The International Journal of Biochemistry & Cell Biology
ReviewThe N-terminus of thrombospondin: the domain stands apart
Introduction
In 1978, thrombospondin 1 (TSP1) was first recognized to be a heparin-binding protein by Lawler, Slayter, and Coligan (1978) and in 1984, the localization of this heparin-binding region to the amino-terminus of TSP1 was reported (Dixit, Grant, Santoro, & Frazier, 1984). This amino-terminal domain can be generated by multiple proteases (Dixit et al., 1984; Lawler & Slayter, 1981). The generation of monoclonal antibodies (A2.5, MAII) by the Frazier and Lawler labs (Galvin et al., 1985; Lawler, Derick, Connolly, Chen, & Chao, 1985) was important for modeling of TSP’s domains and for providing initial insights into the function of TSP1 and the N-terminal heparin binding domain (HBD) (Dixit et al., 1985, Galvin et al., 1985). The first functions blocked by antibodies to the HBD were hemagglutination of fixed erythrocytes and agglutination of fixed, activated platelets (Dixit et al., 1985). In the nearly 20 years since these reports, the structure and function of the HBD has been investigated by numerous investigators. One unexpected finding is the diverse array of molecular interactions identified for this domain (Fig. 1). Receptors and molecular binding partners for the HBD as well as in vitro functions of this molecule will be reviewed here.
Section snippets
Structure of the N domain
The N-terminus of TSP1 and TSP2 has sequence similarity to the laminin G and pentraxin superfamily of globular proteins, characterized by its globular structure with patterns of alternating hydrophobicity characteristic of anti-parallel β-strands, suggesting that the N-terminus might have a similar conformation although this has not been confirmed by structural studies (Beckmann, Hanke, Bork, & Reich, 1998). The N-terminus is the major heparin-binding site of TSP1 and TSP2 and there are at
Sulfatides
The basic amino acids of the HBD are involved in charge-dependent interactions with sulfatides. Recombinant HBD (aa1–174) binds to sulfatides, however synthetic peptides from residues 23–32 and 77–84 which inhibit TSP1 binding to heparin, had no effect on sulfatide binding (Guo et al., 1992), suggesting that binding to sulfatide likely requires cooperation of several basic sequences and is dependent on the three-dimensional structure of TSP1. Binding of TSP1 to sulfatides can be inhibited by
Functions of the HBD
The HBD of TSPs has multiple interactions with a diverse array of macromolecules and cellular receptors. The signals elicited through cellular interactions with the HBD are complicated and depend on its solubility, valency, and the receptors it engages. The HBD has distinct functions as both a soluble and an immobilized molecule. In soluble form, the HBD is de-adhesive, yet when it is immobilized, the HBD can support cellular adhesion to a variable extent (Ferrari do Outeiro-Bernstein et al.,
The physiologic relevance of the HBD of TSP
TSPs are complex multifunctional molecules. The N-terminal HBD domain has functions distinct from other domains or even the whole TSP molecule. One of the factors confounding our ability to understand TSPs’ functions is the diversity of receptors for this molecule and apparently paradoxical effects of its isolated domains. Despite nearly 20 years of investigation, the physiologic function of TSPs and its HBDs remain unclear. Patterns of receptor expression and expression levels can clearly
Acknowledgements
The original work reported in this review was supported by NIH HL44575. CAE is supported by NIH Training grant T32 AR47512-02 in Comprehensive Training Grant in Bone Biology and Disease.
References (71)
- et al.
Thrombospondins 1 and 2 function as inhibitors of angiogenesis
Matrix Biology
(2003) - et al.
Cellular attachment to thrombospondin. Cooperative interactions between receptor systems
Journal of Biological Chemistry
(1991) - et al.
Merging extracellular domains: Fold prediction for laminin G-like and amino-terminal thrombospondin-like modules based on homology to pentraxins
Journal of Molecular Biology
(1998) - et al.
Proteolysis of subendothelial adhesive glycoproteins (fibronectin, thrombospondin, and von Willebrand factor) by plasmin, leukocyte cathepsin G, and elastase
Thrombosis Research
(2000) - et al.
Recognition of the N-terminal modules of thrombospondin-1 and thrombospondin-2 by alpha6beta1 integrin
Journal of Biological Chemistry
(2003) - et al.
Pro-adhesive and chemotactic activities of thrombospondin-1 for breast carcinoma cells are mediated by alpha3beta1 integrin and regulated by insulin-like growth factor-1 and CD98
Journal of Biological Chemistry
(1999) - et al.
The cell biology of thrombospondin-1
Matrix Biology
(2000) - et al.
Metabolism of thrombospondin. 2. Binding and degradation by 3t3 cells and glycosaminoglycan-variant Chinese hamster ovary cells
Journal of Biological Chemistry
(1996) - et al.
Identification of integrin alpha 3 beta 1 as a neuronal thrombospondin receptor mediating neurite outgrowth
Neuron
(1995) - et al.
Isolation and characterization of a heparin-binding domain from the amino terminus of platelet thrombospondin
Journal of Biological Chemistry
(1984)
Calreticulin is released from activated neutrophils and binds to C1q and mannan-binding protein
Clinical and Immunological Immunopathology
Interaction of thrombospondin-1 and heparan sulfate from endothelial cells. Structural requirements of heparan sulfate
Journal of Biological Chemistry
A recombinant NH(2)-terminal heparin-binding domain of the adhesive glycoprotein, thrombospondin-1, promotes endothelial tube formation and cell survival: A possible role for syndecan-4 proteoglycan
Matrix Biology
Thrombospondin mediates focal adhesion disassembly through interactions with cell surface calreticulin
Journal of Biological Chemistry
The anti-adhesive activity of thrombospondin is mediated by the N-terminal domain of cell surface calreticulin
Journal of Biological Chemistry
Identification of an alpha(3)beta(1) integrin recognition sequence in thrombospondin-1
Journal of Biological Chemistry
The structure of human platelet thrombospondin
Journal of Biological Chemistry
The release of heparin binding peptides from platelet thrombospondin by proteolytic action of thrombin
Thrombosis Research
Isolation and characterization of a high molecular weight glycoprotein from human blood platelets
Journal of Biological Chemistry
Cellular internalization and degradation of thrombospondin-1 is mediated by the amino-terminal heparin binding domain (HBD). High affinity interaction of dimeric HBD with the low density lipoprotein receptor-related protein
Journal of Biological Chemistry
Low density lipoprotein receptor-related protein/alpha 2-macroglobulin receptor mediates the cellular internalization and degradation of thrombospondin. A process facilitated by cell-surface proteoglycans
Journal of Biological Chemistry
Heparin-binding peptides from thrombospondins 1 and 2 contain focal adhesion-labilizing activity
Journal of Biological Chemistry
Altered metabolism of thrombospondin by Chinese hamster ovary cells defective in glycosaminoglycan synthesis
Journal of Biological Chemistry
Calreticulin is transcriptionally upregulated by heat shock
Molecular Immunology
Thrombospondin stimulates focal adhesion disassembly through Gi- and phosphoinositide 3-kinase-dependent ERK activation
Journal of Biological Chemistry
Retinoic acid alters the mechanism of attachment of malignant astrocytoma and neuroblastoma cells to thrombospondin-1
Experimental Cell Research
Proteolysis of thrombospondin during cathepsin-G-induced platelet aggregation: Functional role of the 165-kDa carboxy-terminal fragment
FEBS Letters
The platelet glycoprotein thrombospondin binds specifically to sulfated glycolipids
Journal of Biological Chemistry
Expresson of vascular endothelial growth factor, its receptors (FLT-1, KDR) and TSP1 related to microvessel density and patient outcome in vertical growth phase melanomas
American Journal of Pathology
Heparan sulfate-mediated binding of epithelial cell surface proteoglycan to thrombospondin
Journal of Biological Chemistry
Extracellular matrix metalloproteinase 2 levels are regulated by the low density lipoprotein-related scavenger receptor and thrombospondin 2
Journal of Biological Chemistry
Diverse mechanisms for cell attachment to platelet thrombospondin
Journal of Cell Science
Cell-type specific adhesive interactions of skeletal myoblasts with thrombospondin-1
Molecular Biology of the Cell
A role for syndecan-1 in coupling fascin spike formation by thrombospondin-1
Journal of Cell Biology
Thrombospondin-1 and -2 messenger RNA expression in normal, benign, and neoplastic human breast tissues: Correlation with prognostic factors, tumor angiogenesis, and fibroblastic desmoplasia
Cancer Research
Cited by (67)
Molecular insights into the effect of an apoptotic raft-like bilayer on the conformation and dynamics of calreticulin
2020, Biochimica et Biophysica Acta - BiomembranesCitation Excerpt :Structurally, CRT consists of three domains [10]: N-domain, a globular structure containing eight anti-parallel β strands; P-domain, a proline-rich structure (like a tail); and C-domain, a highly acidic domain terminates with KDEL sequence. TSP1 is a large (420 kDa) homotrimeric glycoprotein, and each monomer of TSP1 is composed of N- and C-terminal globular domains [11,12]. TSP1 uses its N-terminal domain to interact with CRT, and the CRT-binding site of TSP1 is localized to amino acids 17–35 (ELTGAARKGSGRRLVKGPD) [13].
Serotype 3 pneumococci sequester platelet-derived human thrombospondin-1 via the adhesin and immune evasion protein Hic
2017, Journal of Biological ChemistryEngineered tissue inhibitor of metalloproteinases-3 variants resistant to endocytosis have prolonged chondroprotective activity
2016, Journal of Biological ChemistryCitation Excerpt :Extracellular levels of other LRP1 ligands may be similarly regulated by the equilibrium between matrix binding and LRP1-mediated uptake that we have observed for TIMP-3. For example, heparin inhibits LRP1 binding of factor IXa (35), apolipoprotein A-V (36), C4b-binding protein (37), and PAI-1 (38, 39), and several other LRP1 ligands (e.g. ADAMTS-4, ADAMTS-5, MMP-13, TGFβ, CTGF, midkine, thrombospondin) are known to bind to heparin or heparan sulfate (40–46). The bioavailability of these proteins is thus likely to be modulated by factors governing their retention on heparan sulfate proteoglycans, such as the pattern and degree of sulfation on heparan sulfate.
Degradome products of the matricellular protein CCN1 as modulators of pathological angiogenesis in the retina
2013, Journal of Biological ChemistryThrombospondin-1 is a CD47-dependent endogenous inhibitor of hydrogen sulfide signaling in T cell activation
2013, Matrix BiologyCitation Excerpt :TSP1 mediates these activities by binding to other extracellular matrix components and growth factors, mediating activation of latent TGF-β1 (Schultz-Cherry and Murphy-Ullrich, 1993; Sweetwyne and Murphy-Ullrich, 2012), and binding to at least 12 different cell surface receptors(Murphy-Ullrich and Iozzo, 2012). These receptors include five integrins (Lawler et al., 1988; Chandrasekaran et al., 2000; Calzada et al., 2003, 2004a, 2004b; Staniszewska et al., 2007), CD36 (Dawson et al., 1997), CD47 (Gao et al., 1996), CD148 (Takahashi et al., 2012), calreticulin/low density lipoprotein receptor-related protein-1 (LRP1) (Elzie and Murphy-Ullrich, 2004), proteoglycans (Feitsma et al., 2000), and sulfatides (Guo et al., 1992). Among these, TSP1 has the highest affinity for CD47, and this receptor is both necessary and sufficient for TSP1 to inhibit NO-cGMP signaling (Isenberg et al., 2006).