin receptor type-A (EphA2) in living cells, we observe that autonomous EphA2 activation is suppressed by vesicular recycling and dephosphorylation by protein tyrosine phosphatases 1B (PTP1B) near the pericentriolar recycling endosome. This spatial segregation of catalytically superior PTPs from RTKs at the plasma membrane is essential to preserve ligand responsiveness. Ligand-induced clustering, on the other hand, promotes phosphorylation of a c-Cbl docking site and ubiquitination of the receptor, thereby redirecting it to the late endosome/lysosome. We show that this switch from cyclic to unidirectional receptor trafficking converts a continuous suppressive safeguard mechanism into a transient ligand-responsive signalling mode.
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17
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Abstract
Epithelial cells are tightly coupled together through specialized intercellular junctions, including adherens junctions, desmosomes, tight junctions, and gap junctions. A growing body of evidence suggests epithelial cells also directly exchange information at cell-cell contacts via the Eph family of receptor tyrosine kinases and their membrane-associated ephrin ligands. Ligand-dependent and -independent signaling via Eph receptors as well as reverse signaling through ephrins impact epithelial tissue homeostasis by organizing stem cell compartments and regulating cell proliferation, migration, adhesion, differentiation, and survival. This review focuses on breast, gut, and skin epithelia as representative examples for how Eph receptors and ephrins modulate diverse epithelial cell responses in a context-dependent manner. Abnormal Eph receptor and ephrin signaling is implicated in a variety of epithelial diseases raising the intriguing possibility that this cell-cell communication pathway can be therapeutically harnessed to normalize epithelial function in pathological settings like cancer or chronic inflammation.
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Key Words
- ADAM, a disintegrin and metalloprotease
- Apc, adenomatous polyposis coli
- Breast
- ER, estrogen receptor
- Eph receptor
- Eph, erythropoietin-producing hepatocellular
- Erk, extracellular signal-regulated kinase
- GEF, guanine nucleotide exchange factor
- GPI, glycosylphosphatidylinositol
- HER2, human epidermal growth factor receptor 2
- HGF, hepatocyte growth factor
- IBD, inflammatory bowel disease
- KLF, Krüppel-like factor
- MAPK, mitogen-activated protein kinase
- MMTV-LTR, mouse mammary tumor virus-long terminal repeat
- MT1-MMP, membrane-type 1 matrix metalloproteinase
- PDZ, postsynaptic density protein 95, discs large 1, and zonula occludens-1
- PTP, protein tyrosine phosphatase
- RTK, receptor tyrosine kinase
- SH2, Src homology 2
- SHIP2, SH2 inositol phosphatase 2
- SLAP, Src-like adaptor protein
- TCF, T-cell specific transcription factor
- TEB, terminal end bud
- TNFα, tumor necrosis factor α.
- cell-cell
- ephrin
- epithelial
- intestine
- receptor tyrosine kinase
- skin
- stem cell
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18
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Aharon R, Janes PW, Burgess AW, Hamza K, Klebaner F, Lackmann M. A mathematical model for eph/ephrin-directed segregation of intermingled cells. PLoS One 2014; 9:e111803. [PMID: 25436892 PMCID: PMC4249859 DOI: 10.1371/journal.pone.0111803] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Accepted: 10/04/2014] [Indexed: 11/19/2022] Open
Abstract
Eph receptors, the largest family of receptor tyrosine kinases, control cell-cell adhesion/de-adhesion, cell morphology and cell positioning through interaction with cell surface ephrin ligands. Bi-directional signalling from the Eph and ephrin complexes on interacting cells have a significant role in controlling normal tissue development and oncogenic tissue patterning. Eph-mediated tissue patterning is based on the fine-tuned balance of adhesion and de-adhesion reactions between distinct Eph- and ephrin-expressing cell populations, and adhesion within like populations (expressing either Eph or ephrin). Here we develop a stochastic, Lagrangian model that is based on Eph/ephrin biology: incorporating independent Brownian motion to describe cell movement and a deterministic term (the drift term) to represent repulsive and adhesive interactions between neighbouring cells. Comparison between the experimental and computer simulated Eph/ephrin cell patterning events shows that the model recapitulates the dynamics of cell-cell segregation and cell cluster formation. Moreover, by modulating the term for Eph/ephrin-mediated repulsion, the model can be tuned to match the actual behaviour of cells with different levels of Eph expression or activity. Together the results of our experiments and modelling suggest that the complexity of Eph/ephrin signalling mechanisms that control cell-cell interactions can be described well by a mathematical model with a single term balancing adhesion and de-adhesion between interacting cells. This model allows reliable prediction of Eph/ephrin-dependent control of cell patterning behaviour.
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Affiliation(s)
- Rotem Aharon
- School of Mathematical Sciences, Monash University, Clayton, Victoria, Australia
- * E-mail: (RA); (PWJ)
| | - Peter W. Janes
- Department of Biochemistry & Molecular Biology, Monash University, Clayton, Victoria, Australia
- * E-mail: (RA); (PWJ)
| | - Anthony W. Burgess
- Structural Biology Division, The Walter and Eliza Hall Institute, Parkville, Victoria, Australia
| | - Kais Hamza
- School of Mathematical Sciences, Monash University, Clayton, Victoria, Australia
| | - Fima Klebaner
- School of Mathematical Sciences, Monash University, Clayton, Victoria, Australia
| | - Martin Lackmann
- Department of Biochemistry & Molecular Biology, Monash University, Clayton, Victoria, Australia
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Scott AM, Tiganis T. Pioneer of Eph biology and therapeutics: Martin Lackmann (1956-2014). Growth Factors 2014; 32:171-3. [PMID: 25401411 DOI: 10.3109/08977194.2014.983226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Andrew M Scott
- Ludwig Institute for Cancer Research , Melbourne, VIC , Australia
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20
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Abstract
Eph receptor tyrosine kinases control cell-cell interactions during normal and oncogenic development, and are implicated in a range of processes including angiogenesis, stem cell maintenance and metastasis. They are thus of great interest as targets for cancer therapy. EphA3, originally isolated from leukemic and melanoma cells, is presently one of the most promising therapeutic targets, with multiple tumor-promoting roles in a variety of cancer types. This review focuses on EphA3, its functions in controlling cellular behavior, both in normal and pathological development, and most particularly in cancer.
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Affiliation(s)
- Peter W Janes
- Department of Biochemistry and Molecular Biology, Monash University , Victoria , Australia and
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21
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Apical localization of inositol 1,4,5-trisphosphate receptors is independent of extended synaptotagmins in hepatocytes. PLoS One 2014; 9:e114043. [PMID: 25437447 PMCID: PMC4250053 DOI: 10.1371/journal.pone.0114043] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Accepted: 11/03/2014] [Indexed: 12/12/2022] Open
Abstract
Extended synaptotagmins (E-Syts) are a recently identified family of proteins that tether the endoplasmic reticulum (ER) to the plasma membrane (PM) in part by conferring regulation of cytosolic calcium (Ca2+) at these contact sites (Cell, 2013). However, the mechanism by which E-Syts link this tethering to Ca2+ signaling is unknown. Ca2+ waves in polarized epithelia are initiated by inositol 1,4,5-trisphosphate receptors (InsP3Rs), and these waves begin in the apical region because InsP3Rs are targeted to the ER adjacent to the apical membrane. In this study we investigated whether E-Syts are responsible for this targeting. Primary rat hepatocytes were used as a model system, because a single InsP3R isoform (InsP3R-II) is tethered to the peri-apical ER in these cells. Additionally, it has been established in hepatocytes that the apical localization of InsP3Rs is responsible for Ca2+ waves and secretion and is disrupted in disease states in which secretion is impaired. We found that rat hepatocytes express two of the three identified E-Syts (E-Syt1 and E-Syt2). Individual or simultaneous siRNA knockdown of these proteins did not alter InsP3R-II expression levels, apical localization or average InsP3R-II cluster size. Moreover, apical secretion of the organic anion 5-chloromethylfluorescein diacetate (CMFDA) was not changed in cells lacking E-Syts but was reduced in cells in which cytosolic Ca2+ was buffered. These data provide evidence that E-Syts do not participate in the targeting of InsP3Rs to the apical region. Identifying tethers that bring InsP3Rs to the apical region remains an important question, since mis-targeting of InsP3Rs leads to impaired secretory activity.
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22
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To C, Farnsworth RH, Vail ME, Chheang C, Gargett CE, Murone C, Llerena C, Major AT, Scott AM, Janes PW, Lackmann M. Hypoxia-controlled EphA3 marks a human endometrium-derived multipotent mesenchymal stromal cell that supports vascular growth. PLoS One 2014; 9:e112106. [PMID: 25420155 PMCID: PMC4242616 DOI: 10.1371/journal.pone.0112106] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Accepted: 10/13/2014] [Indexed: 12/21/2022] Open
Abstract
Eph and ephrin proteins are essential cell guidance cues that orchestrate cell navigation and control cell-cell interactions during developmental tissue patterning, organogenesis and vasculogenesis. They have been extensively studied in animal models of embryogenesis and adult tissue regeneration, but less is known about their expression and function during human tissue and organ regeneration. We discovered the hypoxia inducible factor (HIF)-1α-controlled expression of EphA3, an Eph family member with critical functions during human tumour progression, in the vascularised tissue of regenerating human endometrium and on isolated human endometrial multipotent mesenchymal stromal cells (eMSCs), but not in other highly vascularised human organs. EphA3 affinity-isolation from human biopsy tissue yielded multipotent CD29+/CD73+/CD90+/CD146+ eMSCs that can be clonally propagated and respond to EphA3 agonists with EphA3 phosphorylation, cell contraction, cell-cell segregation and directed cell migration. EphA3 silencing significantly inhibited the ability of transplanted eMSCs to support neovascularisation in immunocompromised mice. In accord with established roles of Eph receptors in mediating interactions between endothelial and perivascular stromal cells during mouse development, our findings suggest that HIF-1α-controlled expression of EphA3 on human MSCs functions during the hypoxia-initiated early stages of adult blood vessel formation.
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MESH Headings
- Adult
- Animals
- Blotting, Western
- Cell Hypoxia
- Cells, Cultured
- Endometrium/cytology
- Female
- Gene Expression
- Heterografts/blood supply
- Humans
- Hypoxia-Inducible Factor 1, alpha Subunit/genetics
- Hypoxia-Inducible Factor 1, alpha Subunit/metabolism
- Male
- Mesenchymal Stem Cell Transplantation/methods
- Mesenchymal Stem Cells/metabolism
- Mice, Inbred BALB C
- Mice, Nude
- Microscopy, Fluorescence
- Multipotent Stem Cells/metabolism
- Multipotent Stem Cells/transplantation
- Neovascularization, Physiologic
- RNA Interference
- Receptor, EphA3/genetics
- Receptor, EphA3/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Transplantation, Heterologous
- Young Adult
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Affiliation(s)
- Catherine To
- Department of Biochemistry & Molecular Biology, Monash University, Melbourne, Victoria, Australia
| | - Rae H. Farnsworth
- Department of Biochemistry & Molecular Biology, Monash University, Melbourne, Victoria, Australia
- * E-mail:
| | - Mary E. Vail
- Department of Biochemistry & Molecular Biology, Monash University, Melbourne, Victoria, Australia
| | - Chanly Chheang
- Department of Biochemistry & Molecular Biology, Monash University, Melbourne, Victoria, Australia
| | | | - Carmel Murone
- Ludwig Institute for Cancer Research, Olivia Newton-John Cancer & Wellness Centre, Melbourne, Victoria, Australia
| | - Carmen Llerena
- Department of Biochemistry & Molecular Biology, Monash University, Melbourne, Victoria, Australia
| | - Andrew T. Major
- Department of Anatomy & Developmental Biology, Monash University, Melbourne, Victoria, Australia
| | - Andrew M. Scott
- Ludwig Institute for Cancer Research, Olivia Newton-John Cancer & Wellness Centre, Melbourne, Victoria, Australia
| | - Peter W. Janes
- Department of Biochemistry & Molecular Biology, Monash University, Melbourne, Victoria, Australia
| | - Martin Lackmann
- Department of Biochemistry & Molecular Biology, Monash University, Melbourne, Victoria, Australia
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23
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Gucciardo E, Sugiyama N, Lehti K. Eph- and ephrin-dependent mechanisms in tumor and stem cell dynamics. Cell Mol Life Sci 2014; 71:3685-710. [PMID: 24794629 PMCID: PMC11113620 DOI: 10.1007/s00018-014-1633-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2013] [Revised: 03/31/2014] [Accepted: 04/17/2014] [Indexed: 01/17/2023]
Abstract
The erythropoietin-producing hepatocellular (Eph) receptors comprise the largest family of receptor tyrosine kinases (RTKs). Initially regarded as axon-guidance and tissue-patterning molecules, Eph receptors have now been attributed with various functions during development, tissue homeostasis, and disease pathogenesis. Their ligands, ephrins, are synthesized as membrane-associated molecules. At least two properties make this signaling system unique: (1) the signal can be simultaneously transduced in the receptor- and the ligand-expressing cell, (2) the signaling outcome through the same molecules can be opposite depending on cellular context. Moreover, shedding of Eph and ephrin ectodomains as well as ligand-dependent and -independent receptor crosstalk with other RTKs, proteases, and adhesion molecules broadens the repertoire of Eph/ephrin functions. These integrated pathways provide plasticity to cell-microenvironment communication in varying tissue contexts. The complex molecular networks and dynamic cellular outcomes connected to the Eph/ephrin signaling in tumor-host communication and stem cell niche are the main focus of this review.
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Affiliation(s)
- Erika Gucciardo
- Research Programs Unit, Genome-Scale Biology, Biomedicum Helsinki, University of Helsinki, P.O.B. 63, 00014 Helsinki, Finland
| | - Nami Sugiyama
- Research Programs Unit, Genome-Scale Biology, Biomedicum Helsinki, University of Helsinki, P.O.B. 63, 00014 Helsinki, Finland
- Department of Biosystems Science and Bioengineering, ETH Zurich, Mattenstrasse 26, 4058 Basel, Switzerland
| | - Kaisa Lehti
- Research Programs Unit, Genome-Scale Biology, Biomedicum Helsinki, University of Helsinki, P.O.B. 63, 00014 Helsinki, Finland
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24
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Bakke J, Haj FG. Protein-tyrosine phosphatase 1B substrates and metabolic regulation. Semin Cell Dev Biol 2014; 37:58-65. [PMID: 25263014 DOI: 10.1016/j.semcdb.2014.09.020] [Citation(s) in RCA: 100] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Revised: 09/15/2014] [Accepted: 09/21/2014] [Indexed: 01/19/2023]
Abstract
Metabolic homeostasis requires integration of complex signaling networks which, when deregulated, contribute to metabolic syndrome and related disorders. Protein-tyrosine phosphatase 1B (PTP1B) has emerged as a key regulator of signaling networks that are implicated in metabolic diseases such as obesity and type 2 diabetes. In this review, we examine mechanisms that regulate PTP1B-substrate interaction, enzymatic activity and experimental approaches to identify PTP1B substrates. We then highlight findings that implicate PTP1B in metabolic regulation. In particular, insulin and leptin signaling are discussed as well as recently identified PTP1B substrates that are involved in endoplasmic reticulum stress response, cell-cell communication, energy balance and vesicle trafficking. In summary, PTP1B exhibits exquisite substrate specificity and is an outstanding pharmaceutical target for obesity and type 2 diabetes.
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Affiliation(s)
- Jesse Bakke
- Department of Nutrition, University of California Davis, One Shields Ave, Davis, CA 95616, United States
| | - Fawaz G Haj
- Department of Nutrition, University of California Davis, One Shields Ave, Davis, CA 95616, United States; Division of Endocrinology, Diabetes and Metabolism, Department of Internal Medicine, University of California Davis, Sacramento, CA 95817, United States; Comprehensive Cancer Center, University of California Davis, Sacramento, CA 95817, United States.
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25
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Liu S, Xi Y, Bettaieb A, Matsuo K, Matsuo I, Kulkarni RN, Haj FG. Disruption of protein-tyrosine phosphatase 1B expression in the pancreas affects β-cell function. Endocrinology 2014; 155:3329-38. [PMID: 24956127 PMCID: PMC4138572 DOI: 10.1210/en.2013-2004] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Protein-tyrosine phosphatase 1B (PTP1B) is a physiological regulator of glucose homeostasis and energy balance. However, the role of PTP1B in pancreatic endocrine function remains largely unknown. To investigate the metabolic role of pancreatic PTP1B, we generated mice with pancreas PTP1B deletion (panc-PTP1B KO). Mice were fed regular chow or a high-fat diet, and metabolic parameters, insulin secretion and glucose tolerance were determined. On regular chow, panc-PTP1B KO and control mice exhibited comparable glucose tolerance whereas aged panc-PTP1B KO exhibited mild glucose intolerance. Furthermore, high-fat feeding promoted earlier impairment of glucose tolerance and attenuated glucose-stimulated insulin secretion in panc-PTP1B KO mice. The secretory defect in glucose-stimulated insulin secretion was recapitulated in primary islets ex vivo, suggesting that the effects were likely cell-autonomous. At the molecular level, PTP1B deficiency in vivo enhanced basal and glucose-stimulated tyrosyl phosphorylation of EphA5 in islets. Consistently, PTP1B overexpression in the glucose-responsive MIN6 β-cell line attenuated EphA5 tyrosyl phosphorylation, and substrate trapping identified EphA5 as a PTP1B substrate. In summary, these studies identify a novel role for PTP1B in pancreatic endocrine function.
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Affiliation(s)
- Siming Liu
- Nutrition Department (S.L., Y.X., A.B., K.M., I.M., F.G.H.), University of California Davis, Davis, California 95616; Joslin Diabetes Center (R.N.K.), Department of Medicine, Harvard Medical School, Boston, Massachusetts 02215; and Division of Endocrinology, Diabetes and Metabolism (F.G.H.), Department of Internal Medicine, and Comprehensive Cancer Center, University of California Davis, Sacramento, California 95817
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26
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Prinz WA. Bridging the gap: membrane contact sites in signaling, metabolism, and organelle dynamics. ACTA ACUST UNITED AC 2014; 205:759-69. [PMID: 24958771 PMCID: PMC4068136 DOI: 10.1083/jcb.201401126] [Citation(s) in RCA: 296] [Impact Index Per Article: 29.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Regions of close apposition between two organelles, often referred to as membrane contact sites (MCSs), mostly form between the endoplasmic reticulum and a second organelle, although contacts between mitochondria and other organelles have also begun to be characterized. Although these contact sites have been noted since cells first began to be visualized with electron microscopy, the functions of most of these domains long remained unclear. The last few years have witnessed a dramatic increase in our understanding of MCSs, revealing the critical roles they play in intracellular signaling, metabolism, the trafficking of metabolites, and organelle inheritance, division, and transport.
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Affiliation(s)
- William A Prinz
- Laboratory of Cell and Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
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27
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Barton WA, Dalton AC, Seegar TCM, Himanen JP, Nikolov DB. Tie2 and Eph receptor tyrosine kinase activation and signaling. Cold Spring Harb Perspect Biol 2014; 6:cshperspect.a009142. [PMID: 24478383 DOI: 10.1101/cshperspect.a009142] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The Eph and Tie cell surface receptors mediate a variety of signaling events during development and in the adult organism. As other receptor tyrosine kinases, they are activated on binding of extracellular ligands and their catalytic activity is tightly regulated on multiple levels. The Eph and Tie receptors display some unique characteristics, including the requirement of ligand-induced receptor clustering for efficient signaling. Interestingly, both Ephs and Ties can mediate different, even opposite, biological effects depending on the specific ligand eliciting the response and on the cellular context. Here we discuss the structural features of these receptors, their interactions with various ligands, as well as functional implications for downstream signaling initiation. The Eph/ephrin structures are already well reviewed and we only provide a brief overview on the initial binding events. We go into more detail discussing the Tie-angiopoietin structures and recognition.
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Affiliation(s)
- William A Barton
- Department of Biochemistry and Molecular Biology, School of Medicine, Virginia Commonwealth University, Richmond, Virginia 23298
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28
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Keane N, Freeman C, Swords R, Giles FJ. EPHA3 as a novel therapeutic target in the hematological malignancies. Expert Rev Hematol 2014; 5:325-40. [DOI: 10.1586/ehm.12.19] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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29
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30
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Arregui CO, González Á, Burdisso JE, González Wusener AE. Protein tyrosine phosphatase PTP1B in cell adhesion and migration. Cell Adh Migr 2013; 7:418-23. [PMID: 24104540 DOI: 10.4161/cam.26375] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Cell migration requires a highly coordinated interplay between specialized plasma membrane adhesion complexes and the cytoskeleton. Protein phosphorylation/dephosphorylation modifications regulate many aspects of the integrin-cytoskeleton interdependence, including their coupling, dynamics, and organization to support cell movement. The endoplasmic reticulum-bound protein tyrosine phosphatase PTP1B has been implicated as a regulator of cell adhesion and migration. Recent results from our laboratory shed light on potential mechanisms, such as Src/FAK signaling through Rho GTPases and integrin-cytoskeletal coupling.
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Affiliation(s)
- Carlos O Arregui
- Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico de Chascomús (IIB-INTECH); Universidad Nacional de San Martín; Consejo Nacional de Investigaciones Científicas y Técnicas; Buenos Aires, Argentina
| | - Ángela González
- Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico de Chascomús (IIB-INTECH); Universidad Nacional de San Martín; Consejo Nacional de Investigaciones Científicas y Técnicas; Buenos Aires, Argentina
| | - Juan E Burdisso
- Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico de Chascomús (IIB-INTECH); Universidad Nacional de San Martín; Consejo Nacional de Investigaciones Científicas y Técnicas; Buenos Aires, Argentina
| | - Ana E González Wusener
- Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico de Chascomús (IIB-INTECH); Universidad Nacional de San Martín; Consejo Nacional de Investigaciones Científicas y Técnicas; Buenos Aires, Argentina
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31
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Lisabeth EM, Falivelli G, Pasquale EB. Eph receptor signaling and ephrins. Cold Spring Harb Perspect Biol 2013; 5:5/9/a009159. [PMID: 24003208 DOI: 10.1101/cshperspect.a009159] [Citation(s) in RCA: 281] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The Eph receptors are the largest of the RTK families. Like other RTKs, they transduce signals from the cell exterior to the interior through ligand-induced activation of their kinase domain. However, the Eph receptors also have distinctive features. Instead of binding soluble ligands, they generally mediate contact-dependent cell-cell communication by interacting with surface-associated ligands-the ephrins-on neighboring cells. Eph receptor-ephrin complexes emanate bidirectional signals that affect both receptor- and ephrin-expressing cells. Intriguingly, ephrins can also attenuate signaling by Eph receptors coexpressed in the same cell. Additionally, Eph receptors can modulate cell behavior independently of ephrin binding and kinase activity. The Eph/ephrin system regulates many developmental processes and adult tissue homeostasis. Its abnormal function has been implicated in various diseases, including cancer. Thus, Eph receptors represent promising therapeutic targets. However, more research is needed to better understand the many aspects of their complex biology that remain mysterious.
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Affiliation(s)
- Erika M Lisabeth
- Cancer Center, Sanford-Burnham Medical Research Institute, La Jolla, California 92037, USA
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Protein tyrosine phosphatase receptor type O inhibits trigeminal axon growth and branching by repressing TrkB and Ret signaling. J Neurosci 2013; 33:5399-410. [PMID: 23516305 DOI: 10.1523/jneurosci.4707-12.2013] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Axonal branches of the trigeminal ganglion (TG) display characteristic growth and arborization patterns during development. Subsets of TG neurons express different receptors for growth factors, but these are unlikely to explain the unique patterns of axonal arborizations. Intrinsic modulators may restrict or enhance cellular responses to specific ligands and thereby contribute to the development of axon growth patterns. Protein tyrosine phosphatase receptor type O (PTPRO), which is required for Eph receptor-dependent retinotectal development in chick and for development of subsets of trunk sensory neurons in mouse, may be such an intrinsic modulator of TG neuron development. PTPRO is expressed mainly in TrkB-expressing (TrkB(+)) and Ret(+) mechanoreceptors within the TG during embryogenesis. In PTPRO mutant mice, subsets of TG neurons grow longer and more elaborate axonal branches. Cultured PTPRO(-/-) TG neurons display enhanced axonal outgrowth and branching in response to BDNF and GDNF compared with control neurons, indicating that PTPRO negatively controls the activity of BDNF/TrkB and GDNF/Ret signaling. Mouse PTPRO fails to regulate Eph signaling in retinocollicular development and in hindlimb motor axon guidance, suggesting that chick and mouse PTPRO have different substrate specificities. PTPRO has evolved to fine tune growth factor signaling in a cell-type-specific manner and to thereby increase the diversity of signaling output of a limited number of receptor tyrosine kinases to control the branch morphology of developing sensory neurons. The regulation of Eph receptor-mediated developmental processes by protein tyrosine phosphatases has diverged between chick and mouse.
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Nikolov DB, Xu K, Himanen JP. Eph/ephrin recognition and the role of Eph/ephrin clusters in signaling initiation. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2013; 1834:2160-5. [PMID: 23628727 DOI: 10.1016/j.bbapap.2013.04.020] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Revised: 04/17/2013] [Accepted: 04/19/2013] [Indexed: 11/15/2022]
Abstract
The Eph receptors and their ephrin ligands play crucial roles in a large number of cell-cell interaction events, including those associated with axon pathfinding, neuronal cell migration and vasculogenesis. They are also involved in the patterning of most tissues and overall cell positioning in the development of the vertebrate body plan. The Eph/ephrin signaling system manifests several unique features that differentiate it from other receptor tyrosine kinases, including initiation of bi-directional signaling cascades and the existence of ligand and receptor subclasses displaying promiscuous intra-subclass interactions, but very rare inter-subclass interactions. In this review we briefly discuss these features and focus on recent studies of the unique and expansive high-affinity Eph/ephrin assemblies that form at the sites of cell-cell contact and are required for Eph signaling initiation. This article is part of a Special Issue entitled: Emerging recognition and activation mechanisms of receptor tyrosine kinases.
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Affiliation(s)
- Dimitar B Nikolov
- Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, USA.
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Stefan CJ, Manford AG, Emr SD. ER-PM connections: sites of information transfer and inter-organelle communication. Curr Opin Cell Biol 2013; 25:434-42. [PMID: 23522446 DOI: 10.1016/j.ceb.2013.02.020] [Citation(s) in RCA: 159] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Revised: 02/25/2013] [Accepted: 02/28/2013] [Indexed: 11/18/2022]
Abstract
Eukaryotic cells are divided into distinct membrane-bound organelles with unique identities and specialized metabolic functions. Communication between organelles must take place to regulate the size, shape, and composition of individual organelles, as well as to coordinate transport between organelles. The endoplasmic reticulum (ER) forms an expansive membrane network that contacts and participates in crosstalk with several other organelles in the cell, most notably the plasma membrane (PM). ER-PM junctions have well-established functions in the movement of small molecules, such as lipids and ions, between the ER and PM. Recent discoveries have revealed additional exciting roles for ER-PM junctions in the regulation of cell signaling, ER shape and architecture, and PM domain organization.
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Affiliation(s)
- Christopher J Stefan
- Weill Institute for Cell & Molecular Biology, Department of Molecular Biology & Genetics, Cornell University, Ithaca, NY 14853, United States.
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35
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Courilleau C, Chailleux C, Jauneau A, Grimal F, Briois S, Boutet-Robinet E, Boudsocq F, Trouche D, Canitrot Y. The chromatin remodeler p400 ATPase facilitates Rad51-mediated repair of DNA double-strand breaks. ACTA ACUST UNITED AC 2013; 199:1067-81. [PMID: 23266955 PMCID: PMC3529529 DOI: 10.1083/jcb.201205059] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The chromatin remodeling enzyme p400 forms a complex with Rad51 and is required for its recruitment to double-strand breaks during DNA repair by homologous recombination. DNA damage signaling and repair take place in a chromatin context. Consequently, chromatin-modifying enzymes, including adenosine triphosphate–dependent chromatin remodeling enzymes, play an important role in the management of DNA double-strand breaks (DSBs). Here, we show that the p400 ATPase is required for DNA repair by homologous recombination (HR). Indeed, although p400 is not required for DNA damage signaling, DNA DSB repair is defective in the absence of p400. We demonstrate that p400 is important for HR-dependent processes, such as recruitment of Rad51 to DSB (a key component of HR), homology-directed repair, and survival after DNA damage. Strikingly, p400 and Rad51 are present in the same complex and both favor chromatin remodeling around DSBs. Altogether, our data provide a direct molecular link between Rad51 and a chromatin remodeling enzyme involved in chromatin decompaction around DNA DSBs.
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Affiliation(s)
- Céline Courilleau
- Laboratoire de Biologie Cellulaire et Moléculaire du Contrôle de la Prolifération, UMR 5088, Université de Toulouse and 2 Centre National de la Recherche Scientifique, Université Paul Sabatier, 31062 Toulouse, France
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The nucleus- and endoplasmic reticulum-targeted forms of protein tyrosine phosphatase 61F regulate Drosophila growth, life span, and fecundity. Mol Cell Biol 2013; 33:1345-56. [PMID: 23339871 DOI: 10.1128/mcb.01411-12] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The protein tyrosine phosphatases (PTPs) T cell PTP (TCPTP) and PTP1B share a high level of catalytic domain sequence and structural similarity yet display distinct differences in substrate recognition and function. Their noncatalytic domains contribute to substrate selectivity and function by regulating TCPTP nucleocytoplasmic shuttling and targeting PTP1B to the endoplasmic reticulum (ER). The Drosophila TCPTP/PTP1B orthologue PTP61F has two variants with identical catalytic domains that are differentially targeted to the ER and nucleus. Here we demonstrate that the PTP61F variants differ in their ability to negatively regulate insulin signaling in vivo, with the nucleus-localized form (PTP61Fn) being more effective than the ER-localized form (PTP61Fm). We report that PTP61Fm is reliant on the adaptor protein Dock to attenuate insulin signaling in vivo. Also, we show that the PTP61F variants differ in their capacities to regulate growth, with PTP61Fn but not PTP61Fm attenuating cellular proliferation. Furthermore, we generate a mutant lacking both PTP61F variants, which displays a reduction in median life span and a decrease in female fecundity, and show that both variants are required to rescue these mutant phenotypes. Our findings define the role of PTP61F in life span and fecundity and reinforce the importance of subcellular localization in mediating PTP function in vivo.
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Lahtela J, Corson LB, Hemmes A, Brauer MJ, Koopal S, Lee J, Hunsaker TL, Jackson PK, Verschuren EW. A high-content cellular senescence screen identifies candidate tumor suppressors, including EPHA3. Cell Cycle 2013; 12:625-34. [PMID: 23324396 PMCID: PMC3594263 DOI: 10.4161/cc.23515] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Activation of a cellular senescence program is a common response to prolonged oncogene activation or tumor suppressor loss, providing a physiological mechanism for tumor suppression in premalignant cells. The link between senescence and tumor suppression supports the hypothesis that a loss-of-function screen measuring bona fide senescence marker activation should identify candidate tumor suppressors. Using a high-content siRNA screening assay for cell morphology and proliferation measures, we identify 12 senescence-regulating kinases and determine their senescence marker signatures, including elevation of senescence-associated β-galactosidase, DNA damage and p53 or p16INK4a expression. Consistent with our hypothesis, SNP array CGH data supports loss of gene copy number of five senescence-suppressing genes across multiple tumor samples. One such candidate is the EPHA3 receptor tyrosine kinase, a gene commonly mutated in human cancer. We demonstrate that selected intracellular EPHA3 tumor-associated point mutations decrease receptor expression level and/or receptor tyrosine kinase (RTK) activity. Our study therefore describes a new strategy to mine for novel candidate tumor suppressors and provides compelling evidence that EPHA3 mutations may promote tumorigenesis only when key senescence-inducing pathways have been inactivated.
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Affiliation(s)
- Jenni Lahtela
- Institute for Molecular Medicine Finland (FIMM), University of Helsinki, Helsinki, Finland
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Burdisso JE, González Á, Arregui CO. PTP1B promotes focal complex maturation, lamellar persistence and directional migration. J Cell Sci 2013; 126:1820-31. [DOI: 10.1242/jcs.118828] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Previous findings established that ER-bound PTP1B targets peripheral cell-matrix adhesions and regulates positively cell adhesion to fibronectin. Here we show that PTP1B enhances focal complex lifetime at the lamellipodium base, delaying their turnover and facilitating α-actinin incorporation. We demonstrate the presence of catalytic PTP1BD181A-α-actinin complexes at focal complexes. Kymograph analysis reveals that PTP1B contributes to lamellar protrusion persistence and directional cell migration. Pull down and FRET analysis also shows that PTP1B is required for efficient integrin-dependent downregulation of RhoA and upregulation of Rac1 during spreading. A substrate trap strategy revealed that FAK/Src recruitment and Src activity were essential for the generation of PTP1B substrates in adhesions. PTP1B targets the negative regulatory site of Src (phosphotyrosine 529), paxillin and p130Cas at peripheral cell-matrix adhesions. We postulate that PTP1B modulates more than one pathway required for focal complex maturation and membrane protrusion, including α-actinin-mediated cytoskeletal anchorage, integrin-dependent activation of the FAK/Src signaling pathway, and RhoA and Rac1 GTPase activity. By doing so, PTP1B contributes to coordinate adhesion turnover, lamellar stability and directional cell migration.
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Atapattu L, Saha N, Llerena C, Vail ME, Scott AM, Nikolov DB, Lackmann M, Janes PW. Antibodies binding the ADAM10 substrate recognition domain inhibit Eph function. J Cell Sci 2012; 125:6084-93. [PMID: 23108669 DOI: 10.1242/jcs.112631] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The ADAM10 transmembrane metalloprotease cleaves a variety of cell surface proteins that are important in disease, including ligands for receptor tyrosine kinases of the erbB and Eph families. ADAM10-mediated cleavage of ephrins, the ligands for Eph receptors, is suggested to control Eph/ephrin-mediated cell-cell adhesion and segregation, important during normal developmental processes, and implicated in tumour neo-angiogenesis and metastasis. We previously identified a substrate-binding pocket in the ADAM10 C domain that binds the EphA/ephrin-A complex thereby regulating ephrin cleavage. We have now generated monoclonal antibodies specifically recognising this region of ADAM10, which inhibit ephrin cleavage and Eph/ephrin-mediated cell function, including ephrin-induced Eph receptor internalisation, phosphorylation and Eph-mediated cell segregation. Our studies confirm the important role of ADAM10 in cell-cell interactions mediated by both A- and B-type Eph receptors, and suggest antibodies against the ADAM10 substrate-recognition pocket as promising therapeutic agents, acting by inhibiting cleavage of ephrins and potentially other ADAM10 substrates.
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Affiliation(s)
- Lakmali Atapattu
- Department of Biochemistry and Molecular Biology, Monash University, Victoria 3800, Australia
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40
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ER-bound protein tyrosine phosphatase PTP1B interacts with Src at the plasma membrane/substrate interface. PLoS One 2012; 7:e38948. [PMID: 22701734 PMCID: PMC3372476 DOI: 10.1371/journal.pone.0038948] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2011] [Accepted: 05/15/2012] [Indexed: 12/17/2022] Open
Abstract
PTP1B is an endoplasmic reticulum (ER) anchored enzyme whose access to substrates is partly dependent on the ER distribution and dynamics. One of these substrates, the protein tyrosine kinase Src, has been found in the cytosol, endosomes, and plasma membrane. Here we analyzed where PTP1B and Src physically interact in intact cells, by bimolecular fluorescence complementation (BiFC) in combination with temporal and high resolution microscopy. We also determined the structural basis of this interaction. We found that BiFC signal is displayed as puncta scattered throughout the ER network, a feature that was enhanced when the substrate trapping mutant PTP1B-D181A was used. Time-lapse and co-localization analyses revealed that BiFC puncta did not correspond to vesicular carriers; instead they localized at the tip of dynamic ER tubules. BiFC puncta were retained in ventral membrane preparations after cell unroofing and were also detected within the evanescent field of total internal reflection fluorescent microscopy (TIRFM) associated to the ventral membranes of whole cells. Furthermore, BiFC puncta often colocalized with dark spots seen by surface reflection interference contrast (SRIC). Removal of Src myristoylation and polybasic motifs abolished BiFC. In addition, PTP1B active site and negative regulatory tyrosine 529 on Src were primary determinants of BiFC occurrence, although the SH3 binding motif on PTP1B also played a role. Our results suggest that ER-bound PTP1B dynamically interacts with the negative regulatory site at the C-terminus of Src at random puncta in the plasma membrane/substrate interface, likely leading to Src activation and recruitment to adhesion complexes. We postulate that this functional ER/plasma membrane crosstalk could apply to a wide array of protein partners, opening an exciting field of research.
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Nievergall E, Lackmann M, Janes PW. Eph-dependent cell-cell adhesion and segregation in development and cancer. Cell Mol Life Sci 2012; 69:1813-42. [PMID: 22204021 PMCID: PMC11114713 DOI: 10.1007/s00018-011-0900-6] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2011] [Revised: 11/06/2011] [Accepted: 11/28/2011] [Indexed: 01/23/2023]
Abstract
Numerous studies attest to essential roles for Eph receptors and their ephrin ligands in controlling cell positioning and tissue patterning during normal and oncogenic development. These studies suggest multiple, sometimes contradictory, functions of Eph-ephrin signalling, which under different conditions can promote either spreading and cell-cell adhesion or cytoskeletal collapse, cell rounding, de-adhesion and cell-cell segregation. A principle determinant of the balance between these two opposing responses is the degree of receptor/ligand clustering and activation. This equilibrium is likely altered in cancers and modulated by somatic mutations of key Eph family members that have emerged as candidate cancer markers in recent profiling studies. In addition, cross-talk amongst Ephs and with other signalling pathways significantly modulates cell-cell adhesion, both between and within Eph- and ephrin-expressing cell populations. This review summarises our current understanding of how Eph receptors control cell adhesion and morphology, and presents examples demonstrating the importance of these events in normal development and cancer.
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Affiliation(s)
- Eva Nievergall
- Department of Biochemistry and Molecular Biology, Monash University, Wellington Road, Clayton, VIC 3800 Australia
- Present Address: Haematology Department, SA Pathology, Frome Road, Adelaide, SA 5000 Australia
| | - Martin Lackmann
- Department of Biochemistry and Molecular Biology, Monash University, Wellington Road, Clayton, VIC 3800 Australia
| | - Peter W. Janes
- Department of Biochemistry and Molecular Biology, Monash University, Wellington Road, Clayton, VIC 3800 Australia
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42
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Haj FG, Sabet O, Kinkhabwala A, Wimmer-Kleikamp S, Roukos V, Han HM, Grabenbauer M, Bierbaum M, Antony C, Neel BG, Bastiaens PI. Regulation of signaling at regions of cell-cell contact by endoplasmic reticulum-bound protein-tyrosine phosphatase 1B. PLoS One 2012; 7:e36633. [PMID: 22655028 PMCID: PMC3360045 DOI: 10.1371/journal.pone.0036633] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Accepted: 04/04/2012] [Indexed: 12/17/2022] Open
Abstract
Protein-tyrosine phosphatase 1B (PTP1B) is a ubiquitously expressed PTP that is anchored to the endoplasmic reticulum (ER). PTP1B dephosphorylates activated receptor tyrosine kinases after endocytosis, as they transit past the ER. However, PTP1B also can access some plasma membrane (PM)-bound substrates at points of cell-cell contact. To explore how PTP1B interacts with such substrates, we utilized quantitative cellular imaging approaches and mathematical modeling of protein mobility. We find that the ER network comes in close proximity to the PM at apparently specialized regions of cell-cell contact, enabling PTP1B to engage substrate(s) at these sites. Studies using PTP1B mutants show that the ER anchor plays an important role in restricting its interactions with PM substrates mainly to regions of cell-cell contact. In addition, treatment with PTP1B inhibitor leads to increased tyrosine phosphorylation of EphA2, a PTP1B substrate, specifically at regions of cell-cell contact. Collectively, our results identify PM-proximal sub-regions of the ER as important sites of cellular signaling regulation by PTP1B.
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Affiliation(s)
- Fawaz G. Haj
- Beth Israel Deaconess Medical Center, Harvard University, Boston, Massachusetts, United States of America
- Nutrition Department, University of California Davis, Davis, California, United States of America
- * E-mail: (FGH) (FH); (BGN) (BN); (PIB) (PB)
| | - Ola Sabet
- Department of Systemic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Ali Kinkhabwala
- Department of Systemic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Sabine Wimmer-Kleikamp
- Department of Systemic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Vassilis Roukos
- Department of Systemic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Hong-Mei Han
- Department of Systemic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Markus Grabenbauer
- Department of Systemic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Martin Bierbaum
- Department of Systemic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Claude Antony
- European Molecular Biology Laboratories, Heidelberg, Germany
| | - Benjamin G. Neel
- Beth Israel Deaconess Medical Center, Harvard University, Boston, Massachusetts, United States of America
- Campbell Family Cancer Research Institute, Ontario Cancer Institute, Princess Margaret Hospital, University Health Network, and Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
- * E-mail: (FGH) (FH); (BGN) (BN); (PIB) (PB)
| | - Philippe I. Bastiaens
- Department of Systemic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
- * E-mail: (FGH) (FH); (BGN) (BN); (PIB) (PB)
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Xu Q, Lin WC, Petit RS, Groves JT. EphA2 receptor activation by monomeric Ephrin-A1 on supported membranes. Biophys J 2012; 101:2731-9. [PMID: 22261062 DOI: 10.1016/j.bpj.2011.10.039] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2011] [Revised: 10/07/2011] [Accepted: 10/31/2011] [Indexed: 01/22/2023] Open
Abstract
The receptor tyrosine kinase EphA2 interacts with its glycosylphosphatidylinositol (GPI)-linked ephrin-A1 ligand in a juxtacrine configuration. The soluble ephrin-A1 protein, without its GPI membrane linker, fails to activate EphA2. However, preclustered ephrin-A1 protein is active in solution and has been frequently used to trigger the EphA2 receptor. Although this approach has yielded insights into EphA2 signaling, preclustered ligands bypass natural receptor clustering processes and thus mask any role of clustering as a signal regulatory mechanism. Here, we present EphA2-expressing cells with a fusion protein of monomeric ephrin-A1 (mEA1) and enhanced monomeric yellow fluorescent protein that is linked to a supported lipid bilayer via a nickel-decahistidine anchor. The mEA1 is homogeneously dispersed, laterally mobile, and monomeric as measured by fluorescence imaging, correlation spectroscopy, and photon counting histogram analysis, respectively. Ephrin-A1 presented in this manner activates EphA2 on the surface of MDA-MB-231 human breast cancer cells, as measured by EphA2 phosphorylation and degradation. Spatial mutation experiments in which nanopatterns on the underlying substrate restrict mEA1 movement in the supported lipid bilayer reveal spatio-mechanical regulation of this signaling pathway, consistent with recently reported observations using a synthetically cross-linked ephrin-A1 dimer.
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Affiliation(s)
- Qian Xu
- Howard Hughes Medical Institute, Department of Chemistry, University of California, Berkeley, California, USA
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44
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Numata T, Sato K, Christmann J, Marx R, Mori Y, Okada Y, Wehner F. The ΔC splice-variant of TRPM2 is the hypertonicity-induced cation channel in HeLa cells, and the ecto-enzyme CD38 mediates its activation. J Physiol 2012; 590:1121-38. [PMID: 22219339 PMCID: PMC3381820 DOI: 10.1113/jphysiol.2011.220947] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2011] [Accepted: 12/31/2011] [Indexed: 12/13/2022] Open
Abstract
Hypertonicity-induced cation channels (HICCs) are key-players in proliferation and apoptosis but their molecular correlate remains obscure. Furthermore, the activation profile of HICCs is not well defined yet. We report here that, in HeLa cells, intracellular adenosine diphosphate ribose (ADPr) and cyclic ADPr (cADPr), as supposed activators of TRPM2, elicited cation currents that were virtually identical to the osmotic activation of HICCs. Silencing of the expression of TRPM2 and of the ecto-enzyme CD38 (as a likely source of ADPr and cADPr) inhibited HICC as well as nucleotide-induced currents and, in parallel, the hypertonic volume response of cells (the regulatory volume increase, RVI) was attenuated. Quantification of intracellular cADPr levels and the systematic application of extra- vs. intracellular nucleotides indicate that the outwardly directed gradient rather than the cellular activity of ADPr and cADPr triggers TRPM2 activation, probably along with a simultaneous biotransformation of nucleotides.Cloning of TRPM2 identified the ΔC-splice variant as the molecular correlate of the HICC, which could be strongly supported by a direct comparison of the respective Ca²⁺ selectivity. Finally, immunoprecipitation and high-resolution FRET/FLIM imaging revealed the interaction of TRPM2 and CD38 in the native as well as in a heterologous (HEK293T) expression system. We propose transport-related nucleotide export via CD38 as a novel mechanism of TRPM2/HICC activation. With the biotransformation of nucleotides running in parallel, continuous zero trans-conditions are achieved which will render the system infinitely sensitive.
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Affiliation(s)
- Tomohiro Numata
- Department of Cell Physiology, National Institute of Physiological Sciences, Okazaki 444–8585, Japan
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45
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Lisabeth EM, Fernandez C, Pasquale EB. Cancer somatic mutations disrupt functions of the EphA3 receptor tyrosine kinase through multiple mechanisms. Biochemistry 2012; 51:1464-75. [PMID: 22242939 DOI: 10.1021/bi2014079] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The Eph receptor tyrosine kinases make up an important family of signal transduction molecules that control many cellular processes, including cell adhesion and movement, cell shape, and cell growth. All of these are important aspects of cancer progression, but the relationship between Eph receptors and cancer is complex and not fully understood. Genetic screens of tumor specimens from cancer patients have revealed somatic mutations in many Eph receptors. The most highly mutated Eph receptor is EphA3, but its functional role in cancer is currently not well established. Here we show that many EphA3 mutations identified in lung, colorectal, and hepatocellular cancers, melanoma, and glioblastoma impair kinase activity or ephrin ligand binding and/or decrease the level of receptor cell surface localization. These results suggest that EphA3 has ephrin- and kinase-dependent tumor suppressing activities, which are disrupted by somatic cancer mutations.
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Affiliation(s)
- Erika M Lisabeth
- Sanford-Burnham Medical Research Institute, 10901 North Torrey Pines Road, La Jolla, California 92037, United States
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46
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T-cell protein tyrosine phosphatase regulates bone resorption and whole-body insulin sensitivity through its expression in osteoblasts. Mol Cell Biol 2012; 32:1080-8. [PMID: 22252315 DOI: 10.1128/mcb.06279-11] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Insulin signaling in osteoblasts contributes to whole-body glucose homeostasis in the mouse and in humans by increasing the activity of osteocalcin. The osteoblast insulin signaling cascade is negatively regulated by ESP, a tyrosine phosphatase dephosphorylating the insulin receptor. Esp is one of many tyrosine phosphatases expressed in osteoblasts, and this observation suggests that other protein tyrosine phosphatases (PTPs) may contribute to the attenuation of insulin receptor phosphorylation in this cell type. In this study, we sought to identify an additional PTP(s) that, like ESP, would function in the osteoblast to regulate insulin signaling and thus affect activity of the insulin-sensitizing hormone osteocalcin. For that purpose, we used as criteria expression in osteoblasts, regulation by isoproterenol, and ability to trap the insulin receptor in a substrate-trapping assay. Here we show that the T-cell protein tyrosine phosphatase (TC-PTP) regulates insulin receptor phosphorylation in the osteoblast, thus compromising bone resorption and bioactivity of osteocalcin. Accordingly, osteoblast-specific deletion of TC-PTP promotes insulin sensitivity in an osteocalcin-dependent manner. This study increases the number of genes involved in the bone regulation of glucose homeostasis.
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47
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Concepts and consequences of Eph receptor clustering. Semin Cell Dev Biol 2012; 23:43-50. [PMID: 22261642 DOI: 10.1016/j.semcdb.2012.01.001] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2012] [Accepted: 01/04/2012] [Indexed: 12/31/2022]
Abstract
Polymeric receptor-ligand complexes between interacting Eph and ephrin-expressing cells are regarded as dynamic intercellular signalling scaffolds that control cell-to-cell contact: the resulting Eph-ephrin signalling clusters function as positional cues that facilitate cell navigation and tissue patterning during normal and oncogenic development. The considerable complexity of this task, coordinating a multitude of cell movements and cellular interactions, is achieved by accurate translation of spatial information from Eph and ephrin expression gradients into fine-tuned changes in cell-cell adhesion and position. Here we review emerging evidence suggesting that the required combinatorial diversity is not only achieved by the large number of possible Eph-ephrin interactions and selective use of Eph forward and ephrin reverse signals, but in particular through the composition and signal capacity of Eph-ephrin clusters, which is adjusted dynamically to reflect overall Eph and ephrin surface densities on interacting cells. Fine-tuning is provided through multi-layered cluster assembly, where homo- and heterotypic Eph and ephrin interactions define the composition - whilst intracellular signalling feedbacks determine the size and lifetime - of signalling clusters.
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Singh A, Winterbottom E, Daar IO. Eph/ephrin signaling in cell-cell and cell-substrate adhesion. Front Biosci (Landmark Ed) 2012; 17:473-97. [PMID: 22201756 DOI: 10.2741/3939] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Cell-cell and cell-matrix adhesion are critical processes for the formation and maintenance of tissue patterns during development, as well as control of invasion and metastasis of cancer cells. Although great strides have been made regarding our understanding of the processes that play a role in cell adhesion and cell movement, the precise mechanisms by which diverse signaling events regulate cell and tissue architecture are poorly understood. One group of cell surface molecules, Eph receptor tyrosine kinases, and their membrane-bound ligands, ephrins, are key regulators in these processes. It is the ability of Eph/ephrin signaling pathways to regulate cell-cell adhesion and motility that establishes this family as a formidable system for regulating tissue separation and morphogenesis. Moreover, the de-regulation of this signaling system is linked to the promotion of more aggressive and metastatic tumors in humans.
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Affiliation(s)
- Arvinder Singh
- Laboratory of Cell and Developmental Signaling, National Cancer Institute-Frederick, Frederick, Maryland 21702, USA
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Janes PW, Griesshaber B, Atapattu L, Nievergall E, Hii LL, Mensinga A, Chheang C, Day BW, Boyd AW, Bastiaens PI, Jørgensen C, Pawson T, Lackmann M. Eph receptor function is modulated by heterooligomerization of A and B type Eph receptors. ACTA ACUST UNITED AC 2011; 195:1033-45. [PMID: 22144690 PMCID: PMC3241718 DOI: 10.1083/jcb.201104037] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Beyond homotypic receptor interactions that are required for Eph signaling, ligand-independent association and crosstalk between members of the EphA and -B subclasses determine cell signaling outcomes. Eph receptors interact with ephrin ligands on adjacent cells to facilitate tissue patterning during normal and oncogenic development, in which unscheduled expression and somatic mutations contribute to tumor progression. EphA and B subtypes preferentially bind A- and B-type ephrins, respectively, resulting in receptor complexes that propagate via homotypic Eph–Eph interactions. We now show that EphA and B receptors cocluster, such that specific ligation of one receptor promotes recruitment and cross-activation of the other. Remarkably, coexpression of a kinase-inactive mutant EphA3 with wild-type EphB2 can cause either cross-activation or cross-inhibition, depending on relative expression. Our findings indicate that cellular responses to ephrin contact are determined by the EphA/EphB receptor profile on a given cell rather than the individual Eph subclass. Importantly, they imply that in tumor cells coexpressing different Ephs, functional mutations in one subtype may cause phenotypes that are a result of altered signaling from heterotypic rather from homotypic Eph clusters.
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Affiliation(s)
- Peter W Janes
- Department of Biochemistry and Molecular Biology, Monash University, Victoria 3800, Australia
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Haque A, Andersen JN, Salmeen A, Barford D, Tonks NK. Conformation-sensing antibodies stabilize the oxidized form of PTP1B and inhibit its phosphatase activity. Cell 2011; 147:185-98. [PMID: 21962515 DOI: 10.1016/j.cell.2011.08.036] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2011] [Revised: 06/30/2011] [Accepted: 08/15/2011] [Indexed: 01/10/2023]
Abstract
Protein tyrosine phosphatase 1B (PTP1B) plays important roles in downregulation of insulin and leptin signaling and is an established therapeutic target for diabetes and obesity. PTP1B is regulated by reactive oxygen species (ROS) produced in response to various stimuli, including insulin. The reversibly oxidized form of the enzyme (PTP1B-OX) is inactive and undergoes profound conformational changes at the active site. We generated conformation-sensor antibodies, in the form of single-chain variable fragments (scFvs), that stabilize PTP1B-OX and thereby inhibit its phosphatase function. Expression of conformation-sensor scFvs as intracellular antibodies (intrabodies) enhanced insulin-induced tyrosyl phosphorylation of the β subunit of the insulin receptor and its substrate IRS-1 and increased insulin-induced phosphorylation of PKB/AKT. Our data suggest that stabilization of the oxidized, inactive form of PTP1B with appropriate therapeutic molecules may offer a paradigm for phosphatase drug development.
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Affiliation(s)
- Aftabul Haque
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
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