Dataset Information

Molecular basis of antiangiogenic thrombospondin-1 type 1 repeat domain interactions with CD36.

ABSTRACT: Antiangiogenic activity of thrombospondin-1 and related proteins is mediated by interactions between thrombospondin type 1 repeat (TSR) domains and the CD36, LIMP-2, Emp sequence homology (CLESH) domain of the endothelial cell receptor CD36. We sought to characterize key molecular determinants of the interaction between thrombospondin-1 TSR domains and the CD36 CLESH domain.Recombinant thrombospondin-1 TSR2 and TSR(2,3) constructs inhibited microvascular endothelial cell migration, microvascular endothelial cell tube formation, and vessel sprouting in aortic ring assays. Interaction with CD36 CLESH decoy peptides negated these effects. Mutational analyses identified a cluster of residues that confer positive charge to the TSR2 surface and mediate interaction with CD36 CLESH. Antiangiogenic activity was significantly reduced by charge-neutralizing mutations of the Arg-Trp ladder in TSR2, but not TSR3. Additionally, I438 and K464 of TSR2 were shown to be required for CD36 CLESH binding to TSR2. A complementary acidic cluster within CD36 CLESH is also required for antiangiogenic activity.Thrombospondin-1 interacts with CD36 CLESH through electrostatic interactions mediated by a positively charged TSR2 surface and multiple negatively charged CD36 CLESH residues. Two key residues serve as specificity determinants that identify other TSR domains that interact with CD36 CLESH.

SUBMITTER: Klenotic PA

PROVIDER: S-EPMC3737738 | biostudies-literature | 2013 Jul

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Molecular basis of antiangiogenic thrombospondin-1 type 1 repeat domain interactions with CD36.

Klenotic Philip A PA Page Richard C RC Li Wei W Amick Joseph J Misra Saurav S Silverstein Roy L RL

Arteriosclerosis, thrombosis, and vascular biology 20130502 7

<h4>Objective</h4>Antiangiogenic activity of thrombospondin-1 and related proteins is mediated by interactions between thrombospondin type 1 repeat (TSR) domains and the CD36, LIMP-2, Emp sequence homology (CLESH) domain of the endothelial cell receptor CD36. We sought to characterize key molecular determinants of the interaction between thrombospondin-1 TSR domains and the CD36 CLESH domain.<h4>Approach and results</h4>Recombinant thrombospondin-1 TSR2 and TSR(2,3) constructs inhibited microvas ...[more]

PMID: 23640500

Similar Datasets

Project description:BackgroundIdiopathic membranous nephropathy is an autoimmune disease. In approximately 70% of patients, it is associated with autoantibodies against the phospholipase A2 receptor 1 (PLA2R1). Antigenic targets in the remaining patients are unknown.MethodsUsing Western blotting, we screened serum samples from patients with idiopathic membranous nephropathy, patients with other glomerular diseases, and healthy controls for antibodies against human native glomerular proteins. We partially purified a putative new antigen, identified this protein by means of mass spectrometry of digested peptides, and validated the results by analysis of recombinant protein expression, immunoprecipitation, and immunohistochemical analysis.ResultsSerum samples from 6 of 44 patients in a European cohort and 9 of 110 patients in a Boston cohort with anti-PLA2R1-negative idiopathic membranous nephropathy recognized a glomerular protein that was 250 kD in size. None of the serum samples from the 74 patients with idiopathic membranous nephropathy who were seropositive for anti-PLA2R1 antibodies, from the 76 patients with other glomerular diseases, and from the 44 healthy controls reacted against this antigen. Although this newly identified antigen is clearly different from PLA2R1, it shares some biochemical features, such as N-glycosylation, membranous location, and reactivity with serum only under nonreducing conditions. Mass spectrometry identified this antigen as thrombospondin type-1 domain-containing 7A (THSD7A). All reactive serum samples recognized recombinant THSD7A and immunoprecipitated THSD7A from glomerular lysates. Moreover, immunohistochemical analyses of biopsy samples from patients revealed localization of THSD7A to podocytes, and IgG eluted from one of these samples was specific for THSD7A.ConclusionsIn our cohort, 15 of 154 patients with idiopathic membranous nephropathy had circulating autoantibodies to THSD7A but not to PLA2R1, a finding that suggests a distinct subgroup of patients with this condition. (Funded by the French National Center for Scientific Research and others.).

Project description:The aim of this study is to identify Arabidopsis genes whose expression is altered by aphid feeding. An understanding of the plant aphid interaction at the level of the plant transcriptome will 1) consolidate current areas of investigation focused on the phloem composition (the aphid diet), 2) open up areas of plant aphid interactions for ourselves and other workers, 3) Contribute to understanding the use of new molecular technologies in an environmental context and 4) contribute to existing and development of novel control strategies.Our Arabidopsis/Myzus persicae system provides a valuable model for the study because of: a) the advantages of using Arabidopsis, b) The ability to use clonal insects, c) phloem feeding aphids facilitate focus on a specific cell type, d) aphid stylectomy allows collection of pure phloem sap to monitor phloem phenotype of the plant and the insect diet, e) we have techniques to monitor the reproductive performance and feeding behaviour aphids.Our strategy has been to test the function of selected genes, particularly those regulating phloem composition (the feeding site of the aphid) based on current phloem models of phloem function. Gene choice is limited the simplicity of current models of phloem aphid interaction.We propose a simple two treatment (aphid infested vs control plants) experiment that will identify novel target genes for future analysis. Arabidopsis plants (variety Columbia) will be grown in 16/8 light/dark in temperature controlled growth rooms. At growth stage 3.90, when rosette growth is complete, 10 clonal adult Myzus persicae will be caged in clip cages on the two largest leaves on each plant. Control plants will be treated identically except that the cages will be empty. Leaves will be harvested 8 h after infestation. This time point is selected as we know that 90% of aphids are plugged into the sieve element within 2h and that a 6h lag phase has period has previously been used when examining gene expression affected by wounding. In subsequent experiments we will examine time courses of expression of relevant genes using other approaches. Pooling two leaves from each of ten plants will generate the RNA sample, ensuring that expression signals are representative of the population of plants. Experimenter name: Jeremy Pritchard Experimenter phone: 0121 414 5570 Experimenter fax: 0121 414 5925 Experimenter institute: University of Birmingham Experimenter address: School of Biosciences Experimenter address: University of Birmingham, Edgbaston, Birmingham, West Midlands Experimenter zip/postal_code: B30 2EN Experimenter country: UK Keywords: pathogenicity_design

Dataset Information

Molecular basis of antiangiogenic thrombospondin-1 type 1 repeat domain interactions with CD36.

Publications

Molecular basis of antiangiogenic thrombospondin-1 type 1 repeat domain interactions with CD36.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets