37
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: not found

      Structural basis for substrate discrimination and integrin binding by autotaxin

      research-article

      Read this article at

      ScienceOpenPublisherPMC
      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Autotaxin (ATX) or ecto-nucleotide pyrophosphatase/phosphodiesterase-2 (ENPP2) is a secreted lysophospholipase D that generates the lipid mediator lysophosphatidic acid (LPA), a mitogen and chemo-attractant for many cell types. ATX-LPA signaling has roles in various pathologies including tumour progression and inflammation. However, the molecular basis of substrate recognition and catalysis, and the mechanism of interaction with target cells, has been elusive. Here we present the crystal structure of ATX, alone and in complex with a small-molecule inhibitor. We identify a hydrophobic lipid-binding pocket and map key residues required for catalysis and selection between nucleotide and phospholipid substrates. We show that ATX interacts with cell-surface integrins via its N-terminal somatomedin-B-like domains, using an atypical mechanism. Our results define determinants of substrate discrimination by the ENPP family, suggest how ATX promotes localized LPA signaling, and enable new approaches to target ATX with small-molecule therapeutics.

          Related collections

          Most cited references38

          • Record: found
          • Abstract: found
          • Article: not found

          Refinement of severely incomplete structures with maximum likelihood in BUSTER-TNT.

          BUSTER-TNT is a maximum-likelihood macromolecular refinement package. BUSTER assembles the structural model, scales observed and calculated structure-factor amplitudes and computes the model likelihood, whilst TNT handles the stereochemistry and NCS restraints/constraints and shifts the atomic coordinates, B factors and occupancies. In real space, in addition to the traditional atomic and bulk-solvent models, BUSTER models the parts of the structure for which an atomic model is not yet available ('missing structure') as low-resolution probability distributions for the random positions of the missing atoms. In reciprocal space, the BUSTER structure-factor distribution in the complex plane is a two-dimensional Gaussian centred around the structure factor calculated from the atomic, bulk-solvent and missing-structure models. The errors associated with these three structural components are added to compute the overall spread of the Gaussian. When the atomic model is very incomplete, modelling of the missing structure and the consistency of the BUSTER statistical model help structure building and completion because (i) the accuracy of the overall scale factors is increased, (ii) the bias affecting atomic model refinement is reduced by accounting for some of the scattering from the missing structure, (iii) the addition of a spatial definition to the source of incompleteness improves on traditional Luzzati and sigmaA-based error models and (iv) the program can perform selective density modification in the regions of unbuilt structure alone.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            The lysophosphatidic acid receptor LPA1 links pulmonary fibrosis to lung injury by mediating fibroblast recruitment and vascular leak.

            Aberrant wound-healing responses to injury have been implicated in the development of pulmonary fibrosis, but the mediators directing these pathologic responses have yet to be fully identified. We show that lysophosphatidic acid levels increase in bronchoalveolar lavage fluid following lung injury in the bleomycin model of pulmonary fibrosis, and that mice lacking one of its receptors, LPA1, are markedly protected from fibrosis and mortality in this model. The absence of LPA1 led to reduced fibroblast recruitment and vascular leak, two responses that may be excessive when injury leads to fibrosis rather than to repair, whereas leukocyte recruitment was preserved during the first week after injury. In persons with idiopathic pulmonary fibrosis, lysophosphatidic acid levels in bronchoalveolar lavage fluid were also increased, and inhibition of LPA1 markedly reduced fibroblast responses to the chemotactic activity of this fluid. LPA1 therefore represents a new therapeutic target for diseases in which aberrant responses to injury contribute to fibrosis, such as idiopathic pulmonary fibrosis.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Autotaxin has lysophospholipase D activity leading to tumor cell growth and motility by lysophosphatidic acid production

              Autotaxin (ATX) is a tumor cell motility–stimulating factor, originally isolated from melanoma cell supernatants. ATX had been proposed to mediate its effects through 5′-nucleotide pyrophosphatase and phosphodiesterase activities. However, the ATX substrate mediating the increase in cellular motility remains to be identified. Here, we demonstrated that lysophospholipase D (lysoPLD) purified from fetal bovine serum, which catalyzes the production of the bioactive phospholipid mediator, lysophosphatidic acid (LPA), from lysophosphatidylcholine (LPC), is identical to ATX. The Km value of ATX for LPC was 25-fold lower than that for the synthetic nucleoside substrate, p-nitrophenyl-tri-monophosphate. LPA mediates multiple biological functions including cytoskeletal reorganization, chemotaxis, and cell growth through activation of specific G protein–coupled receptors. Recombinant ATX, particularly in the presence of LPC, dramatically increased chemotaxis and proliferation of multiple different cell lines. Moreover, we demonstrate that several cancer cell lines release significant amounts of LPC, a substrate for ATX, into the culture medium. The demonstration that ATX and lysoPLD are identical suggests that autocrine or paracrine production of LPA contributes to tumor cell motility, survival, and proliferation. It also provides potential novel targets for therapy of pathophysiological states including cancer.
                Bookmark

                Author and article information

                Journal
                101186374
                31761
                Nat Struct Mol Biol
                Nature structural & molecular biology
                1545-9993
                1545-9985
                12 November 2010
                16 January 2011
                February 2011
                1 August 2011
                : 18
                : 2
                : 198-204
                Affiliations
                [1 ]Division of Biochemistry, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
                [2 ]Pfizer Global Research and Development, Chesterfield, MO 63017, USA
                [3 ]Division of Cardiovascular Medicine, University of Kentucky, Lexington, KY 40536, USA
                [4 ]Division of Cell Biology, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
                [5 ]Laboratory of Biosignaling & Therapeutics, Department of Molecular Cell Biology, University of Leuven, B-3000 Leuven, Belgium
                [6 ]Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
                Author notes
                [7]

                These authors contributed equally to this work

                J.H. purified, crystallized and collected diffraction data for native crystal forms; established co-crystals, collected diffraction data and participated in structure determination of the HA155 complex; and cloned, expressed and assayed activity of catalytic and binding site mutants; S.K. directly supervised Pfizer scientists, collected and processed diffraction data, determined the first structure, built and refined crystal structures; E.C. established cell lines, protein expression and purification, crystallization protocols for the first native crystal form, and collected diffraction data; J.E.D. identified and produced the second, high resolution, native crystal form and collected diffraction data; T.W. and Z.F. generated all reagents for ATX platelet binding experiments and performed the relevant assays; L.v.M participated in protein expression and with H.M.H.G.A. and A.H help to establish ATX assays; H.M.H.G.A made the HA155 inhibitor; L.v.Z contributed the PAI-1 experiment; S.J. generated the rATX mutant used for crystallization, M.A. performed the EF-hand-like mutagenesis experiments and assays; L.E.P. expressed protein; T.E.B. coordinated the Pfizer scientists; K.H assisted with crystal growth, manipulation and data collection; M.K. helped establish the stable cell line producing rATX; CvdK, S.S.S and A.J.M. designed and supervised platelet binding experiments; H.O. supervised inhibitor design at the NKI site; M.B. supervised EF-hand experiments and participated in project coordination; W.H.M. and A.P. initiated and coordinated the project and supervised experiments at the NKI; A.P. also determined and refined crystal structures, prepared all display items, and wrote the paper with input from W.H.M., S.K., M.B. and A.J.M.

                Correspondence and requests for materials should be addressed to A.J..M., W.H.M. and A.P. ( amorr6@ 123456email.uky.edu , w.moolenaar@ 123456nki.nl and a.perrakis@ 123456nki.nl ).
                Article
                nihpa251225
                10.1038/nsmb.1980
                3064516
                21240271
                18a00078-d5ea-4b42-9425-f5c8bc04f3cc

                Users may view, print, copy, download and text and data- mine the content in such documents, for the purposes of academic research, subject always to the full Conditions of use: http://www.nature.com/authors/editorial_policies/license.html#terms

                History
                Funding
                Funded by: National Heart, Lung, and Blood Institute : NHLBI
                Funded by: National Institute of General Medical Sciences : NIGMS
                Funded by: National Center for Research Resources : NCRR
                Award ID: R01 HL078663-06 ||HL
                Funded by: National Heart, Lung, and Blood Institute : NHLBI
                Funded by: National Institute of General Medical Sciences : NIGMS
                Funded by: National Center for Research Resources : NCRR
                Award ID: R01 GM050388-18 ||GM
                Funded by: National Heart, Lung, and Blood Institute : NHLBI
                Funded by: National Institute of General Medical Sciences : NIGMS
                Funded by: National Center for Research Resources : NCRR
                Award ID: P20 RR021954-03 ||RR
                Categories
                Article

                Molecular biology
                Molecular biology

                Comments

                Comment on this article