1
|
Rizzo S, Thévenin D. Identifying Transmembrane Interactions in Receptor Protein Tyrosine Phosphatase Homodimerization and Heterodimerization. Methods Mol Biol 2024; 2743:195-209. [PMID: 38147217 PMCID: PMC10785008 DOI: 10.1007/978-1-0716-3569-8_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2023]
Abstract
Receptor protein tyrosine phosphatases (RPTPs) are one of the key regulators of receptor tyrosine kinases (RTKs) and therefore play a critical role in modulating signal transduction. While the structure-function relationship of RTKs has been widely studied, the mechanisms modulating the activity of RPTPs still need to be fully understood. On the other hand, homodimerization has been shown to antagonize RPTP catalytic activity and appears to be a general feature of the entire family. Conversely, their documented ability to physically interact with RTKs is integral to their negative regulation of RTKs, but there is a yet-to-be proposed common model. However, specific transmembrane (TM) domain interactions and residues have been shown to be essential in regulating RPTP homodimerization, interactions with RTK substrates, and activity. Therefore, elucidating the contribution of the TM domains in RPTP regulation can provide significant insights into how these receptors function, interact, and eventually be modulated. This chapter describes the dominant-negative AraC-based transcriptional reporter (DN-AraTM) assay to identify specific TM interactions essential to homodimerization and heteroassociation with other membrane receptors, such as RTKs.
Collapse
Affiliation(s)
- Sophie Rizzo
- Department of Chemistry, Lehigh University, Bethlehem, PA, USA
| | - Damien Thévenin
- Department of Chemistry, Lehigh University, Bethlehem, PA, USA.
| |
Collapse
|
2
|
Rizzo S, Sikorski E, Park S, Im W, Vasquez‐Montes V, Ladokhin AS, Thévenin D. Promoting the activity of a receptor tyrosine phosphatase with a novel pH-responsive transmembrane agonist inhibits cancer-associated phenotypes. Protein Sci 2023; 32:e4742. [PMID: 37515426 PMCID: PMC10461461 DOI: 10.1002/pro.4742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 07/18/2023] [Accepted: 07/27/2023] [Indexed: 07/30/2023]
Abstract
Cell signaling by receptor protein tyrosine kinases (RTKs) is tightly controlled by the counterbalancing actions of receptor protein tyrosine phosphatases (RPTPs). Due to their role in attenuating the signal-initiating potency of RTKs, RPTPs have long been viewed as therapeutic targets. However, the development of activators of RPTPs has remained limited. We previously reported that the homodimerization of a representative member of the RPTP family (protein tyrosine phosphatase receptor J or PTPRJ) is regulated by specific transmembrane (TM) residues. Disrupting this interaction by single point mutations promotes PTPRJ access to its RTK substrates (e.g., EGFR and FLT3), reduces RTK's phosphorylation and downstream signaling, and ultimately antagonizes RTK-driven cell phenotypes. Here, we designed and tested a series of first-in-class pH-responsive TM peptide agonists of PTPRJ that are soluble in aqueous solution but insert as a helical TM domain in lipid membranes when the pH is lowered to match that of the acidic microenvironment of tumors. The most promising peptide reduced EGFR's phosphorylation and inhibited cancer cell EGFR-driven migration and proliferation, similar to the PTPRJ's TM point mutations. Developing tumor-selective and TM-targeting peptide binders of critical RPTPs could afford a potentially transformative approach to studying RPTP's selectivity mechanism without requiring less specific inhibitors and represent a novel class of therapeutics against RTK-driven cancers.
Collapse
Affiliation(s)
- Sophie Rizzo
- Department of ChemistryLehigh UniversityBethlehemPennsylvaniaUSA
| | - Eden Sikorski
- Department of ChemistryLehigh UniversityBethlehemPennsylvaniaUSA
| | - Soohyung Park
- Department of Biological SciencesLehigh UniversityBethlehemPennsylvaniaUSA
| | - Wonpil Im
- Department of ChemistryLehigh UniversityBethlehemPennsylvaniaUSA
- Department of Biological SciencesLehigh UniversityBethlehemPennsylvaniaUSA
| | - Victor Vasquez‐Montes
- Department of Biochemistry and Molecular BiologyThe University of Kansas Medical CenterKansas CityKansasUSA
| | - Alexey S. Ladokhin
- Department of Biochemistry and Molecular BiologyThe University of Kansas Medical CenterKansas CityKansasUSA
| | - Damien Thévenin
- Department of ChemistryLehigh UniversityBethlehemPennsylvaniaUSA
| |
Collapse
|
3
|
Toledano S, Sabag AD, Ilan N, Liburkin-Dan T, Kessler O, Neufeld G. Plexin-A2 enables the proliferation and the development of tumors from glioblastoma derived cells. Cell Death Dis 2023; 14:41. [PMID: 36658114 PMCID: PMC9852426 DOI: 10.1038/s41419-023-05554-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 12/25/2022] [Accepted: 01/04/2023] [Indexed: 01/20/2023]
Abstract
The semaphorin guidance factors receptor plexin-A2 transduces sema6A and sema6B signals and may mediate, along with plexin-A4, the anti-angiogenic effects of sema6A. When associated with neuropilins plexin-A2 also transduces the anti-angiogenic signals of sema3B. Here we show that inhibition of plexin-A2 expression in glioblastoma derived cells that express wild type p53 such as U87MG and A172 cells, or in primary human endothelial cells, strongly inhibits cell proliferation. Inhibition of plexin-A2 expression in U87MG cells also results in strong inhibition of their tumor forming ability. Knock-out of the plexin-A2 gene in U87MG cells using CRISPR/Cas9 inhibits cell proliferation which is rescued following plexin-A2 re-expression, or expression of a truncated plexin-A2 lacking its extracellular domain. Inhibition of plexin-A2 expression results in cell cycle arrest at the G2/M stage, and is accompanied by changes in cytoskeletal organization, cell flattening, and enhanced expression of senescence associated β-galactosidase. It is also associated with reduced AKT phosphorylation and enhanced phosphorylation of p38MAPK. We find that the pro-proliferative effects of plexin-A2 are mediated by FARP2 and FYN and by the GTPase activating (GAP) domain located in the intracellular domain of plexin-A2. Point mutations in these locations inhibit the rescue of cell proliferation upon re-expression of the mutated intracellular domain in the knock-out cells. In contrast re-expression of a plexin-A2 cDNA containing a point mutation in the semaphorin binding domain failed to inhibit the rescue. Our results suggest that plexin-A2 may represent a novel target for the development of anti-tumorigenic therapeutics.
Collapse
Affiliation(s)
- Shira Toledano
- Cancer research center, The Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, 3109602, Israel
| | - Adi D Sabag
- Division of Allergy & Clinical Immunology, Bnai-Zion medical Center, Haifa, 33394, Israel
| | - Neta Ilan
- Cancer research center, The Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, 3109602, Israel
| | - Tanya Liburkin-Dan
- Cancer research center, The Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, 3109602, Israel
| | - Ofra Kessler
- Cancer research center, The Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, 3109602, Israel
| | - Gera Neufeld
- Cancer research center, The Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, 3109602, Israel.
| |
Collapse
|
4
|
Schwarz M, Rizzo S, Paz WE, Kresinsky A, Thévenin D, Müller JP. Disrupting PTPRJ transmembrane-mediated oligomerization counteracts oncogenic receptor tyrosine kinase FLT3 ITD. Front Oncol 2022; 12:1017947. [PMID: 36452504 PMCID: PMC9701752 DOI: 10.3389/fonc.2022.1017947] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Accepted: 10/25/2022] [Indexed: 11/15/2022] Open
Abstract
The receptor protein tyrosine phosphatase (RPTP) PTPRJ (also known as DEP-1) has been identified as a negative regulator of the receptor tyrosine kinase FLT3 signalling in vitro. The inactivation of the PTPRJ gene in mice expressing the constitutively active, oncogenic receptor tyrosine kinase FLT3 ITD aggravated known features of leukaemogenesis, revealing PTPRJ's antagonistic role. FLT3 ITD mutations resulting in constitutively kinase activity and cell transformation frequently occur in patients with acute myeloid leukaemia (AML). Thus, in situ activation of PTPRJ could be used to abrogate oncogenic FLT3 signalling. The activity of PTPRJ is suppressed by homodimerization, which is mediated by transmembrane domain (TMD) interactions. Specific Glycine-to-Leucine mutations in the TMD disrupt oligomerization and inhibit the Epidermal Growth Factor Receptor (EGFR) and EGFR-driven cancer cell phenotypes. To study the effects of PTPRJ TMD mutant proteins on FLT3 ITD activity in cell lines, endogenous PTPRJ was inactivated and replaced by stable expression of PTPRJ TMD mutants. Autophosphorylation of wild-type and ITD-mutated FLT3 was diminished in AML cell lines expressing the PTPRJ TMD mutants compared to wild-type-expressing cells. This was accompanied by reduced FLT3-mediated global protein tyrosine phosphorylation and downstream signalling. Further, PTPRJ TMD mutant proteins impaired the proliferation and in vitro transformation of leukemic cells. Although PTPRJ's TMD mutant proteins showed impaired self-association, the specific phosphatase activity of immunoprecipitated proteins remained unchanged. In conclusion, this study demonstrates that the destabilization of PTPRJ TMD-mediated self-association increases the activity of PTPRJ in situ and impairs FLT3 activity and FLT3-driven cell phenotypes of AML cells. Thus, disrupting the oligomerization of PTPRJ in situ could prove a valuable therapeutic strategy to restrict oncogenic FLT3 activity in leukemic cells.
Collapse
Affiliation(s)
- Marie Schwarz
- Institute for Molecular Cell Biology, CMB - Center for Molecular Biomedicine, University Hospital Jena, Jena, Germany
| | - Sophie Rizzo
- Department of Chemistry, Lehigh University, Bethlehem, PA, United States
| | | | - Anne Kresinsky
- Institute for Molecular Cell Biology, CMB - Center for Molecular Biomedicine, University Hospital Jena, Jena, Germany,Leibniz Institute on Aging, Fritz Lipmann Institute, Jena, Germany
| | - Damien Thévenin
- Department of Chemistry, Lehigh University, Bethlehem, PA, United States
| | - Jörg P. Müller
- Institute for Molecular Cell Biology, CMB - Center for Molecular Biomedicine, University Hospital Jena, Jena, Germany,*Correspondence: Jörg P. Müller,
| |
Collapse
|
5
|
Li ZL, Müller-Greven J, Kim S, Tamagnone L, Buck M. Plexin-Bs enhance their GAP activity with a novel activation switch loop generating a cooperative enzyme. Cell Mol Life Sci 2020; 78:1101-1112. [PMID: 32601713 DOI: 10.1007/s00018-020-03571-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 05/24/2020] [Accepted: 06/12/2020] [Indexed: 01/01/2023]
Abstract
Plexins receive guidance cues from semaphorin ligands and transmit their signal through the plasma membrane. This family of proteins is unique amongst single-pass transmembrane receptors as their intracellular regions interact directly with several small GTPases, which regulate cytoskeletal dynamics and cell adhesion. Here, we characterize the GTPase Activating Protein (GAP) function of Plexin-B1 and find that a cooperative GAP activity towards the substrate GTPase, Rap1b, is associated with the N-terminal Juxtamembrane region of Plexin-B1. Importantly, we unveil an activation mechanism of Plexin-B1 by identifying a novel functional loop which partially blocks Rap1b entry into the plexin GAP domain. Consistent with the concept of allokairy developed for other systems, Plexin-B activity is increased by an apparent substrate-mediated cooperative effect. Simulations and mutagenesis suggest the repositioned JM conformation is stabilized by the new activation switch loop when the active site is occupied, giving rise to faster enzymatic turnover and cooperative behavior. The biological implications, essentially those of a threshold behavior for cell migration, are discussed.
Collapse
Affiliation(s)
- Zhen-Lu Li
- Department of Physiology and Biophysics, Case Western Reserve University, School of Medicine, 10900 Euclid Avenue, Cleveland, OH, 44106, USA
| | - Jeannine Müller-Greven
- Department of Physiology and Biophysics, Case Western Reserve University, School of Medicine, 10900 Euclid Avenue, Cleveland, OH, 44106, USA
| | - SoonJeung Kim
- Department of Physiology and Biophysics, Case Western Reserve University, School of Medicine, 10900 Euclid Avenue, Cleveland, OH, 44106, USA
| | - Luca Tamagnone
- School of Medicine, Università Cattolica del Sacro Cuore, 00168, Rome, Italy
| | - Matthias Buck
- Department of Physiology and Biophysics, Case Western Reserve University, School of Medicine, 10900 Euclid Avenue, Cleveland, OH, 44106, USA.
- Department of Pharmacology, Case Western Reserve University, School of Medicine, 10900 Euclid Avenue, Cleveland, OH, 44106, USA.
- Department of Neurosciences, Case Western Reserve University, School of Medicine, 10900 Euclid Avenue, Cleveland, OH, 44106, USA.
- Case Comprehensive Cancer Center, Case Western Reserve University, School of Medicine, 10900 Euclid Avenue, Cleveland, OH, 44106, USA.
| |
Collapse
|
6
|
Gerhart J, Thévenin AF, Bloch E, King KE, Thévenin D. Inhibiting Epidermal Growth Factor Receptor Dimerization and Signaling Through Targeted Delivery of a Juxtamembrane Domain Peptide Mimic. ACS Chem Biol 2018; 13:2623-2632. [PMID: 30133245 DOI: 10.1021/acschembio.8b00555] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Overexpression and deregulation of the epidermal growth factor receptor (EGFR) are implicated in multiple human cancers and therefore are a focus for the development of therapeutics. Current strategies aimed at inhibiting EGFR activity include monoclonal antibodies and tyrosine kinase inhibitors. However, activating mutations severely limit the efficacy of these therapeutics. There is thus a growing need for novel methods to inhibit EGFR. One promising approach involves blocking the association of the cytoplasmic juxtamembrane (JM) domain of EGFR, which has been shown to be essential for receptor dimerization and kinase function. Here, we aim to improve the selectivity and efficacy of an EGFR JM peptide mimic by utilizing the pH(low) insertion peptide (pHLIP), a unique molecule that can selectively target cancer cells solely based on their extracellular acidity. This delivery strategy potentially allows for more selective targeting to tumors than current methods and for anchoring the peptide mimic to the cytoplasmic leaflet of the plasma membrane, increasing its local concentration and thus efficacy. We show that the conjugated construct is capable of inhibiting EGFR phosphorylation and downstream signaling and of inducing concentration- and pH-dependent toxicity in cervical cancer cells. We envision that this approach could be expanded to the modulation of other single-span membrane receptors whose activity is mediated by JM domains.
Collapse
Affiliation(s)
- Janessa Gerhart
- Department of Chemistry, Lehigh University, 6 East Packer Avenue, Bethlehem, Pennsylvania 18015, United States
| | - Anastasia F. Thévenin
- Department of Chemistry, Lehigh University, 6 East Packer Avenue, Bethlehem, Pennsylvania 18015, United States
| | - Elizabeth Bloch
- Department of Chemistry, Lehigh University, 6 East Packer Avenue, Bethlehem, Pennsylvania 18015, United States
| | - Kelly E. King
- Department of Chemistry, Lehigh University, 6 East Packer Avenue, Bethlehem, Pennsylvania 18015, United States
| | - Damien Thévenin
- Department of Chemistry, Lehigh University, 6 East Packer Avenue, Bethlehem, Pennsylvania 18015, United States
| |
Collapse
|
7
|
Abstract
Axon guidance relies on a combinatorial code of receptor and ligand interactions that direct adhesive/attractive and repulsive cellular responses. Recent structural data have revealed many of the molecular mechanisms that govern these interactions and enabled the design of sophisticated mutant tools to dissect their biological functions. Here, we discuss the structure/function relationships of four major classes of guidance cues (ephrins, semaphorins, slits, netrins) and examples of morphogens (Wnt, Shh) and of cell adhesion molecules (FLRT). These cell signaling systems rely on specific modes of receptor-ligand binding that are determined by selective binding sites; however, defined structure-encoded receptor promiscuity also enables cross talk between different receptor/ligand families and can also involve extracellular matrix components. A picture emerges in which a multitude of highly context-dependent structural assemblies determines the finely tuned cellular behavior required for nervous system development.
Collapse
Affiliation(s)
- Elena Seiradake
- Department of Biochemistry, Oxford University, Oxford OX1 3QU, United Kingdom;
| | - E Yvonne Jones
- Wellcome Trust Centre for Human Genetics, Oxford University, Oxford OX3 7BN, United Kingdom;
| | - Rüdiger Klein
- Max Planck Institute of Neurobiology, 82152 Munich-Martinsried, Germany;
- Munich Cluster for Systems Neurology (SyNergy), 81377 Munich, Germany
| |
Collapse
|
8
|
Barton R, Khakbaz P, Bera I, Klauda JB, Iovine MK, Berger BW. Interplay of Specific Trans- and Juxtamembrane Interfaces in Plexin A3 Dimerization and Signal Transduction. Biochemistry 2016; 55:4928-38. [PMID: 27508400 DOI: 10.1021/acs.biochem.6b00517] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Plexins are transmembrane proteins that serve as guidance receptors during angiogenesis, lymphangiogenesis, neuronal development, and zebrafish fin regeneration, with a putative role in cancer metastasis. Receptor dimerization or clustering, induced by extracellular ligand binding but modulated in part by the plexin transmembrane (TM) and juxtamembrane (JM) domains, is thought to drive plexin activity. Previous studies indicate that isolated plexin TM domains interact through a conserved, small-x3-small packing motif, and the cytosolic JM region interacts through a hydrophobic heptad repeat; however, the roles and interplay of these regions in plexin signal transduction remain unclear. Using an integrated experimental and simulation approach, we find disruption of the small-x3-small motifs in the Danio rerio Plexin A3 TM domain enhances dimerization of the TM-JM domain by enhancing JM-mediated dimerization. Furthermore, mutations of the cytosolic JM heptad repeat that disrupt dimerization do so even in the presence of TM domain mutations. However, mutations to the small-x3-small TM interfaces also disrupt Plexin A3 signaling in a zebrafish axonal guidance assay, indicating the importance of this TM interface in signal transduction. Collectively, our experimental and simulation results demonstrate that multiple TM and JM interfaces exist in the Plexin A3 homodimer, and these interfaces independently regulate dimerization that is important in Plexin A3 signal transduction.
Collapse
Affiliation(s)
- Rachael Barton
- Department of Chemical and Biomolecular Engineering, Lehigh University , Bethlehem, Pennsylvania 18015, United States
| | - Pouyan Khakbaz
- Department of Chemical and Biomolecular Engineering, University of Maryland , College Park, Maryland 20742, United States
| | - Indrani Bera
- Department of Chemical and Biomolecular Engineering, University of Maryland , College Park, Maryland 20742, United States
| | - Jeffery B Klauda
- Department of Chemical and Biomolecular Engineering, University of Maryland , College Park, Maryland 20742, United States.,Biophysics Program, University of Maryland , College Park, Maryland 20742-2431, United States
| | - M Kathryn Iovine
- Department of Biological Sciences, Lehigh University , Bethlehem, Pennsylvania 18015, United States
| | - Bryan W Berger
- Department of Chemical and Biomolecular Engineering, Lehigh University , Bethlehem, Pennsylvania 18015, United States.,Program in Bioengineering, Lehigh University , Bethlehem, Pennsylvania 18015, United States
| |
Collapse
|
9
|
Deng W, Li R. Juxtamembrane contribution to transmembrane signaling. Biopolymers 2016; 104:317-22. [PMID: 25846274 DOI: 10.1002/bip.22651] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Revised: 03/23/2015] [Accepted: 03/30/2015] [Indexed: 12/11/2022]
Abstract
Signaling across the cell membrane mediated by transmembrane receptors plays an important role in diverse biological processes. Recent studies have indicated that, in a number of single-span transmembrane receptors, the intracellular juxtamembrane (JM) sequence linking the transmembrane helix with the rest of the cytoplasmic domain participates directly in the signaling process via several novel mechanisms. This review briefly highlights several modes of JM dynamics in the context of signal transduction that are shared by different types of transmembrane receptors.
Collapse
Affiliation(s)
- Wei Deng
- Department of Pediatrics, Aflac Cancer and Blood Disorders Center, Emory University School of Medicine, Atlanta, GA, 30322
| | - Renhao Li
- Department of Pediatrics, Aflac Cancer and Blood Disorders Center, Emory University School of Medicine, Atlanta, GA, 30322
| |
Collapse
|