1
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Woods VA, Abzalimov RR, Keedy DA. Native dynamics and allosteric responses in PTP1B probed by high-resolution HDX-MS. Protein Sci 2024; 33:e5024. [PMID: 38801229 PMCID: PMC11129624 DOI: 10.1002/pro.5024] [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: 11/14/2023] [Revised: 03/27/2024] [Accepted: 05/02/2024] [Indexed: 05/29/2024]
Abstract
Protein tyrosine phosphatase 1B (PTP1B) is a validated therapeutic target for obesity, diabetes, and certain types of cancer. In particular, allosteric inhibitors hold potential for therapeutic use, but an incomplete understanding of conformational dynamics and allostery in this protein has hindered their development. Here, we interrogate solution dynamics and allosteric responses in PTP1B using high-resolution hydrogen-deuterium exchange mass spectrometry (HDX-MS), an emerging and powerful biophysical technique. Using HDX-MS, we obtain a detailed map of backbone amide exchange that serves as a proxy for the solution dynamics of apo PTP1B, revealing several flexible loops interspersed among more constrained and rigid regions within the protein structure, as well as local regions that exchange faster than expected from their secondary structure and solvent accessibility. We demonstrate that our HDX rate data obtained in solution adds value to estimates of conformational heterogeneity derived from a pseudo-ensemble constructed from ~200 crystal structures of PTP1B. Furthermore, we report HDX-MS maps for PTP1B with active-site versus allosteric small-molecule inhibitors. These maps suggest distinct and widespread effects on protein dynamics relative to the apo form, including changes in locations distal (>35 Å) from the respective ligand binding sites. These results illuminate that allosteric inhibitors of PTP1B can induce unexpected changes in dynamics that extend beyond the previously understood allosteric network. Together, our data suggest a model of BB3 allostery in PTP1B that combines conformational restriction of active-site residues with compensatory liberation of distal residues that aid in entropic balancing. Overall, our work showcases the potential of HDX-MS for elucidating aspects of protein conformational dynamics and allosteric effects of small-molecule ligands and highlights the potential of integrating HDX-MS alongside other complementary methods, such as room-temperature X-ray crystallography, NMR spectroscopy, and molecular dynamics simulations, to guide the development of new therapeutics.
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Affiliation(s)
- Virgil A. Woods
- Structural Biology InitiativeCUNY Advanced Science Research CenterNew YorkNew YorkUSA
- PhD Program in BiochemistryCUNY Graduate CenterNew YorkNew YorkUSA
| | - Rinat R. Abzalimov
- Structural Biology InitiativeCUNY Advanced Science Research CenterNew YorkNew YorkUSA
| | - Daniel A. Keedy
- Structural Biology InitiativeCUNY Advanced Science Research CenterNew YorkNew YorkUSA
- Department of Chemistry and BiochemistryCity College of New YorkNew YorkNew YorkUSA
- PhD Programs in Biochemistry, Biology, & ChemistryCUNY Graduate CenterNew YorkNew YorkUSA
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2
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Mehlman T, Ginn HM, Keedy DA. An expanded trove of fragment-bound structures for the allosteric enzyme PTP1B from computational reanalysis of large-scale crystallographic data. Structure 2024:S0969-2126(24)00187-4. [PMID: 38861991 DOI: 10.1016/j.str.2024.05.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2024] [Revised: 04/15/2024] [Accepted: 05/15/2024] [Indexed: 06/13/2024]
Abstract
Due to their low binding affinities, detecting small-molecule fragments bound to protein structures from crystallographic datasets has been a challenge. Here, we report a trove of 65 new fragment hits for PTP1B, an "undruggable" therapeutic target enzyme for diabetes and cancer. These structures were obtained from computational analysis of data from a large crystallographic screen, demonstrating the power of this approach to elucidate many (∼50% more) "hidden" ligand-bound states of proteins. Our new structures include a fragment hit found in a novel binding site in PTP1B with a unique location relative to the active site, one that links adjacent allosteric sites, and, perhaps most strikingly, a fragment that induces long-range allosteric protein conformational responses. Altogether, our research highlights the utility of computational analysis of crystallographic data, makes publicly available dozens of new ligand-bound structures of a high-value drug target, and identifies novel aspects of ligandability and allostery in PTP1B.
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Affiliation(s)
- Tamar Mehlman
- Structural Biology Initiative, CUNY Advanced Science Research Center, New York, NY 10031, USA; PhD Program in Biochemistry, CUNY Graduate Center, New York, NY 10016, USA
| | - Helen M Ginn
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Hamburg, Germany; Institute for Nanostructure and Solid State Physics, Universität Hamburg, Hamburg, Germany; Division of Life Sciences, Diamond Light Source Ltd, Harwell Science and Innovation Campus, Didcot, UK
| | - Daniel A Keedy
- Structural Biology Initiative, CUNY Advanced Science Research Center, New York, NY 10031, USA; Department of Chemistry and Biochemistry, City College of New York, New York, NY 10031, USA; PhD Programs in Biochemistry, Biology, & Chemistry, CUNY Graduate Center, New York, NY 10016, USA.
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3
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Mehlman T(S, Ginn HM, Keedy DA. An expanded view of ligandability in the allosteric enzyme PTP1B from computational reanalysis of large-scale crystallographic data. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.05.574428. [PMID: 38260327 PMCID: PMC10802458 DOI: 10.1101/2024.01.05.574428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
The recent advent of crystallographic small-molecule fragment screening presents the opportunity to obtain unprecedented numbers of ligand-bound protein crystal structures from a single high-throughput experiment, mapping ligandability across protein surfaces and identifying useful chemical footholds for structure-based drug design. However, due to the low binding affinities of most fragments, detecting bound fragments from crystallographic datasets has been a challenge. Here we report a trove of 65 new fragment hits across 59 new liganded crystal structures for PTP1B, an "undruggable" therapeutic target enzyme for diabetes and cancer. These structures were obtained from computational analysis of data from a large crystallographic screen, demonstrating the power of this approach to elucidate many (~50% more) "hidden" ligand-bound states of proteins. Our new structures include a fragment hit found in a novel binding site in PTP1B with a unique location relative to the active site, one that validates another new binding site recently identified by simulations, one that links adjacent allosteric sites, and, perhaps most strikingly, a fragment that induces long-range allosteric protein conformational responses via a previously unreported intramolecular conduit. Altogether, our research highlights the utility of computational analysis of crystallographic data, makes publicly available dozens of new ligand-bound structures of a high-value drug target, and identifies novel aspects of ligandability and allostery in PTP1B.
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Affiliation(s)
- Tamar (Skaist) Mehlman
- Structural Biology Initiative, CUNY Advanced Science Research Center, New York, NY 10031
- PhD Program in Biochemistry, CUNY Graduate Center, New York, NY 10016
| | - Helen M. Ginn
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Hamburg, Germany
- Institute for Nanostructure and Solid State Physics, Universität Hamburg, Hamburg, Germany
- Division of Life Sciences, Diamond Light Source Ltd, Harwell Science and Innovation Campus, Didcot, UK
| | - Daniel A. Keedy
- Structural Biology Initiative, CUNY Advanced Science Research Center, New York, NY 10031
- Department of Chemistry and Biochemistry, City College of New York, New York, NY 10031
- PhD Programs in Biochemistry, Biology, & Chemistry, CUNY Graduate Center, New York, NY 10016
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4
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Woods VA, Abzalimov RR, Keedy DA. Native dynamics and allosteric responses in PTP1B probed by high-resolution HDX-MS. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.12.548582. [PMID: 37503000 PMCID: PMC10369962 DOI: 10.1101/2023.07.12.548582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Protein tyrosine phosphatase 1B (PTP1B) is a validated therapeutic target for obesity, diabetes, and certain types of cancer. In particular, allosteric inhibitors hold potential for therapeutic use, but an incomplete understanding of conformational dynamics and allostery in this protein has hindered their development. Here, we interrogate solution dynamics and allosteric responses in PTP1B using high-resolution hydrogen-deuterium exchange mass spectrometry (HDX-MS), an emerging and powerful biophysical technique. Using HDX-MS, we obtain a detailed map of the solution dynamics of apo PTP1B, revealing several flexible loops interspersed among more constrained and rigid regions within the protein structure, as well as local regions that exchange faster than expected from their secondary structure and buriedness. We demonstrate that our HDX rate data obtained in solution adds value to predictions of dynamics derived from a pseudo-ensemble constructed from ~200 crystal structures of PTP1B. Furthermore, we report HDX-MS maps for PTP1B with active-site vs. allosteric small-molecule inhibitors. These maps reveal distinct, dramatic, and widespread effects on protein dynamics relative to the apo form, including changes to dynamics in locations distal (>35 Å) from the respective ligand binding sites. These results help shed light on the allosteric nature of PTP1B and the surprisingly far-reaching consequences of inhibitor binding in this important protein. Overall, our work showcases the potential of HDX-MS for elucidating protein conformational dynamics and allosteric effects of small-molecule ligands, and highlights the potential of integrating HDX-MS alongside other complementary methods to guide the development of new therapeutics.
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Affiliation(s)
- Virgil A. Woods
- Structural Biology Initiative, CUNY Advanced Science Research Center, New York, NY 10031
- PhD Program in Biochemistry, CUNY Graduate Center, New York, NY 10016
| | - Rinat R. Abzalimov
- Structural Biology Initiative, CUNY Advanced Science Research Center, New York, NY 10031
| | - Daniel A. Keedy
- Structural Biology Initiative, CUNY Advanced Science Research Center, New York, NY 10031
- Department of Chemistry and Biochemistry, City College of New York, New York, NY 10031
- PhD Programs in Biochemistry, Biology, & Chemistry, CUNY Graduate Center, New York, NY 10016
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5
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Maccari R, Ottanà R. Can Allostery Be a Key Strategy for Targeting PTP1B in Drug Discovery? A Lesson from Trodusquemine. Int J Mol Sci 2023; 24:ijms24119621. [PMID: 37298571 DOI: 10.3390/ijms24119621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 05/29/2023] [Accepted: 05/30/2023] [Indexed: 06/12/2023] Open
Abstract
Protein tyrosine phosphatase 1B (PTP1B) is an enzyme crucially implicated in aberrations of various signaling pathways that underlie the development of different human pathologies, such as obesity, diabetes, cancer, and neurodegenerative disorders. Its inhibition can prevent these pathogenetic events, thus providing a useful tool for the discovery of novel therapeutic agents. The search for allosteric PTP1B inhibitors can represent a successful strategy to identify drug-like candidates by offering the opportunity to overcome some issues related to catalytic site-directed inhibitors, which have so far hampered the development of drugs targeting this enzyme. In this context, trodusquemine (MSI-1436), a natural aminosterol that acts as a non-competitive PTP1B inhibitor, appears to be a milestone. Initially discovered as a broad-spectrum antimicrobial agent, trodusquemine exhibited a variety of unexpected properties, ranging from antidiabetic and anti-obesity activities to effects useful to counteract cancer and neurodegeneration, which prompted its evaluation in several preclinical and clinical studies. In this review article, we provide an overview of the main findings regarding the activities and therapeutic potential of trodusquemine and their correlation with PTP1B inhibition. We also included some aminosterol analogues and related structure-activity relationships that could be useful for further studies aimed at the discovery of new allosteric PTP1B inhibitors.
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Affiliation(s)
- Rosanna Maccari
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Viale F. Stagno d'Alcontres 31, 98166 Messina, Italy
| | - Rosaria Ottanà
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Viale F. Stagno d'Alcontres 31, 98166 Messina, Italy
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6
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Govindaraj RG, Thangapandian S, Schauperl M, Denny RA, Diller DJ. Recent applications of computational methods to allosteric drug discovery. Front Mol Biosci 2023; 9:1070328. [PMID: 36710877 PMCID: PMC9877542 DOI: 10.3389/fmolb.2022.1070328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Accepted: 12/13/2022] [Indexed: 01/13/2023] Open
Abstract
Interest in exploiting allosteric sites for the development of new therapeutics has grown considerably over the last two decades. The chief driving force behind the interest in allostery for drug discovery stems from the fact that in comparison to orthosteric sites, allosteric sites are less conserved across a protein family, thereby offering greater opportunity for selectivity and ultimately tolerability. While there is significant overlap between structure-based drug design for orthosteric and allosteric sites, allosteric sites offer additional challenges mostly involving the need to better understand protein flexibility and its relationship to protein function. Here we examine the extent to which structure-based drug design is impacting allosteric drug design by highlighting several targets across a variety of target classes.
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Affiliation(s)
- Rajiv Gandhi Govindaraj
- Computational Chemistry, HotSpot Therapeutics Inc., Boston, MA, United States,*Correspondence: Rajiv Gandhi Govindaraj,
| | | | - Michael Schauperl
- Computational Chemistry, HotSpot Therapeutics Inc., Boston, MA, United States
| | | | - David J. Diller
- Computational Chemistry, HotSpot Therapeutics Inc., Boston, MA, United States
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7
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Sharma S, Ebrahim A, Keedy DA. Room-temperature serial synchrotron crystallography of the human phosphatase PTP1B. Acta Crystallogr F Struct Biol Commun 2023; 79:23-30. [PMID: 36598353 PMCID: PMC9813971 DOI: 10.1107/s2053230x22011645] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 12/04/2022] [Indexed: 12/24/2022] Open
Abstract
Room-temperature X-ray crystallography provides unique insights into protein conformational heterogeneity, but obtaining sufficiently large protein crystals is a common hurdle. Serial synchrotron crystallography (SSX) helps to address this hurdle by allowing the use of many medium- to small-sized crystals. Here, a recently introduced serial sample-support chip system has been used to obtain the first SSX structure of a human phosphatase, specifically protein tyrosine phosphatase 1B (PTP1B) in the unliganded (apo) state. In previous apo room-temperature structures, the active site and allosteric sites adopted alternate conformations, including open and closed conformations of the active-site WPD loop and of a distal allosteric site. By contrast, in our SSX structure the active site is best fitted with a single conformation, but the distal allosteric site is best fitted with alternate conformations. This observation argues for additional nuance in interpreting the nature of allosteric coupling in this protein. Overall, our results illustrate the promise of serial methods for room-temperature crystallography, as well as future avant-garde crystallography experiments, for PTP1B and other proteins.
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Affiliation(s)
- Shivani Sharma
- Structural Biology Initiative, CUNY Advanced Science Research Center, New York, NY 10031, USA,PhD Program in Biology, CUNY Graduate Center, New York, NY 10016, USA
| | - Ali Ebrahim
- Structural Biology Initiative, CUNY Advanced Science Research Center, New York, NY 10031, USA
| | - Daniel A. Keedy
- Structural Biology Initiative, CUNY Advanced Science Research Center, New York, NY 10031, USA,Department of Chemistry and Biochemistry, City College of New York, New York, NY 10031, USA,PhD Programs in Biochemistry, Biology and Chemistry, CUNY Graduate Center, New York, NY 10016, USA,Correspondence e-mail:
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8
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Liu R, Mathieu C, Berthelet J, Zhang W, Dupret JM, Rodrigues Lima F. Human Protein Tyrosine Phosphatase 1B (PTP1B): From Structure to Clinical Inhibitor Perspectives. Int J Mol Sci 2022; 23:ijms23137027. [PMID: 35806030 PMCID: PMC9266911 DOI: 10.3390/ijms23137027] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 06/20/2022] [Accepted: 06/22/2022] [Indexed: 01/27/2023] Open
Abstract
Phosphorylation is an essential process in biological events and is considered critical for biological functions. In tissues, protein phosphorylation mainly occurs on tyrosine (Tyr), serine (Ser) and threonine (Thr) residues. The balance between phosphorylation and dephosphorylation is under the control of two super enzyme families, protein kinases (PKs) and protein phosphatases (PPs), respectively. Although there are many selective and effective drugs targeting phosphokinases, developing drugs targeting phosphatases is challenging. PTP1B, one of the most central protein tyrosine phosphatases (PTPs), is a key player in several human diseases and disorders, such as diabetes, obesity, and hematopoietic malignancies, through modulation of different signaling pathways. However, due to high conservation among PTPs, most PTP1B inhibitors lack specificity, raising the need to develop new strategies targeting this enzyme. In this mini-review, we summarize three classes of PTP1B inhibitors with different mechanisms: (1) targeting multiple aryl-phosphorylation sites including the catalytic site of PTP1B; (2) targeting allosteric sites of PTP1B; (3) targeting specific mRNA sequence of PTP1B. All three types of PTP1B inhibitors present good specificity over other PTPs and are promising for the development of efficient small molecules targeting this enzyme.
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Affiliation(s)
- Rongxing Liu
- Unité de Biologie Fonctionnelle et Adaptative, CNRS, Université Paris Cité, F-75013 Paris, France; (R.L.); (J.B.); (W.Z.); (J.-M.D.)
| | | | - Jérémy Berthelet
- Unité de Biologie Fonctionnelle et Adaptative, CNRS, Université Paris Cité, F-75013 Paris, France; (R.L.); (J.B.); (W.Z.); (J.-M.D.)
- Centre Epigénétique et Destin Cellulaire, Université Paris Cité, CNRS, F-75013 Paris, France
| | - Wenchao Zhang
- Unité de Biologie Fonctionnelle et Adaptative, CNRS, Université Paris Cité, F-75013 Paris, France; (R.L.); (J.B.); (W.Z.); (J.-M.D.)
- Department of Lymphoma and Myeloma, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
- Department of Genomic Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Jean-Marie Dupret
- Unité de Biologie Fonctionnelle et Adaptative, CNRS, Université Paris Cité, F-75013 Paris, France; (R.L.); (J.B.); (W.Z.); (J.-M.D.)
| | - Fernando Rodrigues Lima
- Unité de Biologie Fonctionnelle et Adaptative, CNRS, Université Paris Cité, F-75013 Paris, France; (R.L.); (J.B.); (W.Z.); (J.-M.D.)
- Correspondence:
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9
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Singh JP, Lin MJ, Hsu SF, Peti W, Lee CC, Meng TC. Crystal Structure of TCPTP Unravels an Allosteric Regulatory Role of Helix α7 in Phosphatase Activity. Biochemistry 2021; 60:3856-3867. [PMID: 34910875 DOI: 10.1021/acs.biochem.1c00519] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The T-cell protein tyrosine phosphatase (TCPTP/PTPN2) targets a broad variety of substrates across different subcellular compartments. In spite of that, the structural basis for the regulation of TCPTP's activity remains elusive. Here, we investigated whether the activity of TCPTP is regulated by a potential allosteric site in a comparable manner to its most similar PTP family member (PTP1B/PTPN1). We determined two crystal structures of TCPTP at 1.7 and 1.9 Å resolutions that include helix α7 at the TCPTP C-terminus. Helix α7 has been functionally characterized in PTP1B and was identified as its allosteric switch. However, its function is unknown in TCPTP. Here, we demonstrate that truncation or deletion of helix α7 reduced the catalytic efficiency of TCPTP by ∼4-fold. Collectively, our data supports an allosteric role of helix α7 in regulation of TCPTP's activity, similar to its function in PTP1B, and highlights that the coordination of helix α7 with the core catalytic domain is essential for the efficient catalytic function of TCPTP.
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Affiliation(s)
- Jai Prakash Singh
- Institute of Biological Chemistry, Academia Sinica, 128, Academia Road Sec. 2, Nankang, Taipei 115, Taiwan.,Chemical Biology and Molecular Biophysics, Taiwan International Graduate Program, Academia Sinica, 128, Academia Road Sec. 2, Nankang, Taipei 115, Taiwan.,Department of Chemistry, National Tsing Hua University, 101, Kuang-Fu Road, Sec. 2, Hsinchu 300, Taiwan
| | - Meng-Jung Lin
- Institute of Biological Chemistry, Academia Sinica, 128, Academia Road Sec. 2, Nankang, Taipei 115, Taiwan
| | - Shu-Fang Hsu
- Institute of Biological Chemistry, Academia Sinica, 128, Academia Road Sec. 2, Nankang, Taipei 115, Taiwan
| | - Wolfgang Peti
- Department of Molecular Biology and Biophysics, University of Connecticut Health Center, Farmington, Connecticut 06030, United States
| | - Cheng-Chung Lee
- Institute of Biological Chemistry, Academia Sinica, 128, Academia Road Sec. 2, Nankang, Taipei 115, Taiwan
| | - Tzu-Ching Meng
- Institute of Biological Chemistry, Academia Sinica, 128, Academia Road Sec. 2, Nankang, Taipei 115, Taiwan.,Chemical Biology and Molecular Biophysics, Taiwan International Graduate Program, Academia Sinica, 128, Academia Road Sec. 2, Nankang, Taipei 115, Taiwan.,Institute of Biochemical Sciences, National Taiwan University, 1 Roosevelt Road Sec. 4, Taipei 106, Taiwan
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10
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Elhassan RM, Hou X, Fang H. Recent advances in the development of allosteric protein tyrosine phosphatase inhibitors for drug discovery. Med Res Rev 2021; 42:1064-1110. [PMID: 34791703 DOI: 10.1002/med.21871] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 09/26/2021] [Accepted: 10/24/2021] [Indexed: 01/07/2023]
Abstract
Protein tyrosine phosphatases (PTPs) superfamily catalyzes tyrosine de-phosphorylation which affects a myriad of cellular processes. Imbalance in signal pathways mediated by PTPs has been associated with development of many human diseases including cancer, metabolic, and immunological diseases. Several compelling evidence suggest that many members of PTP family are novel therapeutic targets. However, the clinical development of conventional PTP-based active-site inhibitors originally was hampered by the poor selectivity and pharmacokinetic properties. In this regard, PTPs has been widely dismissed as "undruggable." Nonetheless, allosteric modulation has become increasingly an influential and alternative approach that can be exploited for drug development against PTPs. Unlike active-site inhibitors, allosteric inhibitors exhibit a remarkable target-selectivity, drug-likeness, potency, and in vivo activity. Intriguingly, there has been a high interest in novel allosteric PTPs inhibitors within the last years. In this review, we focus on the recent advances of allosteric inhibitors that have been explored in drug discovery and have shown an excellent result in the development of PTPs-based therapeutics. A special emphasis is placed on the structure-activity relationship and molecular mechanistic studies illustrating applications in chemical biology and medicinal chemistry.
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Affiliation(s)
- Reham M Elhassan
- Department of Medicinal Chemistry and Key Laboratory of Chemical Biology of Natural Products (MOE), School of Pharmacy, Shandong University, Jinan, Shandong, China
| | - Xuben Hou
- Department of Medicinal Chemistry and Key Laboratory of Chemical Biology of Natural Products (MOE), School of Pharmacy, Shandong University, Jinan, Shandong, China
| | - Hao Fang
- Department of Medicinal Chemistry and Key Laboratory of Chemical Biology of Natural Products (MOE), School of Pharmacy, Shandong University, Jinan, Shandong, China
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11
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Javier GM. Computational insight into the selective allosteric inhibition for PTP1B versus TCPTP: a molecular modelling study. J Biomol Struct Dyn 2020; 39:5399-5410. [PMID: 32643532 DOI: 10.1080/07391102.2020.1790421] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
All over the world, diabetes mellitus type 2 has spread as a problematic pandemic. Despite currently available treatments, approved drugs still show undesirable side effects and loss of efficacy or target symptoms instead of causes. Protein tyrosine phosphatase 1B (PTP1B), since its discovery, has emerged as a very promising target against this disease. Although the information regarding the enzyme is immense, little is known about the selectivity between this enzyme and its closest homologue, lymphocyte T tyrosine phosphatase (TCPTP), which is responsible for complicated side effects. In this study, on the basis of different computational approaches, we are able to highlight the importance of a phenylalanine residue located in PTP1B, but not in TCPTP, as a crucial hotspot that causes selectivity and stability for the whole ligand bound system. These results not only allow to explain the selectivity determinants of PTP1B but also provide a useful guide for the design of new allosteric inhibitors. Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Garcia-Marin Javier
- Facultad de Farmacia, Departamento de Química Orgánica y Química Inorgánica, Universidad de Alcalá, Alcalá de Henares, Spain.,Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain.,Facultad de Farmacia, Instituto de Investigación Química Andrés M. del Río, Universidad de Alcalá, Alcalá de Henares, Spain
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12
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SarathKumar B, Lakshmi BS. In silico investigations on the binding efficacy and allosteric mechanism of six different natural product compounds towards PTP1B inhibition through docking and molecular dynamics simulations. J Mol Model 2019; 25:272. [PMID: 31451955 DOI: 10.1007/s00894-019-4172-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Accepted: 08/16/2019] [Indexed: 01/07/2023]
Abstract
Protein tyrosine phosphatase 1B (PTP1B) is a major negative regulator of both the insulin and leptin receptor phosphorylation which impacts insulin sensitivity and hence is a major therapeutic target for the treatment of type 2 diabetes and obesity. Identification of PTP1B active site inhibitors has proven to be difficult with none of them clearing the phase II clinical trials. Since the conventional methods of targeting the active site of PTP1B have failed to bring out effective PTP1B inhibitors as potential drugs, recent studies are focussing on identification of potential allosteric inhibitors of PTP1B with better specificity and activity. A complete understanding of the molecular features dynamically involved for allosteric site inhibition is still uncertain, and hence, this study is aimed at evaluating the allosteric effectiveness of six natural compounds isolated from medicinal plants which showed in vitro antidiabetic activity along with PTP1B inhibition. The allosteric binding and inhibition of these compounds are studied using computational methods such as molecular docking, homology modelling and molecular dynamics simulations for a timescale of 100 ns. The molecular dynamics simulations of native PTP1B, along with the modelled allosteric α-7 helix, for a timescale of 100 ns, revealed the spontaneous transition of the native PTP1B from open WPD loop (active) to closed WPD loop (inactive) conformations during the simulations. Similar dynamics was observed in the presence of the active site substrate pTyr (phosphotyrosine), whereas this transition was inhibited in the presence of the compounds at the allosteric site. Results of molecular dynamics simulations and principal component analysis reveal that the hindrance to WPD loop was mediated through structural interactions between the allosteric α-helical triad with Loop11 and WPD loop. The MM-PBSA (Molecular Mechanics - Poisson Boltzmann with Surface Area solvation) binding energy results along with H-bonding analysis show the possible allosteric inhibition of Aloe emodin glycoside (AEG), 3β-taraxerol (3BT), chlorogenic acid (CGA) and cichoric acid (CHA) to be higher in comparison with (3β)-stigmast-5-en-3-ol (SGS) and methyl lignocerate (MLG). The interaction analysis was further validated by scoring the allosteric complexes before and after MD simulations using Glide. These findings on spontaneous PTP1B fluctuations and the allosteric interactions provide a better insight into the role of PTP1B fluctuations in impacting the binding energy of allosteric inhibitors towards optimal drug designing for PTP1B. Graphical abstract.
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Affiliation(s)
- Baskaran SarathKumar
- Department of Biotechnology, Anna University, Chennai, Tamil Nadu, 600 025, India
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13
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Shinde RN, Kumar GS, Eqbal S, Sobhia ME. Screening and identification of potential PTP1B allosteric inhibitors using in silico and in vitro approaches. PLoS One 2018; 13:e0199020. [PMID: 29912965 PMCID: PMC6005499 DOI: 10.1371/journal.pone.0199020] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Accepted: 04/12/2018] [Indexed: 12/25/2022] Open
Abstract
Protein tyrosine phosphatase 1B (PTP1B) is a validated therapeutic target for Type 2 diabetes due to its specific role as a negative regulator of insulin signaling pathways. Discovery of active site directed PTP1B inhibitors is very challenging due to highly conserved nature of the active site and multiple charge requirements of the ligands, which makes them non-selective and non-permeable. Identification of the PTP1B allosteric site has opened up new avenues for discovering potent and selective ligands for therapeutic intervention. Interactions made by potent allosteric inhibitor in the presence of PTP1B were studied using Molecular Dynamics (MD). Computationally optimized models were used to build separate pharmacophore models of PTP1B and TCPTP, respectively. Based on the nature of interactions the target residues offered, a receptor based pharmacophore was developed. The pharmacophore considering conformational flexibility of the residues was used for the development of pharmacophore hypothesis to identify potentially active inhibitors by screening large compound databases. Two pharmacophore were successively used in the virtual screening protocol to identify potential selective and permeable inhibitors of PTP1B. Allosteric inhibition mechanism of these molecules was established using molecular docking and MD methods. The geometrical criteria values confirmed their ability to stabilize PTP1B in an open conformation. 23 molecules that were identified as potential inhibitors were screened for PTP1B inhibitory activity. After screening, 10 molecules which have good permeability values were identified as potential inhibitors of PTP1B. This study confirms that selective and permeable inhibitors can be identified by targeting allosteric site of PTP1B.
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Affiliation(s)
- Ranajit Nivrutti Shinde
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research, S.A.S. Nagar, Punjab, India
| | - G. Siva Kumar
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research, S.A.S. Nagar, Punjab, India
| | - Shahbaz Eqbal
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research, S.A.S. Nagar, Punjab, India
| | - M. Elizabeth Sobhia
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research, S.A.S. Nagar, Punjab, India
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14
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Kumar AP, Nguyen MN, Verma C, Lukman S. Structural analysis of protein tyrosine phosphatase 1B reveals potentially druggable allosteric binding sites. Proteins 2018; 86:301-321. [PMID: 29235148 DOI: 10.1002/prot.25440] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 11/16/2017] [Accepted: 12/10/2017] [Indexed: 12/11/2022]
Abstract
Catalytic proteins such as human protein tyrosine phosphatase 1B (PTP1B), with conserved and highly polar active sites, warrant the discovery of druggable nonactive sites, such as allosteric sites, and potentially, therapeutic small molecules that can bind to these sites. Catalyzing the dephosphorylation of numerous substrates, PTP1B is physiologically important in intracellular signal transduction pathways in diverse cell types and tissues. Aberrant PTP1B is associated with obesity, diabetes, cancers, and neurodegenerative disorders. Utilizing clustering methods (based on root mean square deviation, principal component analysis, nonnegative matrix factorization, and independent component analysis), we have examined multiple PTP1B structures. Using the resulting representative structures in different conformational states, we determined consensus clustroids and used them to identify both known and novel binding sites, some of which are potentially allosteric. We report several lead compounds that could potentially bind to the novel PTP1B binding sites and can be further optimized. Considering the possibility for drug repurposing, we discovered homologous binding sites in other proteins, with ligands that could potentially bind to the novel PTP1B binding sites.
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Affiliation(s)
- Ammu Prasanna Kumar
- Department of Chemistry, College of Arts and Sciences, Khalifa University of Science and Technology, Abu Dhabi, United Arab Emirates
| | - Minh N Nguyen
- Bioinformatics Institute, Agency for Science, Technology and Research, Singapore
| | - Chandra Verma
- Bioinformatics Institute, Agency for Science, Technology and Research, Singapore.,Department of Biological Sciences, National University of Singapore, Singapore.,School of Biological Sciences, Nanyang Technological University, Singapore
| | - Suryani Lukman
- Department of Chemistry, College of Arts and Sciences, Khalifa University of Science and Technology, Abu Dhabi, United Arab Emirates
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15
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Zargari F, Lotfi M, Shahraki O, Nikfarjam Z, Shahraki J. Flavonoids as potent allosteric inhibitors of protein tyrosine phosphatase 1B: molecular dynamics simulation and free energy calculation. J Biomol Struct Dyn 2017; 36:4126-4142. [PMID: 29216799 DOI: 10.1080/07391102.2017.1409651] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Protein tyrosine phosphatase 1B (PTP1B) is a member of the PTP superfamily which is considered to be a negative regulator of insulin receptor (IR) signaling pathway. PTP1B is a promising drug target for the treatment of type 2 diabetes, obesity, and cancer. The existence of allosteric site in PTP1B has turned the researcher's attention to an alternate strategy for inhibition of this enzyme. Herein, the molecular interactions between the allosteric site of PTP1B with three non-competitive flavonoids, (MOR), (MOK), and (DPO) have been investigated. Three ligands were docked into allosteric site of the enzyme. The resulting protein-ligand complexes were used for molecular dynamics studies. Principal component and free-energy landscape (FEL) as well as cluster analyses were used to investigate the conformational and dynamical properties of the protein and identify representative enzyme substrates bounded to the inhibitors. Per residue energy decomposition analysis attributed dissimilar affinities of three inhibitors to the several hydrogen bonds and non-bonded interactions. In conclusion, our results exhibited an inhibitory pattern of the ligands against PTP1B.
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Affiliation(s)
- Farshid Zargari
- a Medicinal and Natural Products Chemistry Research Center , Shiraz University of Medical Sciences , Shiraz , Iran
| | - Maryam Lotfi
- b Testing Calibration, Geotechnic & Technical Inspection Servies , Binaazma Sepahan Consulting Eng. Co. , Isfahan , Iran
| | - Omolbanin Shahraki
- c Health Technology Incubator Center , Zahedan University of Medical Sciences , Zahedan , Iran
| | - Zahra Nikfarjam
- d Department of Molecular and Supramolecular Modelling , Chemistry and Chemical Engineering Research Center of Iran , Tehran , Iran
| | - Jafar Shahraki
- e Department of Pharmacology and Toxicology, Faculty of Pharmacy , Zabol University of Medical Sciences , Zabol , Iran
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16
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Sorokoumov VN, Shpakov AO. Protein phosphotyrosine phosphatase 1B: Structure, function, role in the development of metabolic disorders and their correction by the enzyme inhibitors. J EVOL BIOCHEM PHYS+ 2017. [DOI: 10.1134/s0022093017040020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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17
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Choy MS, Li Y, Machado LESF, Kunze MBA, Connors CR, Wei X, Lindorff-Larsen K, Page R, Peti W. Conformational Rigidity and Protein Dynamics at Distinct Timescales Regulate PTP1B Activity and Allostery. Mol Cell 2017; 65:644-658.e5. [PMID: 28212750 DOI: 10.1016/j.molcel.2017.01.014] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Revised: 12/07/2016] [Accepted: 01/09/2017] [Indexed: 12/31/2022]
Abstract
Protein function originates from a cooperation of structural rigidity, dynamics at different timescales, and allostery. However, how these three pillars of protein function are integrated is still only poorly understood. Here we show how these pillars are connected in Protein Tyrosine Phosphatase 1B (PTP1B), a drug target for diabetes and cancer that catalyzes the dephosphorylation of numerous substrates in essential signaling pathways. By combining new experimental and computational data on WT-PTP1B and ≥10 PTP1B variants in multiple states, we discovered a fundamental and evolutionarily conserved CH/π switch that is critical for positioning the catalytically important WPD loop. Furthermore, our data show that PTP1B uses conformational and dynamic allostery to regulate its activity. This shows that both conformational rigidity and dynamics are essential for controlling protein activity. This connection between rigidity and dynamics at different timescales is likely a hallmark of all enzyme function.
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Affiliation(s)
- Meng S Choy
- Department of Molecular Pharmacology, Physiology and Biotechnology, Brown University, Providence, RI 02912, USA
| | - Yang Li
- Department of Molecular Pharmacology, Physiology and Biotechnology, Brown University, Providence, RI 02912, USA
| | - Luciana E S F Machado
- Department of Molecular Pharmacology, Physiology and Biotechnology, Brown University, Providence, RI 02912, USA
| | - Micha B A Kunze
- Department of Biology, University of Copenhagen, 2200 Copenhagen, Denmark, Brown University, Providence, RI 02912, USA
| | - Christopher R Connors
- Department of Molecular Pharmacology, Physiology and Biotechnology, Brown University, Providence, RI 02912, USA
| | - Xingyu Wei
- Department of Molecular Pharmacology, Physiology and Biotechnology, Brown University, Providence, RI 02912, USA
| | - Kresten Lindorff-Larsen
- Department of Biology, University of Copenhagen, 2200 Copenhagen, Denmark, Brown University, Providence, RI 02912, USA
| | - Rebecca Page
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI 02912, USA
| | - Wolfgang Peti
- Department of Molecular Pharmacology, Physiology and Biotechnology, Brown University, Providence, RI 02912, USA; Department of Chemistry, Brown University, Providence, RI 02912, USA.
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18
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Inhibitory potential of polyhydroxylated fullerenes against protein tyrosine phosphatase 1B. UKRAINIAN BIOCHEMICAL JOURNAL 2015; 87:24-31. [DOI: 10.15407/ubj87.04.024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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19
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Li S, Zhang J, Lu S, Huang W, Geng L, Shen Q, Zhang J. The mechanism of allosteric inhibition of protein tyrosine phosphatase 1B. PLoS One 2014; 9:e97668. [PMID: 24831294 PMCID: PMC4022711 DOI: 10.1371/journal.pone.0097668] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2014] [Accepted: 04/09/2014] [Indexed: 11/24/2022] Open
Abstract
As the prototypical member of the PTP family, protein tyrosine phosphatase 1B (PTP1B) is an attractive target for therapeutic interventions in type 2 diabetes. The extremely conserved catalytic site of PTP1B renders the design of selective PTP1B inhibitors intractable. Although discovered allosteric inhibitors containing a benzofuran sulfonamide scaffold offer fascinating opportunities to overcome selectivity issues, the allosteric inhibitory mechanism of PTP1B has remained elusive. Here, molecular dynamics (MD) simulations, coupled with a dynamic weighted community analysis, were performed to unveil the potential allosteric signal propagation pathway from the allosteric site to the catalytic site in PTP1B. This result revealed that the allosteric inhibitor compound-3 induces a conformational rearrangement in helix α7, disrupting the triangular interaction among helix α7, helix α3, and loop11. Helix α7 then produces a force, pulling helix α3 outward, and promotes Ser190 to interact with Tyr176. As a result, the deviation of Tyr176 abrogates the hydrophobic interactions with Trp179 and leads to the downward movement of the WPD loop, which forms an H-bond between Asp181 and Glu115. The formation of this H-bond constrains the WPD loop to its open conformation and thus inactivates PTP1B. The discovery of this allosteric mechanism provides an overall view of the regulation of PTP1B, which is an important insight for the design of potent allosteric PTP1B inhibitors.
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Affiliation(s)
- Shuai Li
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of the Chinese Ministry of Education, Shanghai JiaoTong University, School of Medicine (SJTU-SM), Shanghai, China
| | - Jingmiao Zhang
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of the Chinese Ministry of Education, Shanghai JiaoTong University, School of Medicine (SJTU-SM), Shanghai, China
| | - Shaoyong Lu
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of the Chinese Ministry of Education, Shanghai JiaoTong University, School of Medicine (SJTU-SM), Shanghai, China
| | - Wenkang Huang
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of the Chinese Ministry of Education, Shanghai JiaoTong University, School of Medicine (SJTU-SM), Shanghai, China
| | - Lv Geng
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of the Chinese Ministry of Education, Shanghai JiaoTong University, School of Medicine (SJTU-SM), Shanghai, China
| | - Qiancheng Shen
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of the Chinese Ministry of Education, Shanghai JiaoTong University, School of Medicine (SJTU-SM), Shanghai, China
| | - Jian Zhang
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of the Chinese Ministry of Education, Shanghai JiaoTong University, School of Medicine (SJTU-SM), Shanghai, China
- Medicinal Bioinformatics Center, Shanghai JiaoTong University, School of Medicine, Shanghai, China
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20
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Eren D, Alakent B. Frequency response of a protein to local conformational perturbations. PLoS Comput Biol 2013; 9:e1003238. [PMID: 24086121 PMCID: PMC3784495 DOI: 10.1371/journal.pcbi.1003238] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Accepted: 08/11/2013] [Indexed: 11/18/2022] Open
Abstract
Signals created by local perturbations are known to propagate long distances through proteins via backbone connectivity and nonbonded interactions. In the current study, signal propagation from the flexible ligand binding loop to the rest of Protein Tyrosine Phosphatase 1B (PTP1B) was investigated using frequency response techniques. Using restrained Targeted Molecular Dynamics (TMD) potential on WPD and R loops, PTP1B was driven between its crystal structure conformations at different frequencies. Propagation of the local perturbation signal was manifested via peaks at the fundamental frequency and upper harmonics of 1/f distributed spectral density of atomic variables, such as Cα atoms, dihedral angles, or polar interaction distances. Frequency of perturbation was adjusted high enough (simulation length >∼10×period of a perturbation cycle) not to be clouded by random diffusional fluctuations, and low enough (<∼0.8 ns(-1)) not to attenuate the propagating signal and enhance the contribution of the side-chains to the dissipation of the signals. Employing Discrete Fourier Transform (DFT) to TMD simulation trajectories of 16 cycles of conformational transitions at periods of 1.2 to 5 ns yielded Cα displacements consistent with those obtained from crystal structures. Identification of the perturbed atomic variables by statistical t-tests on log-log scale spectral densities revealed the extent of signal propagation in PTP1B, while phase angles of the filtered trajectories at the fundamental frequency were used to cluster collectively fluctuating elements. Hydrophobic interactions were found to have a higher contribution to signal transduction between side-chains compared to the role of polar interactions. Most of in-phase fluctuating residues on the signaling pathway were found to have high identity among PTP domains, and located over a wide region of PTP1B including the allosteric site. Due to its simplicity and efficiency, the suggested technique may find wide applications in identification of signaling pathways of different proteins.
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Affiliation(s)
- Dilek Eren
- Department of Chemical Engineering, Bogazici University, Bebek, Istanbul, Turkey
| | - Burak Alakent
- Department of Chemical Engineering, Bogazici University, Bebek, Istanbul, Turkey
- * E-mail:
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21
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Shinde RN, Sobhia ME. Binding and discerning interactions of PTP1B allosteric inhibitors: Novel insights from molecular dynamics simulations. J Mol Graph Model 2013; 45:98-110. [DOI: 10.1016/j.jmgm.2013.08.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Revised: 06/30/2013] [Accepted: 08/06/2013] [Indexed: 10/26/2022]
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22
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Ozcan A, Olmez EO, Alakent B. Effects of protonation state of Asp181 and position of active site water molecules on the conformation of PTP1B. Proteins 2013; 81:788-804. [PMID: 23239271 DOI: 10.1002/prot.24234] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Revised: 10/19/2012] [Accepted: 12/05/2012] [Indexed: 12/11/2022]
Abstract
In protein tyrosine phosphatase 1B (PTP1B), the flexible WPD loop adopts a closed conformation (WPDclosed ) in the active state of PTP1B, bringing the catalytic Asp181 close to the active site pocket, while WPD loop is in an open conformation (WPDopen ) in the inactive state. Previous studies showed that Asp181 may be protonated at physiological pH, and ordered water molecules exist in the active site. In the current study, molecular dynamics simulations are employed at different Asp181 protonation states and initial positions of active site water molecules, and compared with the existing crystallographic data of PTP1B. In WPDclosed conformation, the active site is found to maintain its conformation only in the protonated state of Asp181 in both free and liganded states, while Asp181 is likely to be deprotonated in WPDopen conformation. When the active site water molecule network that is a part of the free WPDclosed crystal structure is disrupted, intermediate WPD loop conformations, similar to that in the PTPRR crystal structure, are sampled in the MD simulations. In liganded PTP1B, one active site water molecule is found to be important for facilitating the orientation of Cys215 and the phosphate ion, thus may play a role in the reaction. In conclusion, conformational stability of WPD loop, and possibly catalytic activity of PTP1B, is significantly affected by the protonation state of Asp181 and position of active site water molecules, showing that these aspects should be taken into consideration both in MD simulations and inhibitor design.
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Affiliation(s)
- Ahmet Ozcan
- Graduate Program in Computational Science and Engineering, Bogazici University, Bebek, Istanbul 34342, Turkey
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23
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Baskaran SK, Goswami N, Selvaraj S, Muthusamy VS, Lakshmi BS. Molecular Dynamics Approach to Probe the Allosteric Inhibition of PTP1B by Chlorogenic and Cichoric Acid. J Chem Inf Model 2012; 52:2004-12. [DOI: 10.1021/ci200581g] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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24
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Wang ZJ, Si YX, Oh S, Yang JM, Yin SJ, Park YD, Lee J, Qian GY. The effect of fucoidan on tyrosinase: computational molecular dynamics integrating inhibition kinetics. J Biomol Struct Dyn 2012; 30:460-73. [PMID: 22694253 DOI: 10.1080/07391102.2012.682211] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Fucoidan is a complex sulfated polysaccharide extracted from brown seaweed and has a wide variety of biological activities. In this study, we investigated the inhibitory effect of fucoidan on tyrosinase via a combination of inhibition kinetics and computational simulations. Fucoidan reversibly inhibited tyrosinase in a mixed-type manner. Time-interval kinetics showed that the inhibition was processed as first order with biphasic processes. For further insight, we simulated dockings with various sizes of molecular models (monomer to decamer) of fucoidan and showed that the best binding energy change results were obtained from the pentamer (-1.89 kcal/mol) and the hexamer (-1.97 kcal/mol) models of AutoDock Vina. The molecular dynamics simulation confirmed the binding mechanisms between tyrosinase and fucoidan and suggested that fucoidan mostly interacts with several residues including copper ions located in the active site. Our study suggests that fucoidan might be a potential natural antipigment agent.
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Affiliation(s)
- Zhi-Jiang Wang
- College of Biological and Environmental Sciences, Zhejiang Wanli University, Ningbo, 315100, P.R. China
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25
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Majumder R, Roy S, Thakur AR. Analysis of Delta–Notch interaction by molecular modeling and molecular dynamic simulation studies. J Biomol Struct Dyn 2012; 30:13-29. [DOI: 10.1080/07391102.2012.674184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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26
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Jardin C, Sticht H. Identification of the Structural Features that Mediate Binding Specificity in the Recognition of STAT Proteins by Dual-Specificity Phosphatases. J Biomol Struct Dyn 2012; 29:777-92. [DOI: 10.1080/07391102.2012.10507413] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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27
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Hamza A, Wei NN, Johnson-Scalise T, Naftolin F, Cho H, Zhan CG. Unveiling the Unfolding Pathway of F5F8D Disorder-Associated D81H/V100D Mutant of MCFD2viaMultiple Molecular Dynamics Simulations. J Biomol Struct Dyn 2012; 29:699-714. [DOI: 10.1080/07391102.2012.10507410] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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28
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Ramakrishnan V, Jagannathan S, Shaikh AR, Rajagopalan R. Dynamic and Structural Changes in the Minimally Restructuring EcoRI Bound to a Minimally Mutated DNA Chain. J Biomol Struct Dyn 2012; 29:743-56. [DOI: 10.1080/073911012010525020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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