201
|
ATX and LPA receptor 3 are coordinately up-regulated in lipopolysaccharide-stimulated THP-1 cells through PKR and SPK1-mediated pathways. FEBS Lett 2012; 586:792-7. [DOI: 10.1016/j.febslet.2012.01.044] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2011] [Revised: 12/30/2011] [Accepted: 01/20/2012] [Indexed: 02/07/2023]
|
202
|
Elliott TS, Slowey A, Ye Y, Conway SJ. The use of phosphate bioisosteres in medicinal chemistry and chemical biology. MEDCHEMCOMM 2012. [DOI: 10.1039/c2md20079a] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
|
203
|
Parrill AL, Wanjala IW, Pham TCT, Baker DL. Computational identification and experimental characterization of substrate binding determinants of nucleotide pyrophosphatase/phosphodiesterase 7. BMC BIOCHEMISTRY 2011; 12:65. [PMID: 22177013 PMCID: PMC3282672 DOI: 10.1186/1471-2091-12-65] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/14/2011] [Accepted: 12/16/2011] [Indexed: 11/10/2022]
Abstract
BACKGROUND Nucleotide pyrophosphatase/phosphodiesterase 7 (NPP7) is the only member of the mammalian NPP enzyme family that has been confirmed to act as a sphingomyelinase, hydrolyzing sphingomyelin (SM) to form phosphocholine and ceramide. NPP7 additionally hydrolyzes lysophosphatidylcholine (LPC), a substrate preference shared with the NPP2/autotaxin(ATX) and NPP6 mammalian family members. This study utilizes a synergistic combination of molecular modeling validated by experimental site-directed mutagenesis to explore the molecular basis for the unique ability of NPP7 to hydrolyze SM. RESULTS The catalytic function of NPP7 against SM, LPC, platelet activating factor (PAF) and para-nitrophenylphosphorylcholine (pNPPC) is impaired in the F275A mutant relative to wild type NPP7, but different impacts are noted for mutations at other sites. These results are consistent with a previously described role of F275 to interact with the choline headgroup, where all substrates share a common functionality. The L107F mutation showed enhanced hydrolysis of LPC, PAF and pNPPC but reduced hydrolysis of SM. Modeling suggests this difference can be explained by the gain of cation-pi interactions with the choline headgroups of all four substrates, opposed by increased steric crowding against the sphingoid tail of SM. Modeling also revealed that the long and flexible hydrophobic tails of substrates exhibit considerable dynamic flexibility in the binding pocket, reducing the entropic penalty that might otherwise be incurred upon substrate binding. CONCLUSIONS Substrate recognition by NPP7 includes several important contributions, ranging from cation-pi interactions between F275 and the choline headgroup of all substrates, to tail-group binding pockets that accommodate the inherent flexibility of the lipid hydrophobic tails. Two contributions to the unique ability of NPP7 to hydrolyze SM were identified. First, the second hydrophobic tail of SM occupies a second hydrophobic binding pocket. Second, the leucine residue present at position 107 contrasts with a conserved phenylalanine in NPP enzymes that do not utilize SM as a substrate, consistent with the observed reduction in SM hydrolysis by the NPP7-L107F mutant.
Collapse
Affiliation(s)
- Abby L Parrill
- Department of Chemistry and the Computational Research on Materials Institute, The University of Memphis, Memphis, TN 38152, USA.
| | | | | | | |
Collapse
|
204
|
Dennis J, Morgan MK, Graf MR, Fuss B. P2Y12 receptor expression is a critical determinant of functional responsiveness to ATX's MORFO domain. Purinergic Signal 2011; 8:181-90. [PMID: 22139091 DOI: 10.1007/s11302-011-9283-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2011] [Accepted: 11/11/2011] [Indexed: 01/13/2023] Open
Abstract
In the central nervous system, the formation of the myelin sheath and the differentiation of the myelinating cells, namely oligodendrocytes, are regulated by complex signaling networks that involve purinergic receptors and the extracellular matrix. However, the exact nature of the molecular interactions underlying these networks still needs to be defined. In this respect, the data presented here reveal a signaling mechanism that is characterized by an interaction between the purinergic P2Y(12) receptor and the matricellular extracellular matrix protein autotaxin (ATX), also known as ENPP2, phosphodiesterase-Iα/ATX, or lysoPLD. ATX has been previously described by us to mediate intermediate states of oligodendrocyte adhesion and to enable changes in oligodendrocyte morphology that are thought to be crucial for the formation of a fully functional myelin sheath. This functional property of ATX is mediated by ATX's modulator of oligodendrocyte remodeling and focal adhesion organization (MORFO) domain. Here, we show that the expression of the P2Y(12) receptor is necessary for ATX's MORFO domain to exert its effects on differentiating oligodendrocytes. In addition, our data demonstrate that exogenous expression of the P2Y(12) receptor can render cells responsive to the known effects of ATX's MORFO domain, and they identify Rac1 as an intracellular factor mediating the effect of ATX-MORFO-P2Y(12) signaling on the assembly of focal adhesions. Our data further support the idea that a physical interaction between ATX and the P2Y(12) receptor provides the basis for an ATX-MORFO-P2Y(12) signaling axis that is crucial for mediating cellular states of intermediate adhesion and morphological/structural plasticity.
Collapse
Affiliation(s)
- Jameel Dennis
- Department of Anatomy, Virginia Commonwealth University Medical Center, Richmond, VA 23298, USA.
| | | | | | | |
Collapse
|
205
|
Lysophosphatidic acid directly activates TRPV1 through a C-terminal binding site. Nat Chem Biol 2011; 8:78-85. [PMID: 22101604 DOI: 10.1038/nchembio.712] [Citation(s) in RCA: 152] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2011] [Accepted: 08/29/2011] [Indexed: 02/07/2023]
Abstract
Since 1992, there has been growing evidence that the bioactive phospholipid lysophosphatidic acid (LPA), whose amounts are increased upon tissue injury, activates primary nociceptors resulting in neuropathic pain. The TRPV1 ion channel is expressed in primary afferent nociceptors and is activated by physical and chemical stimuli. Here we show that in control mice LPA produces acute pain-like behaviors, which are substantially reduced in Trpv1-null animals. Our data also demonstrate that LPA activates TRPV1 through a unique mechanism that is independent of G protein-coupled receptors, contrary to what has been widely shown for other ion channels, by directly interacting with the C terminus of the channel. We conclude that TRPV1 is a direct molecular target of the pain-producing molecule LPA and that this constitutes, to our knowledge, the first example of LPA binding directly to an ion channel to acutely regulate its function.
Collapse
|
206
|
Kryshtafovych A, Moult J, Bartual SG, Bazan JF, Berman H, Casteel DE, Christodoulou E, Everett JK, Hausmann J, Heidebrecht T, Hills T, Hui R, Hunt JF, Seetharaman J, Joachimiak A, Kennedy MA, Kim C, Lingel A, Michalska K, Montelione GT, Otero JM, Perrakis A, Pizarro JC, van Raaij MJ, Ramelot TA, Rousseau F, Tong L, Wernimont AK, Young J, Schwede T. Target highlights in CASP9: Experimental target structures for the critical assessment of techniques for protein structure prediction. Proteins 2011; 79 Suppl 10:6-20. [PMID: 22020785 PMCID: PMC3692002 DOI: 10.1002/prot.23196] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
One goal of the CASP community wide experiment on the critical assessment of techniques for protein structure prediction is to identify the current state of the art in protein structure prediction and modeling. A fundamental principle of CASP is blind prediction on a set of relevant protein targets, that is, the participating computational methods are tested on a common set of experimental target proteins, for which the experimental structures are not known at the time of modeling. Therefore, the CASP experiment would not have been possible without broad support of the experimental protein structural biology community. In this article, several experimental groups discuss the structures of the proteins which they provided as prediction targets for CASP9, highlighting structural and functional peculiarities of these structures: the long tail fiber protein gp37 from bacteriophage T4, the cyclic GMP-dependent protein kinase Iβ dimerization/docking domain, the ectodomain of the JTB (jumping translocation breakpoint) transmembrane receptor, Autotaxin in complex with an inhibitor, the DNA-binding J-binding protein 1 domain essential for biosynthesis and maintenance of DNA base-J (β-D-glucosyl-hydroxymethyluracil) in Trypanosoma and Leishmania, an so far uncharacterized 73 residue domain from Ruminococcus gnavus with a fold typical for PDZ-like domains, a domain from the phycobilisome core-membrane linker phycobiliprotein ApcE from Synechocystis, the heat shock protein 90 activators PFC0360w and PFC0270w from Plasmodium falciparum, and 2-oxo-3-deoxygalactonate kinase from Klebsiella pneumoniae.
Collapse
Affiliation(s)
- Andriy Kryshtafovych
- Genome Center, University of California-Davis, 451 Health Sciences Drive, Davis, CA 95616, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
207
|
Blaho VA, Hla T. Regulation of mammalian physiology, development, and disease by the sphingosine 1-phosphate and lysophosphatidic acid receptors. Chem Rev 2011; 111:6299-320. [PMID: 21939239 PMCID: PMC3216694 DOI: 10.1021/cr200273u] [Citation(s) in RCA: 113] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Victoria A. Blaho
- Center for Vascular Biology, Department of Pathology and Laboratory Medicine, Weill Medical College of Cornell University, New York, NY 10065
| | - Timothy Hla
- Center for Vascular Biology, Department of Pathology and Laboratory Medicine, Weill Medical College of Cornell University, New York, NY 10065
| |
Collapse
|
208
|
Selvy PE, Lavieri RR, Lindsley CW, Brown HA. Phospholipase D: enzymology, functionality, and chemical modulation. Chem Rev 2011; 111:6064-119. [PMID: 21936578 PMCID: PMC3233269 DOI: 10.1021/cr200296t] [Citation(s) in RCA: 251] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Paige E Selvy
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee 37064, USA
| | | | | | | |
Collapse
|
209
|
Hashimoto T, Okudaira S, Igarashi K, Hama K, Yatomi Y, Aoki J. Identification and biochemical characterization of a novel autotaxin isoform, ATXδ, with a four-amino acid deletion. J Biochem 2011; 151:89-97. [PMID: 21994952 DOI: 10.1093/jb/mvr126] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Autotaxin (ATX) is lysophospholipase D, which converts lysophospholipids such as lysophosphatidylcholine (LPC) to lysophosphatidic acid (LPA), a bioactive lipid mediator with multiple biological roles. ATX is present in high concentrations in various biological fluids and is responsible for LPA production in these fluids. The plasma ATX level is altered in some patho-physiological conditions. Three splicing isoforms of ATX have been reported so far (ATXα, β and γ). In this study, we identified and characterized ATXδ, a novel alternative splice variant of ATX, which has a four-amino acid deletion in the L2 linker region of ATXβ. ATXδ was found to be the second major isoform following ATXβ and fully active. ATXβ and ATXδ showed similar divalent cation sensitivity and cell motility-stimulating activity. ATXβ and ATXδ are present in wide range of organism from fish to mammals. Among them, only ATXδ was found in Gallus gallus and Xenopus laevis, suggesting the indispensable role of the isoform. ATXδ was expressed in various human tissues with different expression patterns from that of ATXβ. These results show that ATXδ is a second major ATX isoform sharing similar biochemical characters with the major isoform, ATXβ, and is a potential biomarker.
Collapse
Affiliation(s)
- Takafumi Hashimoto
- Department of Molecular and Cellular Biochemistry, Graduate School of Pharmaceutical Science, Tohoku University, 6-3 Aoba Aramaki, Aoba-ku, Sendai, Miyagi 980-8578, Japan
| | | | | | | | | | | |
Collapse
|
210
|
Mize CD, Abbott AM, Gacasan SB, Parrill AL, Baker DL. Ligand-based autotaxin pharmacophore models reflect structure-based docking results. J Mol Graph Model 2011; 31:76-86. [PMID: 21967734 DOI: 10.1016/j.jmgm.2011.09.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2011] [Revised: 09/03/2011] [Accepted: 09/12/2011] [Indexed: 10/17/2022]
Abstract
The autotaxin (ATX) enzyme exhibits lysophospholipase D activity responsible for the conversion of lysophosphatidyl choline to lysophosphatidic acid (LPA). ATX and LPA have been linked to the initiation of atherosclerosis, cancer invasiveness, and neuropathic pain. ATX inhibition therefore offers currently unexploited therapeutic potential, and substantial interest in the development of ATX inhibitors is evident in the recent literature. Here we report the performance-based comparison of ligand-based pharmacophores developed on the basis of different combinations of ATX inhibitors in the training sets against an extensive database of compounds tested for ATX inhibitory activity, as well as with docking results of the actives against a recently reported ATX crystal structure. In general, pharmacophore models show better ability to select active ATX inhibitors binding in a common location when the ligand-based superposition shows a good match to the superposition of actives based on docking results. Two pharmacophore models developed on the basis of competitive inhibitors in combination with the single inhibitor crystallized to date in the active site of ATX were able to identify actives at rates over 40%, a substantial improvement over the <10% representation of active site-directed actives in the test set database.
Collapse
Affiliation(s)
- Catrina D Mize
- Department of Chemistry, The University of Memphis, Memphis, TN 38152, USA
| | | | | | | | | |
Collapse
|
211
|
Moolenaar WH, Perrakis A. Insights into autotaxin: how to produce and present a lipid mediator. Nat Rev Mol Cell Biol 2011; 12:674-9. [PMID: 21915140 DOI: 10.1038/nrm3188] [Citation(s) in RCA: 135] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Autotaxin (ATX) is a secreted phosphodiesterase that produces the lipid mediator lysophosphatidic acid (LPA). LPA acts through specific guanine-nucleotide-binding protein (G protein)-coupled receptors to stimulate migration, proliferation, survival and other functions in many cell types. ATX is important in vivo for processes as diverse as vasculogenesis, lymphocyte trafficking and tumour progression. However, the inner workings of ATX have long been elusive, in terms of both its substrate specificity and how localized LPA signalling is achieved. Structural studies have shown how ATX recognizes its substrates and may interact with the cell surface to promote specificity in LPA signalling.
Collapse
|
212
|
Jiang G, Madan D, Prestwich GD. Aromatic phosphonates inhibit the lysophospholipase D activity of autotaxin. Bioorg Med Chem Lett 2011; 21:5098-101. [PMID: 21489790 PMCID: PMC3140587 DOI: 10.1016/j.bmcl.2011.03.068] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2011] [Revised: 03/16/2011] [Accepted: 03/17/2011] [Indexed: 11/28/2022]
Abstract
Autotaxin (ATX) is an attractive target for the anticancer therapeutics that inhibits angiogenesis, invasion and migration. ATX is an extracellular lysophospholipase D that hydrolyzes lysophosphatidylcholine to form the bioactive lipid lysophosphatidic acid. The aromatic phosphonate S32826 was the first described nanomolar inhibitor of ATX. However, the tridecylamide substituent on aromatic ring contributed to its poor solubility and bioavailability, severely limiting its utility in vivo. cLogP calculations revealed that the lipophilicity of S32826 could be lowered by shortening its hydrophobic chain and by introducing substituents alpha to the phosphonate. Herein, we describe the synthesis of a small set of α-substituted phosphonate analogs of S32826, and we show that shortening the chain and adding α-halo or α-hydroxy substituents increased solubility; however, ATX inhibition was reduced by most substitutions. An optimal compound was identified for examination of biological effects of ATX inhibition in vivo.
Collapse
Affiliation(s)
- Guowei Jiang
- Department of Medicinal Chemistry, The University of Utah, 419 Wakara Way, Suite 205, Salt Lake City, Utah 84108-1257
| | - Damian Madan
- Echelon Biosciences Inc., 675 Arapeen Way, Suite 302, Salt Lake City, UT 84108
| | - Glenn D. Prestwich
- Department of Medicinal Chemistry, The University of Utah, 419 Wakara Way, Suite 205, Salt Lake City, Utah 84108-1257
| |
Collapse
|
213
|
Saunders LP, Cao W, Chang WC, Albright RA, Braddock DT, De La Cruz EM. Kinetic analysis of autotaxin reveals substrate-specific catalytic pathways and a mechanism for lysophosphatidic acid distribution. J Biol Chem 2011; 286:30130-41. [PMID: 21719699 PMCID: PMC3191052 DOI: 10.1074/jbc.m111.246884] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2011] [Revised: 06/23/2011] [Indexed: 01/28/2023] Open
Abstract
Autotaxin (ATX) is a secreted lysophospholipase D that hydrolyzes lysophosphatidylcholine (LPC) into lysophosphatidic acid (LPA), initiating signaling cascades leading to cancer metastasis, wound healing, and angiogenesis. Knowledge of the pathway and kinetics of LPA synthesis by ATX is critical for developing quantitative physiological models of LPA signaling. We measured the individual rate constants and pathway of the LPA synthase cycle of ATX using the fluorescent lipid substrates FS-3 and 12-(N-methyl-N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl))-LPC. FS-3 binds rapidly (k(1) ≥500 μm(-1) s(-1)) and is hydrolyzed slowly (k(2) = 0.024 s(-1)). Release of the first hydrolysis product is random and rapid (≥1 s(-1)), whereas release of the second is slow and rate-limiting (0.005-0.007 s(-1)). Substrate binding and hydrolysis are slow and rate-limiting with LPC. Product release is sequential with choline preceding LPA. The catalytic pathway and kinetics depend strongly on the substrate, suggesting that ATX kinetics could vary for the various in vivo substrates. Slow catalysis with LPC reveals the potential for LPA signaling to spread to cells distal to the site of LPC substrate binding by ATX. An ATX mutant in which catalytic threonine at position 210 is replaced with alanine binds substrate weakly, favoring a role for Thr-210 in binding as well as catalysis. FTY720P, the bioactive form of a drug currently used to treat multiple sclerosis, inhibits ATX in an uncompetitive manner and slows the hydrolysis reaction, suggesting that ATX inhibition plays a significant role in lymphocyte immobilization in FTY720P-based therapeutics.
Collapse
Affiliation(s)
- Lauren P. Saunders
- From the Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520 and
| | - Wenxiang Cao
- From the Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520 and
| | - William C. Chang
- the Department of Pathology, Yale University School of Medicine, New Haven, Connecticut 06510
| | - Ronald A. Albright
- the Department of Pathology, Yale University School of Medicine, New Haven, Connecticut 06510
| | - Demetrios T. Braddock
- the Department of Pathology, Yale University School of Medicine, New Haven, Connecticut 06510
| | - Enrique M. De La Cruz
- From the Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520 and
| |
Collapse
|
214
|
Fulkerson Z, Wu T, Sunkara M, Kooi CV, Morris AJ, Smyth SS. Binding of autotaxin to integrins localizes lysophosphatidic acid production to platelets and mammalian cells. J Biol Chem 2011; 286:34654-63. [PMID: 21832043 DOI: 10.1074/jbc.m111.276725] [Citation(s) in RCA: 119] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Autotaxin (ATX) is a secreted lysophospholipase D that generates the bioactive lipid mediator lysophosphatidic acid (LPA). We and others have reported that ATX binds to integrins, but the function of ATX-integrin interactions is unknown. The recently reported crystal structure of ATX suggests a role for the solvent-exposed surface of the N-terminal tandem somatomedin B-like domains in binding to platelet integrin αIIbβ(3). The opposite face of the somatomedin B-like domain interacts with the catalytic phosphodiesterase (PDE) domain to form a hydrophobic channel through which lysophospholipid substrates enter and leave the active site. Based on this structure, we hypothesize that integrin-bound ATX can access cell surface substrates and deliver LPA to cell surface receptors. To test this hypothesis, we investigated the integrin selectivity and signaling pathways that promote ATX binding to platelets. We report that both platelet β1 and β3 integrins interact in an activation-dependent manner with ATX via the SMB2 domain. ATX increases thrombin-stimulated LPA production by washed platelets ~10-fold. When incubated under conditions to promote integrin activation, ATX generates LPA from CHO cells primed with bee venom phospholipase A(2), and ATX-mediated LPA production is enhanced more than 2-fold by CHO cell overexpression of integrin β(3). The effects of ATX on platelet and cell-associated LPA production, but not hydrolysis of small molecule or detergent-solubilized substrates, are attenuated by point mutations in the SMB2 that impair integrin binding. Integrin binding therefore localizes ATX activity to the cell surface, providing a mechanism to generate LPA in the vicinity of its receptors.
Collapse
Affiliation(s)
- Zachary Fulkerson
- Division of Cardiovascular Medicine, The Gill Heart Institute, Lexington, KY 40536-0200, USA
| | | | | | | | | | | |
Collapse
|
215
|
X-ray crystallography at the heart of life science. Curr Opin Struct Biol 2011; 21:622-6. [PMID: 21824762 DOI: 10.1016/j.sbi.2011.07.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2011] [Accepted: 07/11/2011] [Indexed: 11/23/2022]
Abstract
X-ray crystallography is the fundamental research tool that shaped our notion on biological structure & function at the molecular level. It generates the information vital to understand life processes by providing the information required for creating accurate three-dimensional models (namely mapping the position of each and every atom that makes up the studied object). The use of this method begun in the middle of last century following Max von Laue discovery of the phenomenon of diffraction of X-rays by crystals, and the successful application of this discovery for the determination of the electronic distribution within simple inorganic molecules by Sir William Henry Bragg and his son, William Lawrence Bragg. The idea of extension of this method to biological molecules met initially with considerable skepticism. For over two decades many respected scientists doubted whether it could be done. Yet, despite its bottlenecks (some of which are described below), the superiority of X-ray crystallography over all other approaches for shedding light on functional aspects at the molecular level became evident once the first structure was determined. The power of this method inspired continuous efforts and spectacular innovations, which vastly accelerated its incredible expansion. Consequently, over the last six decades biological crystallography has produced a constantly growing number of structures, some of which were considered formidable. This remarkable advance yielded numerous new insights into intricate functional aspects. Owing to space limitation this article focuses on selected studies performed recently and highlights some recent exciting developments.
Collapse
|
216
|
Kawaguchi M, Okabe T, Okudaira S, Hanaoka K, Fujikawa Y, Terai T, Komatsu T, Kojima H, Aoki J, Nagano T. Fluorescence probe for lysophospholipase C/NPP6 activity and a potent NPP6 inhibitor. J Am Chem Soc 2011; 133:12021-30. [PMID: 21721554 DOI: 10.1021/ja201028t] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Nucleotide pyrophosphatases/phosphodiesterases (NPPs) are ubiquitous membrane-associated or secreted ectoenzymes that have a role in regulating extracellular nucleotide and phospholipid metabolism. Among the members of the NPP family, NPP1 and -3 act on nucleotides such as ATP, while NPP2, -6, and -7 act on phospholipids such as lysophosphatidylcholine and sphingomyelin. NPP6, a recently characterized NPP family member, is a choline-specific glycerophosphodiester phosphodiesterase, but its functions remain to be analyzed, partly due to the lack of highly sensitive activity assay systems and practical inhibitors. Here we report synthesis of novel NPP6 fluorescence probes, TG-mPC and its analogues TG-mPC(3)C, TG-mPC(5)C, TG-mPENE, TG-mPEA, TG-mPhos, TG-mPA, TG-mPMe, and TG-mPPr. Among the seven NPPs, only NPP6 hydrolyzed TG-mPC, TG-mPC(3)C, and TG-mPENE. TG-mPC was hydrolyzed in the cell lysate from NPP6-transfected cells, but not control cells, showing that it is suitable for use in cell-based NPP6 assays. We also examined the usefulness of TG-mPC as a fluorescence imaging probe. We further applied TG-mPC to carry out high-throughput NPP6 inhibitor screening and found several NPP6-selective inhibitors in a library of about 80,000 compounds. Through structure-activity relationship (SAR) analysis, we identified a potent and selective NPP6 inhibitor with an IC(50) value of 0.21 μM. Our NPP6-selective fluorescence probe, TG-mPC, and the inhibitor are expected to be useful to elucidate the biological function of NPP6.
Collapse
Affiliation(s)
- Mitsuyasu Kawaguchi
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Tokyo 113-0033, Japan
| | | | | | | | | | | | | | | | | | | |
Collapse
|
217
|
Albers HMHG, Hendrickx LJD, van Tol RJP, Hausmann J, Perrakis A, Ovaa H. Structure-based design of novel boronic acid-based inhibitors of autotaxin. J Med Chem 2011; 54:4619-26. [PMID: 21615078 PMCID: PMC3131786 DOI: 10.1021/jm200310q] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Autotaxin (ATX) is a secreted phosphodiesterase that hydrolyzes the abundant phospholipid lysophosphatidylcholine (LPC) to produce lysophosphatidic acid (LPA). The ATX-LPA signaling axis has been implicated in inflammation, fibrosis, and tumor progression, rendering ATX an attractive drug target. We recently described a boronic acid-based inhibitor of ATX, named HA155 (1). Here, we report the design of new inhibitors based on the crystal structure of ATX in complex with inhibitor 1. Furthermore, we describe the syntheses and activities of these new inhibitors, whose potencies can be explained by structural data. To understand the difference in activity between two different isomers with nanomolar potencies, we performed molecular docking experiments. Intriguingly, molecular docking suggested a remarkable binding pose for one of the isomers, which differs from the original binding pose of inhibitor 1 for ATX, opening further options for inhibitor design.
Collapse
Affiliation(s)
- Harald M H G Albers
- Division of Cell Biology, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | | | | | | | | | | |
Collapse
|
218
|
Tabchy A, Tigyi G, Mills GB. Location, location, location: a crystal-clear view of autotaxin saturating LPA receptors. Nat Struct Mol Biol 2011; 18:117-8. [PMID: 21289650 PMCID: PMC3584164 DOI: 10.1038/nsmb0211-117] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The interaction of autotaxin with its substrates leads to the production of lysophosphatidic acids (LPA), bioactive lipids with an emerging prominent role in inflammation and cancer. Two papers in this issue tell the previously unknown story of autotaxin, from substrate discrimination to highly efficient local delivery of LPA to target receptors.
Collapse
Affiliation(s)
- Adel Tabchy
- Department of Systems Biology, Kleberg Center for Molecular Markers, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Gabor Tigyi
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee, USA
| | - Gordon B Mills
- Department of Systems Biology, Kleberg Center for Molecular Markers, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| |
Collapse
|