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Wu L, Sadhukhan A, Kobayashi Y, Ogo N, Tokizawa M, Agrahari RK, Ito H, Iuchi S, Kobayashi M, Asai A, Koyama H. Involvement of phosphatidylinositol metabolism in aluminum-induced malate secretion in Arabidopsis. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:3329-3342. [PMID: 30977815 DOI: 10.1093/jxb/erz179] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 04/03/2019] [Indexed: 05/27/2023]
Abstract
To identify the upstream signaling of aluminum-induced malate secretion through aluminum-activated malate transporter 1 (AtALMT1), a pharmacological assay using inhibitors of human signal transduction pathways was performed. Early aluminum-induced transcription of AtALMT1 and other aluminum-responsive genes was significantly suppressed by phosphatidylinositol 4-kinase (PI4K) and phospholipase C (PLC) inhibitors, indicating that the PI4K-PLC metabolic pathway activates early aluminum signaling. Inhibitors of phosphatidylinositol 3-kinase (PI3K) and PI4K reduced aluminum-activated malate transport by AtALMT1, suggesting that both the PI3K and PI4K metabolic pathways regulate this process. These results were validated using T-DNA insertion mutants of PI4K and PI3K-RNAi lines. A human protein kinase inhibitor, putatively inhibiting homologous calcineurin B-like protein-interacting protein kinase and/or Ca-dependent protein kinase in Arabidopsis, suppressed late-phase aluminum-induced expression of AtALMT1, which was concomitant with the induction of an AtALMT1 repressor, WRKY46, and suppression of an AtALMT1 activator, Calmodulin-binding transcription activator 2 (CAMTA2). In addition, a human deubiquitinase inhibitor suppressed aluminum-activated malate transport, suggesting that deubiquitinases can regulate this process. We also found a reduction of aluminum-induced citrate secretion in tobacco by applying inhibitors of PI3K and PI4K. Taken together, our results indicated that phosphatidylinositol metabolism regulates organic acid secretion in plants under aluminum stress.
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Affiliation(s)
- Liujie Wu
- Applied Biological Sciences, Gifu University, Gifu, Japan
| | - Ayan Sadhukhan
- Applied Biological Sciences, Gifu University, Gifu, Japan
| | | | - Naohisa Ogo
- Graduate Division of Pharmaceutical Sciences, University of Shizuoka, Shizuoka, Japan
| | | | | | - Hiroki Ito
- Applied Biological Sciences, Gifu University, Gifu, Japan
| | - Satoshi Iuchi
- Experimental Plant Division, RIKEN BioResource Research Center, Tsukuba, Ibaraki, Japan
| | - Masatomo Kobayashi
- Experimental Plant Division, RIKEN BioResource Research Center, Tsukuba, Ibaraki, Japan
| | - Akira Asai
- Graduate Division of Pharmaceutical Sciences, University of Shizuoka, Shizuoka, Japan
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Masson GR, Burke JE, Ahn NG, Anand GS, Borchers C, Brier S, Bou-Assaf GM, Engen JR, Englander SW, Faber J, Garlish R, Griffin PR, Gross ML, Guttman M, Hamuro Y, Heck AJR, Houde D, Iacob RE, Jørgensen TJD, Kaltashov IA, Klinman JP, Konermann L, Man P, Mayne L, Pascal BD, Reichmann D, Skehel M, Snijder J, Strutzenberg TS, Underbakke ES, Wagner C, Wales TE, Walters BT, Weis DD, Wilson DJ, Wintrode PL, Zhang Z, Zheng J, Schriemer DC, Rand KD. Recommendations for performing, interpreting and reporting hydrogen deuterium exchange mass spectrometry (HDX-MS) experiments. Nat Methods 2019; 16:595-602. [PMID: 31249422 PMCID: PMC6614034 DOI: 10.1038/s41592-019-0459-y] [Citation(s) in RCA: 478] [Impact Index Per Article: 79.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 05/23/2019] [Indexed: 12/20/2022]
Abstract
Hydrogen deuterium exchange mass spectrometry (HDX-MS) is a powerful biophysical technique being increasingly applied to a wide variety of problems. As the HDX-MS community continues to grow, adoption of best practices in data collection, analysis, presentation and interpretation will greatly enhance the accessibility of this technique to nonspecialists. Here we provide recommendations arising from community discussions emerging out of the first International Conference on Hydrogen-Exchange Mass Spectrometry (IC-HDX; 2017). It is meant to represent both a consensus viewpoint and an opportunity to stimulate further additions and refinements as the field advances.
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Affiliation(s)
| | - John E Burke
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada.
| | - Natalie G Ahn
- Department of Biochemistry, University of Colorado, Boulder, CO, USA
| | - Ganesh S Anand
- Department of Biological Science, National University of Singapore, Singapore, Singapore
| | - Christoph Borchers
- Genome BC Proteomics Centre, University of Victoria, Victoria, BC, Canada
| | - Sébastien Brier
- Institut Pasteur, Chemistry and Structural Biology Department, Paris, France
| | | | - John R Engen
- Department of Chemistry and Chemical Biology, Northeastern University, Boston, MA, USA
| | - S Walter Englander
- Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, PA, USA
| | | | | | - Patrick R Griffin
- Department of Integrative Structural and Computational Biology, Scripps Florida, The Scripps Research Institute, Jupiter, FL, USA
| | - Michael L Gross
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO, USA
| | - Miklos Guttman
- Department of Medicinal Chemistry, School of Pharmacy, University of Washington, Seattle, WA, USA
| | - Yoshitomo Hamuro
- Johnson & Johnson Pharmaeutical Research and Development, Jersey City, NJ, USA
| | - Albert J R Heck
- Bijvoet Center for Biomolecular Research, Utrecht University, Utrecht, the Netherlands
| | | | - Roxana E Iacob
- Department of Chemistry and Chemical Biology, Northeastern University, Boston, MA, USA
| | - Thomas J D Jørgensen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej, Odense, Denmark
| | - Igor A Kaltashov
- Department of Chemistry, University of Massachusetts-Amherst, Amherst, MA, USA
| | - Judith P Klinman
- Department of Chemistry, University of California, Berkeley, Berkeley, CA, USA
| | - Lars Konermann
- Department of Chemistry, The University of Western Ontario, London, ON, Canada
| | - Petr Man
- Institute of Microbiology, Czech Academy of Sciences, Prague, Czech Republic
| | - Leland Mayne
- Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, PA, USA
| | - Bruce D Pascal
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL, USA
| | - Dana Reichmann
- Department of Biological Chemistry, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Mark Skehel
- MRC Laboratory of Molecular Biology, Cambridge, UK
| | - Joost Snijder
- Department of Medicinal Chemistry, School of Pharmacy, University of Washington, Seattle, WA, USA
| | - Timothy S Strutzenberg
- Department of Integrative Structural and Computational Biology, Scripps Florida, The Scripps Research Institute, Jupiter, FL, USA
| | - Eric S Underbakke
- Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, IA, USA
| | | | - Thomas E Wales
- Department of Chemistry and Chemical Biology, Northeastern University, Boston, MA, USA
| | - Benjamin T Walters
- Department of Early Stage Pharmaceutical Development, Genentech, Inc., South San Francisco, CA, USA
| | - David D Weis
- Department of Pharmaceutical Chemistry, University of Kansas, Lawrence, KS, USA
| | - Derek J Wilson
- Department of Chemistry, York University, Toronto, ON, Canada
| | - Patrick L Wintrode
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, MD, USA
| | | | - Jie Zheng
- Department of Integrative Structural and Computational Biology, Scripps Florida, The Scripps Research Institute, Jupiter, FL, USA
| | - David C Schriemer
- Department of Biochemistry & Molecular Biology, University of Calgary, Calgary, AB, Canada.
| | - Kasper D Rand
- Department of Pharmacy, University of Copenhagen, Copenhagen, Denmark.
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Arita M. Essential domains of phosphatidylinositol-4 kinase III β required for enterovirus replication. Microbiol Immunol 2019; 63:285-288. [PMID: 31166044 DOI: 10.1111/1348-0421.12718] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Revised: 05/30/2019] [Accepted: 06/02/2019] [Indexed: 12/23/2022]
Abstract
Phosphatidylinositol-4 kinase III β (PI4KB) is a host factor that is required for enterovirus (EV) replication. In this study, the importance of host proteins that interact with PI4KB in EV replication was analyzed by trans complementation with PI4KB mutants in a PI4KB-knockout cell line. Ectopically expressed PI4KB mutants, which lack binding regions for ACBD3, RAB11, and 14-3-3 proteins, rescued replication of poliovirus and enterovirus 71. These findings suggest that interaction of PI4KB with these host proteins is not essential for EV replication once PI4KB has been expressed and that PI4KB is functionally independent from these host proteins regarding EV replication.
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Affiliation(s)
- Minetaro Arita
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan
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Nakada-Tsukui K, Watanabe N, Maehama T, Nozaki T. Phosphatidylinositol Kinases and Phosphatases in Entamoeba histolytica. Front Cell Infect Microbiol 2019; 9:150. [PMID: 31245297 PMCID: PMC6563779 DOI: 10.3389/fcimb.2019.00150] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2018] [Accepted: 04/23/2019] [Indexed: 12/11/2022] Open
Abstract
Phosphatidylinositol (PtdIns) metabolism is indispensable in eukaryotes. Phosphoinositides (PIs) are phosphorylated derivatives of PtdIns and consist of seven species generated by reversible phosphorylation of the inositol moieties at the positions 3, 4, and 5. Each of the seven PIs has a unique subcellular and membrane domain distribution. In the enteric protozoan parasite Entamoeba histolytica, it has been previously shown that the PIs phosphatidylinositol 3-phosphate (PtdIns3P), PtdIns(4,5)P2, and PtdIns(3,4,5)P3 are localized to phagosomes/phagocytic cups, plasma membrane, and phagocytic cups, respectively. The localization of these PIs in E. histolytica is similar to that in mammalian cells, suggesting that PIs have orthologous functions in E. histolytica. In contrast, the conservation of the enzymes that metabolize PIs in this organism has not been well-documented. In this review, we summarized the full repertoire of the PI kinases and PI phosphatases found in E. histolytica via a genome-wide survey of the current genomic information. E. histolytica appears to have 10 PI kinases and 23 PI phosphatases. It has a panel of evolutionarily conserved enzymes that generate all the seven PI species. However, class II PI 3-kinases, type II PI 4-kinases, type III PI 5-phosphatases, and PI 4P-specific phosphatases are not present. Additionally, regulatory subunits of class I PI 3-kinases and type III PI 4-kinases have not been identified. Instead, homologs of class I PI 3-kinases and PTEN, a PI 3-phosphatase, exist as multiple isoforms, which likely reflects that elaborate signaling cascades mediated by PtdIns(3,4,5)P3 are present in this organism. There are several enzymes that have the nuclear localization signal: one phosphatidylinositol phosphate (PIP) kinase, two PI 3-phosphatases, and one PI 5-phosphatase; this suggests that PI metabolism also has conserved roles related to nuclear functions in E. histolytica, as it does in model organisms.
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Affiliation(s)
- Kumiko Nakada-Tsukui
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo, Japan
| | - Natsuki Watanabe
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo, Japan.,Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Japan
| | - Tomohiko Maehama
- Division of Molecular and Cellular Biology, Graduate School of Medicine, Kobe University, Kobe, Japan
| | - Tomoyoshi Nozaki
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
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55
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Ibrahim MAA, Abdelrahman AHM, Hassan AMA. Identification of novel Plasmodium falciparum PI4KB inhibitors as potential anti-malarial drugs: Homology modeling, molecular docking and molecular dynamics simulations. Comput Biol Chem 2019; 80:79-89. [PMID: 30928871 DOI: 10.1016/j.compbiolchem.2019.03.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Revised: 01/18/2019] [Accepted: 03/22/2019] [Indexed: 11/19/2022]
Abstract
The current study was set to discover selective Plasmodium falciparum phosphatidylinositol-4-OH kinase type III beta (pfPI4KB) inhibitors as potential antimalarial agents using combined structure-based and ligand-based drug discovery approach. A comparative model of pfPI4KB was first constructed and validated using molecular docking techniques. Performance of Autodock4.2 and Vina4 software in predicting the inhibitor-PI4KB binding mode and energy was assessed based on two Test Sets: Test Set I contained five ligands with resolved crystal structures with PI4KB, while Test Set II considered eleven compounds with known IC50 value towards PI4KB. The outperformance of Autodock as compared to Vina was reported, giving a correlation coefficient (R2) value of 0.87 and 0.90 for Test Set I and Test Set II, respectively. Pharmacophore-based screening was then conducted to identify drug-like molecules from ZINC database with physicochemical similarity to two potent pfPI4KB inhibitors -namely cpa and cpb. For each query inhibitor, the best 1000 hits in terms of TanimotoCombo scores were selected and subjected to molecular docking and molecular dynamics (MD) calculations. Binding energy was then estimated using molecular mechanics-generalized Born surface area (MM-GBSA) approach over 50 ns MD simulations of the inhibitor-pfPI4KB complexes. According to the calculated MM-GBSA binding energies, ZINC78988474 and ZINC20564116 were identified as potent pfPI4KB inhibitors with binding energies better than those of cpa and cpb, with ΔGbinding ≥ -34.56 kcal/mol. The inhibitor-pfPI4KB interaction and stability were examined over 50 ns MD simulation; as well the selectivity of the identified inhibitors towards pfPI4KB over PI4KB was reported.
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Affiliation(s)
- Mahmoud A A Ibrahim
- Computational Chemistry Laboratory, Chemistry Department, Faculty of Science, Minia University, Minia 61519, Egypt.
| | - Alaa H M Abdelrahman
- Computational Chemistry Laboratory, Chemistry Department, Faculty of Science, Minia University, Minia 61519, Egypt
| | - Alaa M A Hassan
- Computational Chemistry Laboratory, Chemistry Department, Faculty of Science, Minia University, Minia 61519, Egypt
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56
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Abstract
Since I started doing scientific research, I've been fascinated by the interplay of protein structure and dynamics and how they together mediate protein function. A particular area of interest has been in understanding the mechanistic basis of how lipid-signaling enzymes function on membrane surfaces. In this award lecture article, I will describe my laboratory's studies on the structure and dynamics of lipid-signaling enzymes on membrane surfaces. This is important, as many lipid-signaling enzymes are regulated through dynamic regulatory mechanisms that control their enzymatic activity. This article will discuss my continued enthusiasm in using a synergistic application of hydrogen-deuterium exchange MS (HDX-MS) with other structural biology techniques to probe the mechanistic basis for how membrane-localized signaling enzymes are regulated and how these approaches can be used to understand how they are misregulated in disease. I will discuss specific examples of how we have used HDX-MS to study phosphoinositide kinases and the protein kinase Akt. An important focus will be on a description of how HDX-MS can be used as a powerful tool to optimize the design of constructs for X-ray crystallography and EM. The use of a diverse toolbox of biophysical methods has revealed novel insight into the complex and varied regulatory networks that control the function of lipid-signaling enzymes and enabled unique insight into the mechanics of membrane recruitment.
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Affiliation(s)
- John E Burke
- From the Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8W 2Y2, Canada
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57
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Chalupska D, Różycki B, Humpolickova J, Faltova L, Klima M, Boura E. Phosphatidylinositol 4-kinase IIIβ (PI4KB) forms highly flexible heterocomplexes that include ACBD3, 14-3-3, and Rab11 proteins. Sci Rep 2019; 9:567. [PMID: 30679637 PMCID: PMC6345845 DOI: 10.1038/s41598-018-37158-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Accepted: 11/29/2018] [Indexed: 12/18/2022] Open
Abstract
Phosphatidylinositol 4-kinase IIIβ (PI4KB) is a key enzyme of the Golgi system because it produces its lipid hallmark - the phosphatidylinositol 4-phosphate (PI4P). It is recruited to Golgi by the Golgi resident ACBD3 protein, regulated by 14-3-3 proteins and it also serves as an adaptor because it recruits the small GTPase Rab11. Here, we analyzed the protein complexes formed by PI4KB in vitro using small angle x-ray scattering (SAXS) and we discovered that these protein complexes are highly flexible. The 14-3-3:PI4KB:Rab11 protein complex has 2:1:1 stoichiometry and its different conformations are rather compact, however, the ACBD3:PI4KB protein complex has both, very compact and very extended conformations. Furthermore, in vitro reconstitution revealed that the membrane is necessary for the formation of ACBD3:PI4KB:Rab11 protein complex at physiological (nanomolar) concentrations.
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Affiliation(s)
- Dominika Chalupska
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo nam. 2., Prague, Czech Republic
| | - Bartosz Różycki
- Institute of Physics, Polish Academy of Sciences, Al. Lotnikow 32/46, 02-668, Warsaw, Poland
| | - Jana Humpolickova
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo nam. 2., Prague, Czech Republic
| | - Lenka Faltova
- Laboratory of Biomolecular Research, Department of Biology and Chemistry, Paul Scherrer Institute, 5232, Villigen, PSI, Switzerland
| | - Martin Klima
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo nam. 2., Prague, Czech Republic
| | - Evzen Boura
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo nam. 2., Prague, Czech Republic.
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58
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Lin F, Krishnamoorthy P, Schubert V, Hause G, Heilmann M, Heilmann I. A dual role for cell plate-associated PI4Kβ in endocytosis and phragmoplast dynamics during plant somatic cytokinesis. EMBO J 2019; 38:embj.2018100303. [PMID: 30617084 DOI: 10.15252/embj.2018100303] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 11/29/2018] [Accepted: 12/04/2018] [Indexed: 11/09/2022] Open
Abstract
Plant cytokinesis involves membrane trafficking and cytoskeletal rearrangements. Here, we report that the phosphoinositide kinases PI4Kβ1 and PI4Kβ2 integrate these processes in Arabidopsis thaliana (Arabidopsis) roots. Cytokinetic defects of an Arabidopsis pi4kβ1 pi4kβ2 double mutant are accompanied by defects in membrane trafficking. Specifically, we show that trafficking of the proteins KNOLLE and PIN2 at the cell plate, clathrin recruitment, and endocytosis is impaired in pi4kβ1 pi4kβ2 double mutants, accompanied by unfused vesicles at the nascent cell plate and around cell wall stubs. Interestingly, pi4kβ1 pi4kβ2 plants also display ectopic overstabilization of phragmoplast microtubules, which guide membrane trafficking at the cell plate. The overstabilization of phragmoplasts in the double mutant coincides with mislocalization of the microtubule-associated protein 65-3 (MAP65-3), which cross-links microtubules and is a downstream target for inhibition by the MAP kinase MPK4. Based on similar cytokinetic defects of the pi4kβ1 pi4kβ2 and mpk4-2 mutants and genetic and physical interaction of PI4Kβ1 and MPK4, we propose that PI4Kβ and MPK4 influence localization and activity of MAP65-3, respectively, acting synergistically to control phragmoplast dynamics.
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Affiliation(s)
- Feng Lin
- Department of Cellular Biochemistry, Institute of Biochemistry and Biotechnology, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany
| | - Praveen Krishnamoorthy
- Department of Cellular Biochemistry, Institute of Biochemistry and Biotechnology, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany
| | - Veit Schubert
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, Seeland, Germany
| | - Gerd Hause
- Biocenter, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany
| | - Mareike Heilmann
- Department of Cellular Biochemistry, Institute of Biochemistry and Biotechnology, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany
| | - Ingo Heilmann
- Department of Cellular Biochemistry, Institute of Biochemistry and Biotechnology, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany
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Tian S, Zeng J, Liu X, Chen J, Zhang JZH, Zhu T. Understanding the selectivity of inhibitors toward PI4KIIIα and PI4KIIIβ based molecular modeling. Phys Chem Chem Phys 2019; 21:22103-22112. [DOI: 10.1039/c9cp03598b] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Molecular dynamics simulations and binding free energy calculations are combined to investigate the selectivity of inhibitors toward type III phosphatidylinositol 4 kinases.
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Affiliation(s)
- Shuaizhen Tian
- Shanghai Engineering Research Center of Molecular Therapeutics & New Drug Development
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai
- China
| | - Jinzhe Zeng
- Shanghai Engineering Research Center of Molecular Therapeutics & New Drug Development
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai
- China
| | - Xiao Liu
- School of Mathematics, Physics and Statistics
- Shanghai University of Engineering Science
- Shanghai 201620
- China
| | - Jianzhong Chen
- School of Science
- Shandong Jiaotong University
- Jinan 250357
- China
| | - John Z. H. Zhang
- Shanghai Engineering Research Center of Molecular Therapeutics & New Drug Development
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai
- China
| | - Tong Zhu
- Shanghai Engineering Research Center of Molecular Therapeutics & New Drug Development
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai
- China
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A Single Point Mutation in the Rhinovirus 2B Protein Reduces the Requirement for Phosphatidylinositol 4-Kinase Class III Beta in Viral Replication. J Virol 2018; 92:JVI.01462-18. [PMID: 30209171 DOI: 10.1128/jvi.01462-18] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Accepted: 08/31/2018] [Indexed: 01/31/2023] Open
Abstract
Rhinoviruses (RVs) replicate on cytoplasmic membranes derived from the Golgi apparatus. They encode membrane-targeted proteins 2B, 2C, and 3A, which control trafficking and lipid composition of the replication membrane. The virus recruits host factors for replication, such as phosphatidylinositol 4 (PI4)-kinase 3beta (PI4K3b), which boosts PI4-phosphate (PI4P) levels and drives lipid countercurrent exchange of PI4P against cholesterol at endoplasmic reticulum-Golgi membrane contact sites through the lipid shuttling protein oxysterol binding protein 1 (OSBP1). We identified a PI4K3b inhibitor-resistant RV-A16 variant with a single point mutation in the conserved 2B protein near the cytosolic carboxy terminus, isoleucine 92 to threonine (termed 2B[I92T]). The mutation did not confer resistance to cholesterol-sequestering compounds or OSBP1 inhibition, suggesting invariant dependency on the PI4P/cholesterol lipid countercurrents. In the presence of PI4K3b inhibitor, Golgi reorganization and PI4P lipid induction occurred in RV-A16 2B[I92] but not in wild-type infection. The knockout of PI4K3b abolished the replication of both the 2B[I92T] mutant and the wild type. Doxycycline-inducible expression of PI4K3b in PI4K3b knockout cells efficiently rescued the 2B[I92T] mutant and, less effectively, wild-type virus infection. Ectopic expression of 2B[I92T] or 2B was less efficient than that of 3A in recruiting PI4K3b to perinuclear membranes, suggesting a supportive rather than decisive role of 2B in recruiting PI4K3b. The data suggest that 2B tunes the recruitment of PI4K3b to the replication membrane and allows the virus to adapt to cells with low levels of PI4K3b while still maintaining the PI4P/cholesterol countercurrent for establishing Golgi-derived RV replication membranes.IMPORTANCE Human rhinoviruses (RVs) are the major cause of the common cold worldwide. They cause asthmatic exacerbations and chronic obstructive pulmonary disease. Despite recent advances, the development of antivirals and vaccines has proven difficult due to the high number and variability of RV types. The identification of critical host factors and their interactions with viral proteins and membrane lipids for the establishment of viral replication is a basis for drug development strategies. Our findings here shed new light on the interactions between nonstructural viral membrane proteins and class III phosphatidylinositol 4 kinases from the host and highlight the importance of phosphatidylinositol 4 phosphate for RV replication.
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Nakajima K, Nozawa T, Minowa-Nozawa A, Toh H, Yamada S, Aikawa C, Nakagawa I. RAB30 regulates PI4KB (phosphatidylinositol 4-kinase beta)-dependent autophagy against group A Streptococcus. Autophagy 2018; 15:466-477. [PMID: 30290718 DOI: 10.1080/15548627.2018.1532260] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
Abstract
Macroautophagy/autophagy plays an important role in the immune response to invasion by intracellular pathogens such as group A Streptococcus (GAS; Streptococcus pyogenes). We previously identified RAB30, a Golgi-resident GTPase, as a novel anti-bacterial autophagic regulator in the formation of GAS-containing autophagosome-like vacuoles (GcAVs); however, the precise mechanism underlying this process remains elusive. Here, we elucidate a novel property of RAB30: the ability to recruit PI4KB (phosphatidylinositol 4-kinase beta) to the Golgi apparatus and GcAVs. We found that trans-Golgi network (TGN) vesicles were incorporated into GcAVs via RAB30 to promote GcAV formation. Moreover, depletion of phosphatidylinositol-4-phosphate (PtdIns4P), a phosphatidylinositol enriched in the TGN, by wortmannin and phenylarsine oxide, followed by subsequent repletion with exogenous PtdIns4P revealed that PtdIns4P is crucial for GcAV formation. Furthermore, we identify an interaction between RAB30 and PI4KB, in which the knockdown of RAB30 decreased the localization of PI4KB to the TGN and GcAVs. Finally, PI4KB knockout suppressed autophagy by inhibiting GcAV formation, resulting in the increased survival of GAS. Our results demonstrate a novel autophagosomal formation mechanism involving coordinative functions of RAB30 and PI4KB distinct from those utilized in canonical autophagy. Abbreviations: GAS: group A Streptococcus; GcAVs: GAS-containing autophagosome-like vacuoles; PI4KB: phosphatidylinositol 4-kinase beta; PtdIns: phosphatidylinositol; PtdIns3P: phosphatidylinositol-3-phosphate; PtdIns4P: phosphatidylinositol-4-phosphate; PtdIns5P: phosphatidylinositol-5-phosphate; SLO: streptolysin O; TGN: trans-Golgi network; TGOLN2: trans-golgi network protein 2; PH: plekstrin homology; OSBP: oxysterol binding protein.
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Affiliation(s)
- Koji Nakajima
- a Department of Microbiology, Graduate School of Medicine , Kyoto University , Kyoto , Japan
| | - Takashi Nozawa
- a Department of Microbiology, Graduate School of Medicine , Kyoto University , Kyoto , Japan
| | - Atsuko Minowa-Nozawa
- a Department of Microbiology, Graduate School of Medicine , Kyoto University , Kyoto , Japan
| | - Hirotaka Toh
- a Department of Microbiology, Graduate School of Medicine , Kyoto University , Kyoto , Japan
| | - Shunsuke Yamada
- a Department of Microbiology, Graduate School of Medicine , Kyoto University , Kyoto , Japan
| | - Chihiro Aikawa
- a Department of Microbiology, Graduate School of Medicine , Kyoto University , Kyoto , Japan
| | - Ichiro Nakagawa
- a Department of Microbiology, Graduate School of Medicine , Kyoto University , Kyoto , Japan
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Structural determinants of Rab11 activation by the guanine nucleotide exchange factor SH3BP5. Nat Commun 2018; 9:3772. [PMID: 30217979 PMCID: PMC6138693 DOI: 10.1038/s41467-018-06196-z] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 08/14/2018] [Indexed: 12/18/2022] Open
Abstract
The GTPase Rab11 plays key roles in receptor recycling, oogenesis, autophagosome formation, and ciliogenesis. However, investigating Rab11 regulation has been hindered by limited molecular detail describing activation by cognate guanine nucleotide exchange factors (GEFs). Here, we present the structure of Rab11 bound to the GEF SH3BP5, along with detailed characterization of Rab-GEF specificity. The structure of SH3BP5 shows a coiled-coil architecture that mediates exchange through a unique Rab-GEF interaction. Furthermore, it reveals a rearrangement of the switch I region of Rab11 compared with solved Rab-GEF structures, with a constrained conformation when bound to SH3BP5. Mutation of switch I provides insights into the molecular determinants that allow for Rab11 selectivity over evolutionarily similar Rab GTPases present on Rab11-positive organelles. Moreover, we show that GEF-deficient mutants of SH3BP5 show greatly decreased Rab11 activation in cellular assays of active Rab11. Overall, our results give molecular insight into Rab11 regulation, and how Rab-GEF specificity is achieved.
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63
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Structural Basis for Regulation of Phosphoinositide Kinases and Their Involvement in Human Disease. Mol Cell 2018; 71:653-673. [DOI: 10.1016/j.molcel.2018.08.005] [Citation(s) in RCA: 185] [Impact Index Per Article: 26.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 06/22/2018] [Accepted: 07/30/2018] [Indexed: 01/09/2023]
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64
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A novel cross-talk between CXCR4 and PI4KIIIα in prostate cancer cells. Oncogene 2018; 38:332-344. [PMID: 30111818 PMCID: PMC6336684 DOI: 10.1038/s41388-018-0448-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Revised: 07/03/2018] [Accepted: 07/14/2018] [Indexed: 12/20/2022]
Abstract
Chemokine signaling regulates cell migration and tumor metastasis. CXCL12, a member of the chemokine family, and its receptor, CXCR4, a G protein coupled receptor (GPCR), are key mediators of prostate-cancer (PC) bone metastasis. In PC cells androgens activate CXCR4 gene expression and receptor signaling on lipid rafts, which induces protease expression and cancer cell invasion. To identify novel lipid-raft-associated CXCR4 regulators supporting invasion/metastasis, we performed a SILAC-based quantitative proteomic analysis of lipid-rafts derived from PC3 stable cell lines with overexpression or knockdown of CXCR4. This analysis identified the evolutionarily conserved phosphatidylinositol 4-kinase IIIα (PI4KIIIα), and SAC1 phosphatase that dephosphorylates phosphatidylinositol-4-phosphate as potential candidate CXCR4 regulators. CXCR4 interacted with PI4KIIIα membrane targeting machinery recruiting them to the plasma membrane for PI4P production. Consistent with this interaction, PI4KIIIα was found tightly linked to the CXCR4 induced PC cell invasion. Thus, ablation of PI4KIIIα in CXCR4-expressing PC3 cells reduced cellular invasion in response to a variety of chemokines. Immunofluorescence microscopy in CXCR4 expressing cells revealed localized production of PI4P on the invasive projections. Human tumor studies documented increased PI4KIIIα expression in metastatic tumors vs. the primary tumor counterparts, further supporting the PI4KIIIα role in tumor metastasis. Furthermore, we also identified an unexpected function of PI4KIIIα in GPCR signaling where CXCR4 regulates PI4KIIIα activity and mediate tumor metastasis. Together, our study identifies a novel cross-talk between PI4KIIIα and CXCR4 in promoting tumor metastasis and suggests that PI4KIIIα pharmacological targeting may have therapeutic benefit for advanced prostate cancer patients.
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65
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Mathews ES, Odom John AR. Tackling resistance: emerging antimalarials and new parasite targets in the era of elimination. F1000Res 2018; 7. [PMID: 30135714 PMCID: PMC6073090 DOI: 10.12688/f1000research.14874.1] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 07/26/2018] [Indexed: 12/27/2022] Open
Abstract
Malaria remains a significant contributor to global human mortality, and roughly half the world’s population is at risk for infection with
Plasmodium spp. parasites. Aggressive control measures have reduced the global prevalence of malaria significantly over the past decade. However, resistance to available antimalarials continues to spread, including resistance to the widely used artemisinin-based combination therapies. Novel antimalarial compounds and therapeutic targets are greatly needed. This review will briefly discuss several promising current antimalarial development projects, including artefenomel, ferroquine, cipargamin, SJ733, KAF156, MMV048, and tafenoquine. In addition, we describe recent large-scale genetic and resistance screens that have been instrumental in target discovery. Finally, we highlight new antimalarial targets, which include essential transporters and proteases. These emerging antimalarial compounds and therapeutic targets have the potential to overcome multi-drug resistance in ongoing efforts toward malaria elimination.
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Affiliation(s)
- Emily S Mathews
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Audrey R Odom John
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri, USA.,Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, USA
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66
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Reuberson J, Horsley H, Franklin RJ, Ford D, Neuss J, Brookings D, Huang Q, Vanderhoydonck B, Gao LJ, Jang MY, Herdewijn P, Ghawalkar A, Fallah-Arani F, Khan AR, Henshall J, Jairaj M, Malcolm S, Ward E, Shuttleworth L, Lin Y, Li S, Louat T, Waer M, Herman J, Payne A, Ceska T, Doyle C, Pitt W, Calmiano M, Augustin M, Steinbacher S, Lammens A, Allen R. Discovery of a Potent, Orally Bioavailable PI4KIIIβ Inhibitor (UCB9608) Able To Significantly Prolong Allogeneic Organ Engraftment in Vivo. J Med Chem 2018; 61:6705-6723. [PMID: 29952567 DOI: 10.1021/acs.jmedchem.8b00521] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The primary target of a novel series of immunosuppressive 7-piperazin-1-ylthiazolo[5,4- d]pyrimidin-5-amines was identified as the lipid kinase, PI4KIIIβ. Evaluation of the series highlighted their poor solubility and unwanted off-target activities. A medicinal chemistry strategy was put in place to optimize physicochemical properties within the series, while maintaining potency and improving selectivity over other lipid kinases. Compound 22 was initially identified and profiled in vivo, before further modifications led to the discovery of 44 (UCB9608), a vastly more soluble, selective compound with improved metabolic stability and excellent pharmacokinetic profile. A co-crystal structure of 44 with PI4KIIIβ was solved, confirming the binding mode of this class of inhibitor. The much-improved in vivo profile of 44 positions it as an ideal tool compound to further establish the link between PI4KIIIβ inhibition and prolonged allogeneic organ engraftment, and suppression of immune responses in vivo.
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Affiliation(s)
- James Reuberson
- UCB Pharma , 208 Bath Road , Slough , Berkshire SL1 3WE , United Kingdom
| | - Helen Horsley
- UCB Pharma , 208 Bath Road , Slough , Berkshire SL1 3WE , United Kingdom
| | - Richard J Franklin
- UCB Pharma , 208 Bath Road , Slough , Berkshire SL1 3WE , United Kingdom
| | - Daniel Ford
- UCB Pharma , 208 Bath Road , Slough , Berkshire SL1 3WE , United Kingdom
| | - Judi Neuss
- UCB Pharma , 208 Bath Road , Slough , Berkshire SL1 3WE , United Kingdom
| | - Daniel Brookings
- UCB Pharma , 208 Bath Road , Slough , Berkshire SL1 3WE , United Kingdom
| | - Qiuya Huang
- Interface Valorization Platform , KU Leuven , Campus St.-Rafaël, Blok I, 8°, Kapucijnenvoer 33 B 7001 , 3000 Leuven , Belgium
| | - Bart Vanderhoydonck
- Interface Valorization Platform , KU Leuven , Campus St.-Rafaël, Blok I, 8°, Kapucijnenvoer 33 B 7001 , 3000 Leuven , Belgium
| | - Ling-Jie Gao
- Interface Valorization Platform , KU Leuven , Campus St.-Rafaël, Blok I, 8°, Kapucijnenvoer 33 B 7001 , 3000 Leuven , Belgium
| | - Mi-Yeon Jang
- Interface Valorization Platform , KU Leuven , Campus St.-Rafaël, Blok I, 8°, Kapucijnenvoer 33 B 7001 , 3000 Leuven , Belgium
| | - Piet Herdewijn
- Interface Valorization Platform , KU Leuven , Campus St.-Rafaël, Blok I, 8°, Kapucijnenvoer 33 B 7001 , 3000 Leuven , Belgium
| | - Anant Ghawalkar
- SAI Life Sciences Ltd , International Biotech Park , Hinjewadi, Pune 411 057 , India
| | | | - Adnan R Khan
- UCB Pharma , 208 Bath Road , Slough , Berkshire SL1 3WE , United Kingdom
| | - Jamie Henshall
- UCB Pharma , 208 Bath Road , Slough , Berkshire SL1 3WE , United Kingdom
| | - Mark Jairaj
- UCB Pharma , 208 Bath Road , Slough , Berkshire SL1 3WE , United Kingdom
| | - Sarah Malcolm
- UCB Pharma , 208 Bath Road , Slough , Berkshire SL1 3WE , United Kingdom
| | - Eleanor Ward
- UCB Pharma , 208 Bath Road , Slough , Berkshire SL1 3WE , United Kingdom
| | | | - Yuan Lin
- Interface Valorization Platform , KU Leuven , Campus St.-Rafaël, Blok I, 8°, Kapucijnenvoer 33 B 7001 , 3000 Leuven , Belgium
| | - Shengqiao Li
- Interface Valorization Platform , KU Leuven , Campus St.-Rafaël, Blok I, 8°, Kapucijnenvoer 33 B 7001 , 3000 Leuven , Belgium
| | - Thierry Louat
- Interface Valorization Platform , KU Leuven , Campus St.-Rafaël, Blok I, 8°, Kapucijnenvoer 33 B 7001 , 3000 Leuven , Belgium
| | - Mark Waer
- Interface Valorization Platform , KU Leuven , Campus St.-Rafaël, Blok I, 8°, Kapucijnenvoer 33 B 7001 , 3000 Leuven , Belgium
| | - Jean Herman
- Interface Valorization Platform , KU Leuven , Campus St.-Rafaël, Blok I, 8°, Kapucijnenvoer 33 B 7001 , 3000 Leuven , Belgium
| | - Andrew Payne
- UCB Pharma , 208 Bath Road , Slough , Berkshire SL1 3WE , United Kingdom
| | - Tom Ceska
- UCB Pharma , 208 Bath Road , Slough , Berkshire SL1 3WE , United Kingdom
| | - Carl Doyle
- UCB Pharma , 208 Bath Road , Slough , Berkshire SL1 3WE , United Kingdom
| | - Will Pitt
- UCB Pharma , 208 Bath Road , Slough , Berkshire SL1 3WE , United Kingdom
| | - Mark Calmiano
- UCB Pharma , 208 Bath Road , Slough , Berkshire SL1 3WE , United Kingdom
| | - Martin Augustin
- Proteros Biostructures GmbH , Bunsenstrasse 7a , 82152 Martinsried , Germany
| | - Stefan Steinbacher
- Proteros Biostructures GmbH , Bunsenstrasse 7a , 82152 Martinsried , Germany
| | - Alfred Lammens
- Proteros Biostructures GmbH , Bunsenstrasse 7a , 82152 Martinsried , Germany
| | - Rodger Allen
- UCB Pharma , 208 Bath Road , Slough , Berkshire SL1 3WE , United Kingdom
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67
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Dornan GL, Dalwadi U, Hamelin DJ, Hoffmann RM, Yip CK, Burke JE. Probing the Architecture, Dynamics, and Inhibition of the PI4KIIIα/TTC7/FAM126 Complex. J Mol Biol 2018; 430:3129-3142. [PMID: 30031006 DOI: 10.1016/j.jmb.2018.07.020] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 07/11/2018] [Accepted: 07/16/2018] [Indexed: 11/16/2022]
Abstract
Phosphatidylinositol 4-kinase IIIα (PI4KIIIα) is the lipid kinase primarily responsible for generating the lipid phosphatidylinositol 4-phosphate (PI4P) at the plasma membrane, which acts as the substrate for generation of the signaling lipids PIP2 and PIP3. PI4KIIIα forms a large heterotrimeric complex with two regulatory partners, TTC7 and FAM126. We describe using an integrated electron microscopy and hydrogen-deuterium exchange mass spectrometry (HDX-MS) approach to probe the architecture and dynamics of the complex of PI4KIIIα/TTC7/FAM126. HDX-MS reveals that the majority of the PI4KIIIα sequence was protected from exchange in short deuterium pulse experiments, suggesting presence of secondary structure, even in putative unstructured regions. Negative stain electron microscopy reveals the shape and architecture of the full-length complex, revealing an overall dimer of PI4KIIIα/TTC7/FAM126 trimers. HDX-MS reveals conformational changes in the TTC7/FAM126 complex upon binding PI4KIIIα, including both at the direct TTC7-PI4KIIIα interface and at the putative membrane binding surface. Finally, HDX-MS experiments of PI4KIIIα bound to the highly potent and selective inhibitor GSK-A1 compared to that bound to the non-specific inhibitor PIK93 revealed substantial conformational changes throughout an extended region of the kinase domain. Many of these changes were distant from the putative inhibitor binding site, showing a large degree of allosteric conformational changes that occur upon inhibitor binding. Overall, our results reveal novel insight into the regulation of PI4KIIIα by its regulatory proteins TTC7/FAM126, as well as additional dynamic information on how selective inhibition of PI4KIIIα is achieved.
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Affiliation(s)
- Gillian L Dornan
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia, Canada V8W 2Y2
| | - Udit Dalwadi
- Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - David J Hamelin
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia, Canada V8W 2Y2
| | - Reece M Hoffmann
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia, Canada V8W 2Y2
| | - Calvin K Yip
- Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - John E Burke
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia, Canada V8W 2Y2.
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68
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Ma X, Liu K, Li J, Li H, Li J, Liu Y, Yang C, Liang H. A non-canonical GTPase interaction enables ORP1L-Rab7-RILP complex formation and late endosome positioning. J Biol Chem 2018; 293:14155-14164. [PMID: 30012887 DOI: 10.1074/jbc.ra118.001854] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Revised: 07/09/2018] [Indexed: 01/06/2023] Open
Abstract
Endosomal transport represents the primary mode for intracellular trafficking and signaling transduction and thus has to be tightly controlled. The molecular processes controlling the endosomal positioning utilize several large protein complexes, one of which contains the small GTPase Rab7, Rab-interacting lysosomal protein (RILP), and oxysterol-binding protein-related protein 1 (ORP1L). Rab7 is known to interact with RILP through a canonical binding site termed the effector-interacting switch region, but it is not clear how Rab7 interacts with ORP1L, limiting our understanding of the overall process. Here, we report structural and biochemical investigation of the Rab7-ORP1L interaction. We found that, contrary to prior studies, the interaction between Rab7 and the N-terminal ankyrin repeat domain (ARDN) of ORP1L is independent of Rab7's GTP- or GDP-binding state. Moreover, we show that Rab7 interacts with ORP1L ARDN via a unique region consisting of helix3 (α3) and 310-helix 2 (η2). This architecture leaves the canonical effector-interacting switch regions available for RILP binding and thus allows formation of the ORP1L-Rab7-RILP tripartite complex. Mutational disruption of the interacting interface between ORP1L and Rab7 compromised the ability of ORP1L-Rab7-RILP to regulate the late endosome positioning. Collectively, our results again manifested the versatility in the interaction between GTPase and its effector.
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Affiliation(s)
- Xinli Ma
- From the National Laboratory of Biomacromolecules, Institute of Biophysics and.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Kai Liu
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China.,State Key laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.,State Key Laboratory of Utilization and Conservation of Bio-Resources in Yunnan and.,Life Science Center and School of Life Sciences, Yunnan University, Kunming 650500, China, and
| | - Jian Li
- From the National Laboratory of Biomacromolecules, Institute of Biophysics and
| | - Huanhuan Li
- From the National Laboratory of Biomacromolecules, Institute of Biophysics and.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jun Li
- From the National Laboratory of Biomacromolecules, Institute of Biophysics and
| | - Yingfang Liu
- From the National Laboratory of Biomacromolecules, Institute of Biophysics and.,Schools of Medicine and
| | - Chonglin Yang
- State Key laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China, .,State Key Laboratory of Utilization and Conservation of Bio-Resources in Yunnan and.,Life Science Center and School of Life Sciences, Yunnan University, Kunming 650500, China, and
| | - Huanhuan Liang
- From the National Laboratory of Biomacromolecules, Institute of Biophysics and .,Pharmaceutical Sciences (Shenzhen), Sun Yat-sen University, Guangzhou 510275, China
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69
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Melia CE, van der Schaar HM, Lyoo H, Limpens RWAL, Feng Q, Wahedi M, Overheul GJ, van Rij RP, Snijder EJ, Koster AJ, Bárcena M, van Kuppeveld FJM. Escaping Host Factor PI4KB Inhibition: Enterovirus Genomic RNA Replication in the Absence of Replication Organelles. Cell Rep 2018; 21:587-599. [PMID: 29045829 PMCID: PMC5656745 DOI: 10.1016/j.celrep.2017.09.068] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 08/25/2017] [Accepted: 09/20/2017] [Indexed: 01/15/2023] Open
Abstract
Enteroviruses reorganize cellular endomembranes into replication organelles (ROs) for genome replication. Although enterovirus replication depends on phosphatidylinositol 4-kinase type IIIβ (PI4KB), its role, and that of its product, phosphatidylinositol 4-phosphate (PI4P), is only partially understood. Exploiting a mutant coxsackievirus resistant to PI4KB inhibition, we show that PI4KB activity has distinct functions both in proteolytic processing of the viral polyprotein and in RO biogenesis. The escape mutation rectifies a proteolytic processing defect imposed by PI4KB inhibition, pointing to a possible escape mechanism. Remarkably, under PI4KB inhibition, the mutant virus could replicate its genome in the absence of ROs, using instead the Golgi apparatus. This impaired RO biogenesis provided an opportunity to investigate the proposed role of ROs in shielding enteroviral RNA from cellular sensors. Neither accelerated sensing of viral RNA nor enhanced innate immune responses was observed. Together, our findings challenge the notion that ROs are indispensable for enterovirus genome replication and immune evasion. PI4KB activity expedites the formation of coxsackievirus replication organelles (ROs) PI4KB inhibition impairs polyprotein processing, which is rescued by a 3A mutation Upon PI4KB inhibition, this mutant replicates at the Golgi in the absence of ROs Innate immune responses are not enhanced when RO biogenesis is delayed
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Affiliation(s)
- Charlotte E Melia
- Department of Molecular Cell Biology, Leiden University Medical Center, Leiden 2333 ZC, the Netherlands
| | - Hilde M van der Schaar
- Department of Infectious Diseases & Immunology, Utrecht University, Utrecht 3584 CL, the Netherlands
| | - Heyrhyoung Lyoo
- Department of Infectious Diseases & Immunology, Utrecht University, Utrecht 3584 CL, the Netherlands
| | - Ronald W A L Limpens
- Department of Molecular Cell Biology, Leiden University Medical Center, Leiden 2333 ZC, the Netherlands
| | - Qian Feng
- Department of Infectious Diseases & Immunology, Utrecht University, Utrecht 3584 CL, the Netherlands
| | - Maryam Wahedi
- Department of Infectious Diseases & Immunology, Utrecht University, Utrecht 3584 CL, the Netherlands
| | - Gijs J Overheul
- Department of Medical Microbiology, Radboud Institute for Molecular Life Sciences, Nijmegen 6525 GA, the Netherlands
| | - Ronald P van Rij
- Department of Medical Microbiology, Radboud Institute for Molecular Life Sciences, Nijmegen 6525 GA, the Netherlands
| | - Eric J Snijder
- Department of Medical Microbiology, Leiden University Medical Center, Leiden 2333 ZA, the Netherlands
| | - Abraham J Koster
- Department of Molecular Cell Biology, Leiden University Medical Center, Leiden 2333 ZC, the Netherlands
| | - Montserrat Bárcena
- Department of Molecular Cell Biology, Leiden University Medical Center, Leiden 2333 ZC, the Netherlands.
| | - Frank J M van Kuppeveld
- Department of Infectious Diseases & Immunology, Utrecht University, Utrecht 3584 CL, the Netherlands.
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70
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Kandepedu N, Gonzàlez Cabrera D, Eedubilli S, Taylor D, Brunschwig C, Gibhard L, Njoroge M, Lawrence N, Paquet T, Eyermann CJ, Spangenberg T, Basarab GS, Street LJ, Chibale K. Identification, Characterization, and Optimization of 2,8-Disubstituted-1,5-naphthyridines as Novel Plasmodium falciparum Phosphatidylinositol-4-kinase Inhibitors with in Vivo Efficacy in a Humanized Mouse Model of Malaria. J Med Chem 2018; 61:5692-5703. [DOI: 10.1021/acs.jmedchem.8b00648] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Nishanth Kandepedu
- Drug Discovery and Development Centre (H3D), University of Cape Town, Rondebosch 7701, South Africa
| | - Diego Gonzàlez Cabrera
- Drug Discovery and Development Centre (H3D), University of Cape Town, Rondebosch 7701, South Africa
| | - Srinivas Eedubilli
- Drug Discovery and Development Centre (H3D), University of Cape Town, Rondebosch 7701, South Africa
| | - Dale Taylor
- Drug Discovery and Development Centre (H3D), DMPK/Pharmacology, University of Cape Town, Observatory 7925, South Africa
| | - Christel Brunschwig
- Drug Discovery and Development Centre (H3D), DMPK/Pharmacology, University of Cape Town, Observatory 7925, South Africa
| | - Liezl Gibhard
- Drug Discovery and Development Centre (H3D), DMPK/Pharmacology, University of Cape Town, Observatory 7925, South Africa
| | - Mathew Njoroge
- Drug Discovery and Development Centre (H3D), DMPK/Pharmacology, University of Cape Town, Observatory 7925, South Africa
| | - Nina Lawrence
- Drug Discovery and Development Centre (H3D), DMPK/Pharmacology, University of Cape Town, Observatory 7925, South Africa
| | - Tanya Paquet
- Drug Discovery and Development Centre (H3D), University of Cape Town, Rondebosch 7701, South Africa
| | - Charles J. Eyermann
- Drug Discovery and Development Centre (H3D), University of Cape Town, Rondebosch 7701, South Africa
| | - Thomas Spangenberg
- Merck Global Health Institute, Ares Trading S.A., a subsidiary of Merck KGaA (Darmstadt, Germany), Coinsins 1267, Switzerland
| | - Gregory S. Basarab
- Drug Discovery and Development Centre (H3D), University of Cape Town, Rondebosch 7701, South Africa
| | - Leslie J. Street
- Drug Discovery and Development Centre (H3D), University of Cape Town, Rondebosch 7701, South Africa
| | - Kelly Chibale
- Drug Discovery and Development Centre (H3D), University of Cape Town, Rondebosch 7701, South Africa
- South African Medical Research Council, Drug Discovery and Development Research Unit, Department of Chemistry and Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Rondebosch 7701, South Africa
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71
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Kumar AP, Lukman S. Allosteric binding sites in Rab11 for potential drug candidates. PLoS One 2018; 13:e0198632. [PMID: 29874286 PMCID: PMC5991966 DOI: 10.1371/journal.pone.0198632] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Accepted: 05/22/2018] [Indexed: 12/19/2022] Open
Abstract
Rab11 is an important protein subfamily in the RabGTPase family. These proteins physiologically function as key regulators of intracellular membrane trafficking processes. Pathologically, Rab11 proteins are implicated in many diseases including cancers, neurodegenerative diseases and type 2 diabetes. Although they are medically important, no previous study has found Rab11 allosteric binding sites where potential drug candidates can bind to. In this study, by employing multiple clustering approaches integrating principal component analysis, independent component analysis and locally linear embedding, we performed structural analyses of Rab11 and identified eight representative structures. Using these representatives to perform binding site mapping and virtual screening, we identified two novel binding sites in Rab11 and small molecules that can preferentially bind to different conformations of these sites with high affinities. After identifying the binding sites and the residue interaction networks in the representatives, we computationally showed that these binding sites may allosterically regulate Rab11, as these sites communicate with switch 2 region that binds to GTP/GDP. These two allosteric binding sites in Rab11 are also similar to two allosteric pockets in Ras that we discovered previously.
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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
| | - 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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72
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Desrochers GF, Cornacchia C, McKay CS, Pezacki JP. Activity-Based Phosphatidylinositol Kinase Probes Detect Changes to Protein-Protein Interactions During Hepatitis C Virus Replication. ACS Infect Dis 2018; 4:752-757. [PMID: 29509402 DOI: 10.1021/acsinfecdis.8b00047] [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: 01/19/2023]
Abstract
Protein-protein interactions are integral to host-virus interactions and can contribute significantly to enzyme regulation by changing the localization of both host and viral enzymes within the cell, inducing conformational change relevant to enzyme activity or recruiting other additional proteins to form functional complexes. Identifying the interactors of active enzymes using an activity-based protein profiling probe has allowed us to characterize both normal enzyme activation mechanisms and the manner by which these mechanisms are hijacked and altered by the hepatitis C virus (HCV). Here, we report use of a novel activity-based probe, PIKBPyne, which labels phosphatidylinositol kinases (PIKs) in an activity-based manner, to investigate HCV-dependent changes in protein-protein interactions for PI4KB. Herein, we report the synthesis of new variations on PIKBPyne, compare their ability to label the interacting partners of PI4KB, and demonstrate the utility of our approach in characterizing virus-mediated changes to host function.
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Affiliation(s)
- Geneviève F. Desrochers
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, 10 Marie Curie Pvt., Ottawa, Ontario K1N 6N5, Canada
| | - Christina Cornacchia
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, 10 Marie Curie Pvt., Ottawa, Ontario K1N 6N5, Canada
| | - Craig S. McKay
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, 10 Marie Curie Pvt., Ottawa, Ontario K1N 6N5, Canada
| | - John Paul Pezacki
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, 10 Marie Curie Pvt., Ottawa, Ontario K1N 6N5, Canada
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa, 451 Smyth Rd., Ottawa, Ontario K1H 8M5, Canada
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73
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74
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Pylypenko O, Hammich H, Yu IM, Houdusse A. Rab GTPases and their interacting protein partners: Structural insights into Rab functional diversity. Small GTPases 2018. [PMID: 28632484 DOI: 10.1080/215412481336191] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/23/2023] Open
Abstract
Rab molecular switches are key players in defining membrane identity and regulating intracellular trafficking events in eukaryotic cells. In spite of their global structural similarity, Rab-family members acquired particular features that allow them to perform specific cellular functions. The overall fold and local sequence conservations enable them to utilize a common machinery for prenylation and recycling; while individual Rab structural differences determine interactions with specific partners such as GEFs, GAPs and effector proteins. These interactions orchestrate the spatiotemporal regulation of Rab localization and their turning ON and OFF, leading to tightly controlled Rab-specific functionalities such as membrane composition modifications, recruitment of molecular motors for intracellular trafficking, or recruitment of scaffold proteins that mediate interactions with downstream partners, as well as actin cytoskeleton regulation. In this review we summarize structural information on Rab GTPases and their complexes with protein partners in the context of partner binding specificity and functional outcomes of their interactions in the cell.
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Affiliation(s)
- Olena Pylypenko
- a Structural Motility, Institut Curie , PSL Research University, CNRS, UMR 144 , Paris , France
| | - Hussein Hammich
- a Structural Motility, Institut Curie , PSL Research University, CNRS, UMR 144 , Paris , France
- b Sorbonne Universités , UPMC Univ Paris 06, Sorbonne Universités, IFD , Paris , France
| | - I-Mei Yu
- a Structural Motility, Institut Curie , PSL Research University, CNRS, UMR 144 , Paris , France
| | - Anne Houdusse
- a Structural Motility, Institut Curie , PSL Research University, CNRS, UMR 144 , Paris , France
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75
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Dubankova A, Humpolickova J, Klima M, Boura E. Negative charge and membrane-tethered viral 3B cooperate to recruit viral RNA dependent RNA polymerase 3D pol. Sci Rep 2017; 7:17309. [PMID: 29230036 PMCID: PMC5725453 DOI: 10.1038/s41598-017-17621-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Accepted: 11/29/2017] [Indexed: 12/28/2022] Open
Abstract
Most single stranded plus RNA viruses hijack phosphatidylinositol 4-kinases (PI4Ks) to generate membranes highly enriched in phosphatidylinositol 4-phosphate (PI4P). These membranous compartments known as webs, replication factories or replication organelles are essential for viral replication because they provide protection from the innate intracellular immune response while serving as platforms for viral replication. Using purified recombinant proteins and biomimetic model membranes we show that the nonstructural viral 3A protein is sufficient to promote membrane hyper-phosphorylation given the proper intracellular cofactors (PI4KB and ACBD3). However, our bio-mimetic in vitro reconstitution assay revealed that rather than the presence of PI4P specifically, negative charge alone is sufficient for the recruitment of 3Dpol enzymes to the surface of the lipid bilayer. Additionally, we show that membrane tethered viral 3B protein (also known as Vpg) works in combination with the negative charge to increase the efficiency of membrane recruitment of 3Dpol.
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Affiliation(s)
- Anna Dubankova
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague, Czech Republic
| | - Jana Humpolickova
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague, Czech Republic
| | - Martin Klima
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague, Czech Republic
| | - Evzen Boura
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague, Czech Republic.
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76
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Gulluni F, Martini M, Hirsch E. Cytokinetic Abscission: Phosphoinositides and ESCRTs Direct the Final Cut. J Cell Biochem 2017; 118:3561-3568. [PMID: 28419521 DOI: 10.1002/jcb.26066] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 04/14/2017] [Indexed: 01/23/2023]
Abstract
Cytokinetic abscission involves the fine and regulated recruitment of membrane remodeling proteins that participate in the abscission of the intracellular bridge that connects the two dividing cells. This essential process is mediated by the concomitant activity of the endosomal sorting complex required for transport (ESCRT) and the vesicular trafficking directed to the midbody. Phosphoinositides (PtdIns), produced at plasma membrane, and endosomes, act as molecular intermediates by recruiting effector proteins involved in multiple cellular processes, such as intracellular signaling, endo- and exo-cytosis, and membrane remodeling events. Emerging evidences suggest that PtdIns have an active role in recruiting key elements that control the stability and the remodeling of the cytoskeleton from the furrow ingression to the abscission, at the end of cytokinesis. Accordingly, a possible concomitant and coordinated activity between PtdIns production and ESCRT machinery assembly could also exist and recent findings are pointing the attention on poorly understood ESCRT subunits potentially able to associate with PtdIns rich membranes. Although further studies are required to link PtdIns to ESCRT machinery during abscission, this might represent a promising field of study. J. Cell. Biochem. 118: 3561-3568, 2017. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Federico Gulluni
- Department of Molecular Biotechnology and Health Sciences, University of Turin, Turin, Italy
| | - Miriam Martini
- Department of Molecular Biotechnology and Health Sciences, University of Turin, Turin, Italy
| | - Emilio Hirsch
- Department of Molecular Biotechnology and Health Sciences, University of Turin, Turin, Italy
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77
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Chalupska D, Eisenreichova A, Różycki B, Rezabkova L, Humpolickova J, Klima M, Boura E. Structural analysis of phosphatidylinositol 4-kinase IIIβ (PI4KB) - 14-3-3 protein complex reveals internal flexibility and explains 14-3-3 mediated protection from degradation in vitro. J Struct Biol 2017; 200:36-44. [PMID: 28864297 DOI: 10.1016/j.jsb.2017.08.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Revised: 08/26/2017] [Accepted: 08/28/2017] [Indexed: 12/31/2022]
Abstract
Phosphatidylinositol 4-kinase IIIβ (PI4KB) is responsible for the synthesis of the Golgi and trans-Golgi network (TGN) pool of phosphatidylinositol 4-phospahte (PI4P). PI4P is the defining lipid hallmark of Golgi and TGN and also serves as a signaling lipid and as a precursor for higher phosphoinositides. In addition, PI4KB is hijacked by many single stranded plus RNA (+RNA) viruses to generate PI4P-rich membranes that serve as viral replication organelles. Given the importance of this enzyme in cells, it has to be regulated. 14-3-3 proteins bind PI4KB upon its phosphorylation by protein kinase D, however, the structural basis of PI4KB recognition by 14-3-3 proteins is unknown. Here, we characterized the PI4KB:14-3-3 protein complex biophysically and structurally. We discovered that the PI4KB:14-3-3 protein complex is tight and is formed with 2:2 stoichiometry. Surprisingly, the enzymatic activity of PI4KB is not directly modulated by 14-3-3 proteins. However, 14-3-3 proteins protect PI4KB from proteolytic degradation in vitro. Our structural analysis revealed that the PI4KB:14-3-3 protein complex is flexible but mostly within the disordered regions connecting the 14-3-3 binding site of the PI4KB with the rest of the PI4KB enzyme. It also predicted no direct modulation of PI4KB enzymatic activity by 14-3-3 proteins and that 14-3-3 binding will not interfere with PI4KB recruitment to the membrane by the ACBD3 protein. In addition, the structural analysis explains the observed protection from degradation; it revealed that several disordered regions of PI4KB become protected from proteolytical degradation upon 14-3-3 binding. All the structural predictions were subsequently biochemically validated.
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Affiliation(s)
- Dominika Chalupska
- Institute of Organic Chemistry and Biochemistry AS CR, v.v.i., Flemingovo nam. 2., 166 10 Prague 6, Czech Republic
| | - Andrea Eisenreichova
- Institute of Organic Chemistry and Biochemistry AS CR, v.v.i., Flemingovo nam. 2., 166 10 Prague 6, Czech Republic
| | - Bartosz Różycki
- Institute of Physics, Polish Academy of Sciences, Al. Lotnikow 32/46, 02-668 Warsaw, Poland
| | - Lenka Rezabkova
- Laboratory of Biomolecular Research, Department of Biology and Chemistry, Paul Scherrer Institute, 5232, Villigen PSI, Switzerland
| | - Jana Humpolickova
- Institute of Organic Chemistry and Biochemistry AS CR, v.v.i., Flemingovo nam. 2., 166 10 Prague 6, Czech Republic
| | - Martin Klima
- Institute of Organic Chemistry and Biochemistry AS CR, v.v.i., Flemingovo nam. 2., 166 10 Prague 6, Czech Republic
| | - Evzen Boura
- Institute of Organic Chemistry and Biochemistry AS CR, v.v.i., Flemingovo nam. 2., 166 10 Prague 6, Czech Republic.
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78
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Masson GR, Jenkins ML, Burke JE. An overview of hydrogen deuterium exchange mass spectrometry (HDX-MS) in drug discovery. Expert Opin Drug Discov 2017; 12:981-994. [PMID: 28770632 DOI: 10.1080/17460441.2017.1363734] [Citation(s) in RCA: 89] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
INTRODUCTION Hydrogen deuterium exchange mass spectrometry (HDX-MS) is a powerful methodology to study protein dynamics, protein folding, protein-protein interactions, and protein small molecule interactions. The development of novel methodologies and technical advancements in mass spectrometers has greatly expanded the accessibility and acceptance of this technique within both academia and industry. Areas covered: This review examines the theoretical basis of how amide exchange occurs, how different mass spectrometer approaches can be used for HDX-MS experiments, as well as the use of HDX-MS in drug development, specifically focusing on how HDX-MS is used to characterize bio-therapeutics, and its use in examining protein-protein and protein small molecule interactions. Expert opinion: HDX-MS has been widely accepted within the pharmaceutical industry for the characterization of bio-therapeutics as well as in the mapping of antibody drug epitopes. However, there is room for this technique to be more widely used in the drug discovery process. This is particularly true in the use of HDX-MS as a complement to other high-resolution structural approaches, as well as in the development of small molecule therapeutics that can target both active-site and allosteric binding sites.
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Affiliation(s)
- Glenn R Masson
- a Protein and Nucleic Acid Chemistry Division , MRC Laboratory of Molecular Biology , Cambridge , UK
| | - Meredith L Jenkins
- b Department of Biochemistry and Microbiology , University of Victoria , Victoria , Canada
| | - John E Burke
- b Department of Biochemistry and Microbiology , University of Victoria , Victoria , Canada
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79
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Arita M, Dobrikov G, Pürstinger G, Galabov AS. Allosteric Regulation of Phosphatidylinositol 4-Kinase III Beta by an Antipicornavirus Compound MDL-860. ACS Infect Dis 2017; 3:585-594. [PMID: 28605587 DOI: 10.1021/acsinfecdis.7b00053] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
MDL-860 is a broad-spectrum antipicornavirus compound discovered in 1982 and one of the few promising candidates effective in in vivo virus infection. Despite the effectiveness, the target and the mechanism of action of MDL-860 remain unknown. Here, we have characterized antipoliovirus activity of MDL-860 and identified host phosphatidylinositol-4 kinase III beta (PI4KB) as the target. MDL-860 treatment caused covalent modification and irreversible inactivation of PI4KB. A cysteine residue at amino acid 646 of PI4KB, which locates at the bottom of a surface pocket apart from the active site, was identified as the target site of MDL-860. This work reveals the mechanism of action of this class of PI4KB inhibitors and offers insights into novel allosteric regulation of PI4KB activity.
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Affiliation(s)
- Minetaro Arita
- Department
of Virology II, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashimurayama-shi, Tokyo 208-0011, Japan
| | - Georgi Dobrikov
- Institute
of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, Academician Georgi Bonchev Street, Bl. 9, 1113 Sofia, Bulgaria
| | - Gerhard Pürstinger
- Institute
of Pharmacy, University of Innsbruck, Innrain 80/82, A-6020 Innsbruck, Austria
| | - Angel S. Galabov
- The
Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, 26 Academician Georgi Bonchev Street, 1113 Sofia, Bulgaria
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80
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Pylypenko O, Hammich H, Yu IM, Houdusse A. Rab GTPases and their interacting protein partners: Structural insights into Rab functional diversity. Small GTPases 2017. [PMID: 28632484 PMCID: PMC5902227 DOI: 10.1080/21541248.2017.1336191] [Citation(s) in RCA: 98] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Rab molecular switches are key players in defining membrane identity and regulating intracellular trafficking events in eukaryotic cells. In spite of their global structural similarity, Rab-family members acquired particular features that allow them to perform specific cellular functions. The overall fold and local sequence conservations enable them to utilize a common machinery for prenylation and recycling; while individual Rab structural differences determine interactions with specific partners such as GEFs, GAPs and effector proteins. These interactions orchestrate the spatiotemporal regulation of Rab localization and their turning ON and OFF, leading to tightly controlled Rab-specific functionalities such as membrane composition modifications, recruitment of molecular motors for intracellular trafficking, or recruitment of scaffold proteins that mediate interactions with downstream partners, as well as actin cytoskeleton regulation. In this review we summarize structural information on Rab GTPases and their complexes with protein partners in the context of partner binding specificity and functional outcomes of their interactions in the cell.
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Affiliation(s)
- Olena Pylypenko
- a Structural Motility, Institut Curie , PSL Research University, CNRS, UMR 144 , Paris , France
| | - Hussein Hammich
- a Structural Motility, Institut Curie , PSL Research University, CNRS, UMR 144 , Paris , France.,b Sorbonne Universités , UPMC Univ Paris 06, Sorbonne Universités, IFD , Paris , France
| | - I-Mei Yu
- a Structural Motility, Institut Curie , PSL Research University, CNRS, UMR 144 , Paris , France
| | - Anne Houdusse
- a Structural Motility, Institut Curie , PSL Research University, CNRS, UMR 144 , Paris , France
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81
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Analysis of phosphoinositide 3-kinase inhibitors by bottom-up electron-transfer dissociation hydrogen/deuterium exchange mass spectrometry. Biochem J 2017; 474:1867-1877. [PMID: 28381646 PMCID: PMC5544108 DOI: 10.1042/bcj20170127] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 04/03/2017] [Accepted: 04/05/2017] [Indexed: 12/22/2022]
Abstract
Until recently, one of the major limitations of hydrogen/deuterium exchange mass spectrometry (HDX-MS) was the peptide-level resolution afforded by proteolytic digestion. This limitation can be selectively overcome through the use of electron-transfer dissociation to fragment peptides in a manner that allows the retention of the deuterium signal to produce hydrogen/deuterium exchange tandem mass spectrometry (HDX-MS/MS). Here, we describe the application of HDX-MS/MS to structurally screen inhibitors of the oncogene phosphoinositide 3-kinase catalytic p110α subunit. HDX-MS/MS analysis is able to discern a conserved mechanism of inhibition common to a range of inhibitors. Owing to the relatively minor amounts of protein required, this technique may be utilised in pharmaceutical development for screening potential therapeutics.
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82
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Daboussi L, Costaguta G, Ghukasyan R, Payne GS. Conserved role for Gga proteins in phosphatidylinositol 4-kinase localization to the trans-Golgi network. Proc Natl Acad Sci U S A 2017; 114:3433-3438. [PMID: 28289207 PMCID: PMC5380026 DOI: 10.1073/pnas.1615163114] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Phosphoinositides serve as key membrane determinants for assembly of clathrin coat proteins that drive formation of clathrin-coated vesicles. At the trans-Golgi network (TGN), phosphatidylinositol 4-phosphate (PtdIns4P) plays important roles in recruitment of two major clathrin adaptors, Gga (Golgi-localized, gamma-adaptin ear homology, Arf-binding) proteins and the AP-1 (assembly protein-1) complex. The molecular mechanisms that mediate localization of phosphatidylinositol kinases responsible for synthesis of PtdIns4P at the TGN are not well characterized. We identify two motifs in the yeast phosphatidylinositol 4-kinase, Pik1, which are required for binding to the VHS domain of Gga2. Mutations in these motifs that inhibit Gga2-VHS binding resulted in reduced Pik1 localization and delayed accumulation of PtdIns4P and recruitment of AP-1 to the TGN. The Pik1 homolog in mammals, PI4KIIIβ, interacted preferentially with the VHS domain of GGA2 compared with VHS domains of GGA1 and GGA3. Depletion of GGA2, but not GGA1 or GGA3, specifically affected PI4KIIIβ localization. These results reveal a conserved role for Gga proteins in regulating phosphatidylinositol 4-kinase function at the TGN.
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Affiliation(s)
- Lydia Daboussi
- Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095
| | - Giancarlo Costaguta
- Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095
| | - Razmik Ghukasyan
- Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095
| | - Gregory S Payne
- Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095
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83
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Altan-Bonnet N. Lipid Tales of Viral Replication and Transmission. Trends Cell Biol 2017; 27:201-213. [PMID: 27838086 PMCID: PMC5318230 DOI: 10.1016/j.tcb.2016.09.011] [Citation(s) in RCA: 108] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2016] [Revised: 09/26/2016] [Accepted: 09/29/2016] [Indexed: 12/22/2022]
Abstract
Positive-strand RNA viruses are the largest group of RNA viruses on Earth and cellular membranes are critical for all aspects of their life cycle, from entry and replication to exit. In particular, membranes serve as platforms for replication and as carriers to transmit these viruses to other cells, the latter either as an envelope surrounding a single virus or as the vesicle containing a population of viruses. Notably, many animal and human viruses appear to induce and exploit phosphatidylinositol 4-phosphate/cholesterol-enriched membranes for replication, whereas many plant and insect-vectored animal viruses utilize phosphatidylethanolamine/cholesterol-enriched membranes for the same purpose; and phosphatidylserine-enriched membrane carriers are widely used by both single and populations of viruses for transmission. Here I discuss the implications for viral pathogenesis and therapeutic development of this remarkable convergence on specific membrane lipid blueprints for replication and transmission.
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Affiliation(s)
- Nihal Altan-Bonnet
- Laboratory of Host-Pathogen Dynamics, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
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84
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Rajkhowa S, Borah SM, Jha AN, Deka RC. Design of Plasmodium falciparum PI(4)KIIIβ Inhibitor using Molecular Dynamics and Molecular Docking Methods. ChemistrySelect 2017. [DOI: 10.1002/slct.201601052] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Sanchaita Rajkhowa
- Department of Chemical Sciences; Tezpur University, Napaam; Tezpur - 784028, Assam India
| | - Sapna Mayuri Borah
- Department of Molecular Biology & Biotechnology; Tezpur University, Napaam; Tezpur - 784028, Assam India
| | - Anupam Nath Jha
- Department of Molecular Biology & Biotechnology; Tezpur University, Napaam; Tezpur - 784028, Assam India
| | - Ramesh Chandra Deka
- Department of Chemical Sciences; Tezpur University, Napaam; Tezpur - 784028, Assam India
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85
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Tassini S, Sun L, Lanko K, Crespan E, Langron E, Falchi F, Kissova M, Armijos-Rivera JI, Delang L, Mirabelli C, Neyts J, Pieroni M, Cavalli A, Costantino G, Maga G, Vergani P, Leyssen P, Radi M. Discovery of Multitarget Agents Active as Broad-Spectrum Antivirals and Correctors of Cystic Fibrosis Transmembrane Conductance Regulator for Associated Pulmonary Diseases. J Med Chem 2017; 60:1400-1416. [DOI: 10.1021/acs.jmedchem.6b01521] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Sabrina Tassini
- P4T Group, Dipartimento
di Scienze degli Alimenti e del Farmaco, Università degli Studi di Parma, Viale delle Scienze, 27/A, 43124 Parma, Italy
| | - Liang Sun
- Laboratory
of Virology and Experimental Chemotherapy, Rega Institute for Medical Research, KU Leuven, Minderbroedersstraat 10, 3000, Leuven, Belgium
| | - Kristina Lanko
- Laboratory
of Virology and Experimental Chemotherapy, Rega Institute for Medical Research, KU Leuven, Minderbroedersstraat 10, 3000, Leuven, Belgium
| | - Emmanuele Crespan
- Istituto di Genetica Molecolare, IGM-CNR, Via Abbiategrasso 207, 27100 Pavia, Italy
| | - Emily Langron
- Department of Neuroscience, Physiology and Pharmacology, University College London, Gower Street, WC1E
6BT London, U.K
| | - Federico Falchi
- CompuNet, Istituto Italiano di Tecnologia, Via Morego 30, I-16163 Genova, Italy
- Department of Pharmacy
and Biotechnology, University of Bologna, Via Belmeloro 6, I-40126 Bologna, Italy
| | - Miroslava Kissova
- Istituto di Genetica Molecolare, IGM-CNR, Via Abbiategrasso 207, 27100 Pavia, Italy
| | | | - Leen Delang
- Laboratory
of Virology and Experimental Chemotherapy, Rega Institute for Medical Research, KU Leuven, Minderbroedersstraat 10, 3000, Leuven, Belgium
| | - Carmen Mirabelli
- Laboratory
of Virology and Experimental Chemotherapy, Rega Institute for Medical Research, KU Leuven, Minderbroedersstraat 10, 3000, Leuven, Belgium
| | - Johan Neyts
- Laboratory
of Virology and Experimental Chemotherapy, Rega Institute for Medical Research, KU Leuven, Minderbroedersstraat 10, 3000, Leuven, Belgium
| | - Marco Pieroni
- P4T Group, Dipartimento
di Scienze degli Alimenti e del Farmaco, Università degli Studi di Parma, Viale delle Scienze, 27/A, 43124 Parma, Italy
| | - Andrea Cavalli
- CompuNet, Istituto Italiano di Tecnologia, Via Morego 30, I-16163 Genova, Italy
- Department of Pharmacy
and Biotechnology, University of Bologna, Via Belmeloro 6, I-40126 Bologna, Italy
| | - Gabriele Costantino
- P4T Group, Dipartimento
di Scienze degli Alimenti e del Farmaco, Università degli Studi di Parma, Viale delle Scienze, 27/A, 43124 Parma, Italy
| | - Giovanni Maga
- Istituto di Genetica Molecolare, IGM-CNR, Via Abbiategrasso 207, 27100 Pavia, Italy
| | - Paola Vergani
- Department of Neuroscience, Physiology and Pharmacology, University College London, Gower Street, WC1E
6BT London, U.K
| | - Pieter Leyssen
- Laboratory
of Virology and Experimental Chemotherapy, Rega Institute for Medical Research, KU Leuven, Minderbroedersstraat 10, 3000, Leuven, Belgium
| | - Marco Radi
- P4T Group, Dipartimento
di Scienze degli Alimenti e del Farmaco, Università degli Studi di Parma, Viale delle Scienze, 27/A, 43124 Parma, Italy
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86
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Humpolickova J, Mejdrová I, Matousova M, Nencka R, Boura E. Fluorescent Inhibitors as Tools To Characterize Enzymes: Case Study of the Lipid Kinase Phosphatidylinositol 4-Kinase IIIβ (PI4KB). J Med Chem 2016; 60:119-127. [PMID: 28004946 DOI: 10.1021/acs.jmedchem.6b01466] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The lipid kinase phosphatidylinositol 4-kinase IIIβ (PI4KB) is an essential host factor for many positive-sense single-stranded RNA (+RNA) viruses including human pathogens hepatitis C virus (HCV), Severe acute respiratory syndrome (SARS), coxsackie viruses, and rhinoviruses. Inhibitors of PI4KB are considered to be potential broad-spectrum virostatics, and it is therefore critical to develop a biochemical understanding of the kinase. Here, we present highly potent and selective fluorescent inhibitors that we show to be useful chemical biology tools especially in determination of dissociation constants. Moreover, we show that the coumarin-labeled inhibitor can be used to image PI4KB in cells using fluorescence-lifetime imaging microscopy (FLIM) microscopy.
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Affiliation(s)
- Jana Humpolickova
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i , Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Ivana Mejdrová
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i , Flemingovo nám. 2, 166 10 Prague 6, Czech Republic.,Department of Chemistry of Natural Compounds, Institute of Chemical Technology Prague , Technicka 5, Prague 166 28, Czech Republic
| | - Marika Matousova
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i , Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Radim Nencka
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i , Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Evzen Boura
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i , Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
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87
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Mejdrová I, Chalupská D, Plačková P, Müller C, Šála M, Klíma M, Baumlová A, Hřebabecký H, Procházková E, Dejmek M, Strunin D, Weber J, Lee G, Matoušová M, Mertlíková-Kaiserová H, Ziebuhr J, Birkus G, Boura E, Nencka R. Rational Design of Novel Highly Potent and Selective Phosphatidylinositol 4-Kinase IIIβ (PI4KB) Inhibitors as Broad-Spectrum Antiviral Agents and Tools for Chemical Biology. J Med Chem 2016; 60:100-118. [PMID: 28004945 DOI: 10.1021/acs.jmedchem.6b01465] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Phosphatidylinositol 4-kinase IIIβ (PI4KB) is indispensable for the replication of various positive-sense single stranded RNA viruses, which hijack this cellular enzyme to remodel intracellular membranes of infected cells to set up the functional replication machinery. Therefore, the inhibition of this PI4K isoform leads to the arrest of viral replication. Here, we report on the synthesis of novel PI4KB inhibitors, which were rationally designed based on two distinct structural types of inhibitors that bind in the ATP binding side of PI4KB. These "hybrids" not only excel in outstanding inhibitory activity but also show high selectivity to PI4KB compared to other kinases. Thus, these compounds exert selective nanomolar or even subnanomolar activity against PI4KB as well as profound antiviral effect against hepatitis C virus, human rhinovirus, and coxsackievirus B3. Our crystallographic analysis unveiled the exact position of the side chains and explains their extensive contribution to the inhibitory activity.
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Affiliation(s)
- Ivana Mejdrová
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i, Gilead Sciences & IOCB Research Centre , Flemingovo nám. 2, 166 10 Prague 6, Czech Republic.,Department of Chemistry of Natural Compounds, Institute of Chemical Technology Prague , Technická 5, Prague 166 28, Czech Republic
| | - Dominika Chalupská
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i, Gilead Sciences & IOCB Research Centre , Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Pavla Plačková
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i, Gilead Sciences & IOCB Research Centre , Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Christin Müller
- Institute of Medical Virology, Justus Liebig University Giessen , Schubertstrasse 81, D-35392 Giessen, Germany
| | - Michal Šála
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i, Gilead Sciences & IOCB Research Centre , Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Martin Klíma
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i, Gilead Sciences & IOCB Research Centre , Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Adriana Baumlová
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i, Gilead Sciences & IOCB Research Centre , Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Hubert Hřebabecký
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i, Gilead Sciences & IOCB Research Centre , Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Eliška Procházková
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i, Gilead Sciences & IOCB Research Centre , Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Milan Dejmek
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i, Gilead Sciences & IOCB Research Centre , Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Dmytro Strunin
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i, Gilead Sciences & IOCB Research Centre , Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Jan Weber
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i, Gilead Sciences & IOCB Research Centre , Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Gary Lee
- Department of Chemistry of Natural Compounds, Institute of Chemical Technology Prague , Technická 5, Prague 166 28, Czech Republic
| | - Marika Matoušová
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i, Gilead Sciences & IOCB Research Centre , Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Helena Mertlíková-Kaiserová
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i, Gilead Sciences & IOCB Research Centre , Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - John Ziebuhr
- Institute of Medical Virology, Justus Liebig University Giessen , Schubertstrasse 81, D-35392 Giessen, Germany
| | - Gabriel Birkus
- Gilead Sciences, Inc. , 333 Lakeside Drive, Foster City, California 94404, United States
| | - Evzen Boura
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i, Gilead Sciences & IOCB Research Centre , Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Radim Nencka
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i, Gilead Sciences & IOCB Research Centre , Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
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88
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McPhail JA, Ottosen EH, Jenkins ML, Burke JE. The Molecular Basis of Aichi Virus 3A Protein Activation of Phosphatidylinositol 4 Kinase IIIβ, PI4KB, through ACBD3. Structure 2016; 25:121-131. [PMID: 27989622 DOI: 10.1016/j.str.2016.11.016] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Revised: 10/19/2016] [Accepted: 11/18/2016] [Indexed: 01/12/2023]
Abstract
Phosphatidylinositol 4-kinase III beta (PI4KIIIβ) is an essential enzyme in mediating membrane transport, and plays key roles in facilitating viral infection. Many pathogenic positive-sense single-stranded RNA viruses activate PI4KIIIβ to generate phosphatidylinositol 4-phosphate (PI4P)-enriched organelles for viral replication. The molecular basis for PI4KIIIβ activation during viral infection has remained largely unclear. We describe the biochemical reconstitution and characterization of the complex of PI4KIIIβ with the Golgi protein Acyl-coenzyme A binding domain containing protein 3 (ACBD3) and Aichi virus 3A protein on membranes. We find that 3A directly activates PI4KIIIβ, and this activation is sensitized by ACBD3. The interfaces between PI4KIIIβ-ACBD3 and ACBD3-3A were mapped with hydrogen-deuterium exchange mass spectrometry (HDX-MS). Determination of the crystal structure of the ACBD3 GOLD domain revealed a unique N terminus that mediates the interaction with 3A. Rationally designed complex-disrupting mutations in both ACBD3 and PI4KIIIβ completely abrogated the sensitization of 3A activation by ACBD3.
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Affiliation(s)
- Jacob A McPhail
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC V8P 5C2, Canada
| | - Erik H Ottosen
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC V8P 5C2, Canada
| | - Meredith L Jenkins
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC V8P 5C2, Canada
| | - John E Burke
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC V8P 5C2, Canada.
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89
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Modulation of membrane phosphoinositide dynamics by the phosphatidylinositide 4-kinase activity of the Legionella LepB effector. Nat Microbiol 2016; 2:16236. [PMID: 27941800 DOI: 10.1038/nmicrobiol.2016.236] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Accepted: 10/07/2016] [Indexed: 11/08/2022]
Abstract
Legionella pneumophila, the causative bacterium for Legionnaires' disease, hijacks host membrane trafficking for the maturation of the Legionella-containing vacuole (LCV). The LCV membrane mainly contains PtdIns4P, which is important for anchoring many secreted Legionella effectors onto the LCV. Here, we identify a cryptic functional domain (LepB_NTD) preceding the well-characterized RabGAP domain in the Legionella Dot/Icm type IV secretion system effector LepB. LepB_NTD alone is toxic to yeast and can disrupt the Golgi in mammalian cells. The crystal structure reveals an unexpected kinase fold and catalytic motif important for LepB_NTD function in eukaryotes. Cell biology-guided biochemical analyses uncovered a lipid kinase activity in LepB_NTD that specifically converts PtdIns3P into PtdIns(3,4)P2. PtdIns(3,4)P2 is efficiently hydrolysed into PtdIns4P by another Dot/Icm effector SidF that is known to possess phosphoinositide phosphatase activity. Consistently, SidF is capable of counteracting the cellular functions of LepB_NTD. Genetic analyses show a requirement for LepB kinase activity as well as lipid phosphatase activity of SidF for PtdIns4P biosynthesis on the LCV membrane. Our study identifies an unprecedented phosphatidylinositide 4-kinase activity from bacteria and highlights a sophisticated manipulation of host phosphoinositide metabolism by a bacterial pathogen.
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90
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Vadas O, Jenkins ML, Dornan GL, Burke JE. Using Hydrogen-Deuterium Exchange Mass Spectrometry to Examine Protein-Membrane Interactions. Methods Enzymol 2016; 583:143-172. [PMID: 28063489 DOI: 10.1016/bs.mie.2016.09.008] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Many fundamental cellular processes are controlled via assembly of a network of proteins at membrane surfaces. The proper recruitment of proteins to membranes can be controlled by a wide variety of mechanisms, including protein lipidation, protein-protein interactions, posttranslational modifications, and binding to specific lipid species present in membranes. There are, however, only a limited number of analytical techniques that can study the assembly of protein-membrane complexes at the molecular level. A relatively new addition to the set of techniques available to study these protein-membrane systems is the use of hydrogen-deuterium exchange mass spectrometry (HDX-MS). HDX-MS experiments measure protein conformational dynamics in their native state, based on the rate of exchange of amide hydrogens with solvent. This review discusses the use of HDX-MS as a tool to identify the interfaces of proteins with membranes and membrane-associated proteins, as well as define conformational changes elicited by membrane recruitment. Specific examples will focus on the use of HDX-MS to examine how large macromolecular protein complexes are recruited and activated on membranes, and how both posttranslational modifications and cancer-linked oncogenic mutations affect these processes.
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Affiliation(s)
- O Vadas
- Pharmaceutical Sciences Section, University of Geneva, Geneva, Switzerland
| | | | - G L Dornan
- University of Victoria, Victoria BC, Canada
| | - J E Burke
- University of Victoria, Victoria BC, Canada.
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91
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Rab11 and phosphoinositides: A synergy of signal transducers in the control of vesicular trafficking. Adv Biol Regul 2016; 63:132-139. [PMID: 27658318 DOI: 10.1016/j.jbior.2016.09.002] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Accepted: 09/13/2016] [Indexed: 12/11/2022]
Abstract
Rab11 and phosphoinositides are signal transducers able to direct the delivery of membrane components to the cell surface. Rab11 is a small GTPase that, by cycling from an active to an inactive state, controls key events of vesicular transport, while phosphoinositides are major determinants of membrane identity, modulating compartmentalized small GTPase function. By sharing common effectors, these two signal transducers synergistically direct vesicular traffic to specific intracellular membranes. This review focuses on the latest advances regarding the mechanisms that ensure the compartmentalized regulation of Rab11 function through its interaction with phosphoinositides.
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92
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Diversity-oriented synthesis yields novel multistage antimalarial inhibitors. Nature 2016; 538:344-349. [PMID: 27602946 DOI: 10.1038/nature19804] [Citation(s) in RCA: 203] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Accepted: 08/31/2016] [Indexed: 02/08/2023]
Abstract
Antimalarial drugs have thus far been chiefly derived from two sources-natural products and synthetic drug-like compounds. Here we investigate whether antimalarial agents with novel mechanisms of action could be discovered using a diverse collection of synthetic compounds that have three-dimensional features reminiscent of natural products and are underrepresented in typical screening collections. We report the identification of such compounds with both previously reported and undescribed mechanisms of action, including a series of bicyclic azetidines that inhibit a new antimalarial target, phenylalanyl-tRNA synthetase. These molecules are curative in mice at a single, low dose and show activity against all parasite life stages in multiple in vivo efficacy models. Our findings identify bicyclic azetidines with the potential to both cure and prevent transmission of the disease as well as protect at-risk populations with a single oral dose, highlighting the strength of diversity-oriented synthesis in revealing promising therapeutic targets.
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93
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Probing the dynamic regulation of peripheral membrane proteins using hydrogen deuterium exchange-MS (HDX-MS). Biochem Soc Trans 2016; 43:773-86. [PMID: 26517882 DOI: 10.1042/bst20150065] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Many cellular signalling events are controlled by the selective recruitment of protein complexes to membranes. Determining the molecular basis for how lipid signalling complexes are recruited, assembled and regulated on specific membrane compartments has remained challenging due to the difficulty of working in conditions mimicking native biological membrane environments. Enzyme recruitment to membranes is controlled by a variety of regulatory mechanisms, including binding to specific lipid species, protein-protein interactions, membrane curvature, as well as post-translational modifications. A powerful tool to study the regulation of membrane signalling enzymes and complexes is hydrogen deuterium exchange-MS (HDX-MS), a technique that allows for the interrogation of protein dynamics upon membrane binding and recruitment. This review will highlight the theory and development of HDX-MS and its application to examine the molecular basis of lipid signalling enzymes, specifically the regulation and activation of phosphoinositide 3-kinases (PI3Ks).
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94
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Baumlova A, Gregor J, Boura E. The structural basis for calcium inhibition of lipid kinase PI4K IIalpha and comparison with the apo state. Physiol Res 2016; 65:987-993. [PMID: 27539108 DOI: 10.33549/physiolres.933344] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
PI4K IIalpha is a critical enzyme for the maintenance of Golgi and is also known to function in the synaptic vesicles. The product of its catalytical function, phosphatidylinositol 4-phosphate (PI4P), is an important lipid molecule because it is a hallmark of the Golgi and TGN, is directly recognized by many proteins and also serves as a precursor molecule for synthesis of higher phosphoinositides. Here, we report crystal structures of PI4K IIalpha enzyme in the apo-state and inhibited by calcium. The apo-structure reveals a surprising rigidity of the active site residues important for catalytic activity. The structure of calcium inhibited kinase reveals how calcium locks ATP in the active site.
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Affiliation(s)
- A Baumlova
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Prague, Czech Republic.
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95
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Ren JX, Gao NN, Cao XS, Hu QA, Xie Y. Homology modeling and virtual screening for inhibitors of lipid kinase PI(4)K from Plasmodium. Biomed Pharmacother 2016; 83:798-808. [PMID: 27490781 DOI: 10.1016/j.biopha.2016.07.048] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Revised: 07/14/2016] [Accepted: 07/24/2016] [Indexed: 11/27/2022] Open
Abstract
Malaria parasite strains have emerged to tolerate the therapeutic effects of the prophylactics and drugs presently available. Recent studies have shown that KAI715 and its analogs inhibit malaria parasites growth by binding to lipid kinase PI(4)K (phosphatidylinositol-4-OH kinase) of the parasites. Therefore, targeting PI(4)K may open up new avenues of target-based drug discovery to identify novel anti-malaria drugs. In this investigation, we describe the discovery of novel potent PfPI(4)K (PI(4)K from P. falciparum) inhibitors by employing a proposed hybrid virtual screening (VS) method, including pharmacophore model, drug-likeness prediction and molecular docking approach. 3D structure of PfPI(4)K has been established by homology modeling. Pharmacophore model HypoA of PfPI(4)K inhibitors has been developed based on the ligand complexed with its corresponding receptor. 174 compounds with good ADMET properties were carefully selected by a hybrid virtual screening method. Finally, the 174 hits were further validated by using a new pharmacophore model HypoB built based on the docking pose of BQR685, and 95 compounds passed the last filter. These compounds would be further evaluated by biological activity assays. The molecular interactions of the top two potential inhibitors with the active site residues are discussed in detail. These identified hits can be further used for designing the more potent inhibitors against PfPI(4)K by scaffold hopping, and deserve consideration for further structure-activity relationship (SAR) studies.
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Affiliation(s)
- Ji-Xia Ren
- College of Life Science, Liaocheng University, Liaocheng 252059, People's Republic of China; Institute of Medicinal Plant Development, Chinese Academy of Medical Science & Peking Union Medical College, 151 Malianwa North Road, Haidian District, Beijing 100193, People's Republic of China
| | - Na-Na Gao
- Central Laboratory, Beijing Shijitan Hospital Affiliated to Capital Medical University, Beijing 100038, People's Republic of China
| | - Xue-Song Cao
- College of Life Science, Liaocheng University, Liaocheng 252059, People's Republic of China
| | - Quan-An Hu
- College of Life Science, Liaocheng University, Liaocheng 252059, People's Republic of China
| | - Yong Xie
- Institute of Medicinal Plant Development, Chinese Academy of Medical Science & Peking Union Medical College, 151 Malianwa North Road, Haidian District, Beijing 100193, People's Republic of China.
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96
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Šála M, Kögler M, Plačková P, Mejdrová I, Hřebabecký H, Procházková E, Strunin D, Lee G, Birkus G, Weber J, Mertlíková-Kaiserová H, Nencka R. Purine analogs as phosphatidylinositol 4-kinase IIIβ inhibitors. Bioorg Med Chem Lett 2016; 26:2706-12. [PMID: 27090557 PMCID: PMC7127540 DOI: 10.1016/j.bmcl.2016.04.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Revised: 04/01/2016] [Accepted: 04/03/2016] [Indexed: 11/29/2022]
Abstract
We report on an extensive structure-activity relationship study of novel PI4K IIIβ inhibitors. The purine derivative of the potent screening hit T-00127-HEV1 has served as a suitable starting point for a thorough investigation of positions 8 and 2. While position 8 of the purine scaffold can only bear a small substituent to maintain the inhibitory activity, position 2 is opened for extensive modification and can accommodate even substituted phenyl rings without the loss of PI4K IIIβ inhibitory activity. These empirical observations nicely correlate with the results of our docking study, which suggests that position 2 directs towards solution and can provide the necessary space for the interaction with remote residues of the enzyme, whereas the cavity around position 8 is strictly limited. The obtained compounds have also been subjected to antiviral screening against a panel of (+)ssRNA viruses.
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Affiliation(s)
- Michal Šála
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i, Gilead Sciences & IOCB Research Centre, Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Martin Kögler
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i, Gilead Sciences & IOCB Research Centre, Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Pavla Plačková
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i, Gilead Sciences & IOCB Research Centre, Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Ivana Mejdrová
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i, Gilead Sciences & IOCB Research Centre, Flemingovo nám. 2, 166 10 Prague 6, Czech Republic; Department of Chemistry of Natural Compounds, Institute of Chemical Technology Prague, Technická 5, Prague 166 28, Czech Republic
| | - Hubert Hřebabecký
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i, Gilead Sciences & IOCB Research Centre, Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Eliška Procházková
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i, Gilead Sciences & IOCB Research Centre, Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Dmytro Strunin
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i, Gilead Sciences & IOCB Research Centre, Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Gary Lee
- Gilead Sciences, Inc., 333 Lakeside Drive, Foster City, CA 94404, United States
| | - Gabriel Birkus
- Gilead Sciences, Inc., 333 Lakeside Drive, Foster City, CA 94404, United States
| | - Jan Weber
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i, Gilead Sciences & IOCB Research Centre, Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Helena Mertlíková-Kaiserová
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i, Gilead Sciences & IOCB Research Centre, Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Radim Nencka
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i, Gilead Sciences & IOCB Research Centre, Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
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97
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Structural insights and in vitro reconstitution of membrane targeting and activation of human PI4KB by the ACBD3 protein. Sci Rep 2016; 6:23641. [PMID: 27009356 PMCID: PMC4806292 DOI: 10.1038/srep23641] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 03/10/2016] [Indexed: 11/09/2022] Open
Abstract
Phosphatidylinositol 4-kinase beta (PI4KB) is one of four human PI4K enzymes that generate phosphatidylinositol 4-phosphate (PI4P), a minor but essential regulatory lipid found in all eukaryotic cells. To convert their lipid substrates, PI4Ks must be recruited to the correct membrane compartment. PI4KB is critical for the maintenance of the Golgi and trans Golgi network (TGN) PI4P pools, however, the actual targeting mechanism of PI4KB to the Golgi and TGN membranes is unknown. Here, we present an NMR structure of the complex of PI4KB and its interacting partner, Golgi adaptor protein acyl-coenzyme A binding domain containing protein 3 (ACBD3). We show that ACBD3 is capable of recruiting PI4KB to membranes both in vitro and in vivo, and that membrane recruitment of PI4KB by ACBD3 increases its enzymatic activity and that the ACBD3:PI4KB complex formation is essential for proper function of the Golgi.
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98
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Abstract
Many viruses exploit specific arms of the endomembrane system. The unique composition of each arm prompts the development of remarkably specific interactions between viruses and sub-organelles. This review focuses on the viral–host interactions occurring on the endocytic recycling compartment (ERC), and mediated by its regulatory Ras-related in brain (Rab) GTPase Rab11. This protein regulates trafficking from the ERC and the trans-Golgi network to the plasma membrane. Such transport comprises intricate networks of proteins/lipids operating sequentially from the membrane of origin up to the cell surface. Rab11 is also emerging as a critical factor in an increasing number of infections by major animal viruses, including pathogens that provoke human disease. Understanding the interplay between the ERC and viruses is a milestone in human health. Rab11 has been associated with several steps of the viral lifecycles by unclear processes that use sophisticated diversified host machinery. For this reason, we first explore the state-of-the-art on processes regulating membrane composition and trafficking. Subsequently, this review outlines viral interactions with the ERC, highlighting current knowledge on viral-host binding partners. Finally, using examples from the few mechanistic studies available we emphasize how ERC functions are adjusted during infection to remodel cytoskeleton dynamics, innate immunity and membrane composition.
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Affiliation(s)
- Sílvia Vale-Costa
- Cell Biology of Viral Infection Lab, Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal.
| | - Maria João Amorim
- Cell Biology of Viral Infection Lab, Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal.
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99
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Rutaganira FU, Fowler ML, McPhail JA, Gelman MA, Nguyen K, Xiong A, Dornan GL, Tavshanjian B, Glenn JS, Shokat KM, Burke JE. Design and Structural Characterization of Potent and Selective Inhibitors of Phosphatidylinositol 4 Kinase IIIβ. J Med Chem 2016; 59:1830-9. [PMID: 26885694 DOI: 10.1021/acs.jmedchem.5b01311] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Type III phosphatidylinositol 4-kinase (PI4KIIIβ) is an essential enzyme in mediating membrane trafficking and is implicated in a variety of pathogenic processes. It is a key host factor mediating replication of RNA viruses. The design of potent and specific inhibitors of this enzyme will be essential to define its cellular roles and may lead to novel antiviral therapeutics. We previously reported the PI4K inhibitor PIK93, and this compound has defined key functions of PI4KIIIβ. However, this compound showed high cross reactivity with class I and III PI3Ks. Using structure-based drug design, we have designed novel potent and selective (>1000-fold over class I and class III PI3Ks) PI4KIIIβ inhibitors. These compounds showed antiviral activity against hepatitis C virus. The co-crystal structure of PI4KIIIβ bound to one of the most potent compounds reveals the molecular basis of specificity. This work will be vital in the design of novel PI4KIIIβ inhibitors, which may play significant roles as antiviral therapeutics.
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Affiliation(s)
- Florentine U Rutaganira
- Howard Hughes Medical Institute and Department of Cellular and Molecular Pharmacology, University of California, San Francisco (UCSF) , San Francisco, California 94143, United States
| | - Melissa L Fowler
- Department of Biochemistry and Microbiology, University of Victoria , Victoria, BC V8W 2Y2, Canada
| | - Jacob A McPhail
- Department of Biochemistry and Microbiology, University of Victoria , Victoria, BC V8W 2Y2, Canada
| | - Michael A Gelman
- Department of Medicine and Department of Microbiology & Immunology, Stanford University , Palo Alto, California 94305, United States
| | - Khanh Nguyen
- Department of Medicine and Department of Microbiology & Immunology, Stanford University , Palo Alto, California 94305, United States
| | - Anming Xiong
- Department of Medicine and Department of Microbiology & Immunology, Stanford University , Palo Alto, California 94305, United States
| | - Gillian L Dornan
- Department of Biochemistry and Microbiology, University of Victoria , Victoria, BC V8W 2Y2, Canada
| | - Brandon Tavshanjian
- Howard Hughes Medical Institute and Department of Cellular and Molecular Pharmacology, University of California, San Francisco (UCSF) , San Francisco, California 94143, United States
| | - Jeffrey S Glenn
- Department of Medicine and Department of Microbiology & Immunology, Stanford University , Palo Alto, California 94305, United States.,Veterans Administration Medical Center , Palo Alto, California 94304, United States
| | - Kevan M Shokat
- Howard Hughes Medical Institute and Department of Cellular and Molecular Pharmacology, University of California, San Francisco (UCSF) , San Francisco, California 94143, United States
| | - John E Burke
- Department of Biochemistry and Microbiology, University of Victoria , Victoria, BC V8W 2Y2, Canada
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100
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Type III phosphatidylinositol 4 kinases: structure, function, regulation, signalling and involvement in disease. Biochem Soc Trans 2016; 44:260-6. [DOI: 10.1042/bst20150219] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Many important cellular functions are regulated by the selective recruitment of proteins to intracellular membranes mediated by specific interactions with lipid phosphoinositides. The enzymes that generate lipid phosphoinositides therefore must be properly positioned and regulated at their correct cellular locations. Phosphatidylinositol 4 kinases (PI4Ks) are key lipid signalling enzymes, and they generate the lipid species phosphatidylinositol 4-phosphate (PI4P), which plays important roles in regulating physiological processes including membrane trafficking, cytokinesis and organelle identity. PI4P also acts as the substrate for the generation of the signalling phosphoinositides phosphatidylinositol 4,5-bisphosphate (PIP2) and phosphatidylinositol 3,4,5-trisphosphate (PIP3). PI4Ks also play critical roles in a number of pathological processes including mediating replication of a number of pathogenic RNA viruses, and in the development of the parasite responsible for malaria. Key to the regulation of PI4Ks is their regulation by a variety of both host and viral protein-binding partners. We review herein our current understanding of the structure, regulatory interactions and role in disease of the type III PI4Ks.
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