Detection of Human Thrombospondin‑4 by Western Blot.
Western blot shows lysates of human heart tissue. PVDF membrane was probed with 1 µg/mL of Mouse Anti-Human Thrombospondin‑4 Monoclonal Antibody (Catalog # MAB2390) followed by HRP-conjugated Anti-Mouse IgG Secondary Antibody (Catalog # HAF007). A specific band was detected for Thrombospondin‑4 at approximately 130kDa (as indicated). This experiment was conducted under reducing conditions and using Immunoblot Buffer Group 1.
Preparation and Storage
Reconstitute at 0.5 mg/mL in sterile PBS.
Reconstitution Buffer Available
The product is shipped at ambient temperature. Upon receipt, store it immediately at the temperature recommended below. *Small pack size (SP) is shipped with polar packs. Upon receipt, store it immediately at -20 to -70 °C
Stability & Storage
Use a manual defrost freezer and avoid repeated freeze-thaw cycles.
12 months from date of receipt, -20 to -70 °C as supplied.
1 month, 2 to 8 °C under sterile conditions after reconstitution.
6 months, -20 to -70 °C under sterile conditions after reconstitution.
Thrombospondin-4 (TSP-4) is a 140 kDa calcium-binding protein that interacts with other extracellular matrix molecules and modulates the activity of various cell types. TSP‑1 and -2 constitute subgroup A and form disulfide-linked homotrimers, whereas TSP-3, -4, and -5/COMP constitute subgroup B and form pentamers (1, 2). The human TSP-4 cDNA encodes a 961 amino acid (aa) precursor that includes a 26 aa signal sequence followed by an N-terminal heparin-binding domain, a coiled-coil motif, four EGF-like repeats, seven TSP type-3 repeats (one with an RGD motif), and a TSP C-terminal domain (3). Human TSP-4 shares 93% aa sequence identity with mouse and rat TSP-4. Within the TSP type-3 repeats and the TSP C-terminal domain, human TSP-4 shares 79% aa sequence identity with TSP-3 and COMP, and 58% aa sequence identity with TSP-1 and -2. The coiled-coil motif mediates pentamer formation with COMP, either homotypically or heterotypically (3-6). TSP-4 binds a variety of matrix proteins including collagens I, II, III, V, laminin-1, fibronectin, and matrilin-2 (4). Interactions of TSP-4 with non-collagenous proteins are independent of divalent cations, while interactions with collagenous proteins are enhanced in the presence of zinc (4). TSP-4 is expressed in heart, skeletal muscle, vascular smooth muscle, and vascular endothelial cells (7-9). It accumulates at neuromuscular junctions and synapse-rich regions and is upregulated in muscle by experimental denervation (8). TSP-4 mediates the adhesion of motor and sensory neurons and promotes neurite outgrowth (8). A polymorphism of TSP-4 (A387P) is associated with early coronary artery disease (10-12). Unlike wild type TSP-4, the A387P variant does not support HUVEC attachment and spreading (9). Integrin alpha M/ beta 2 enables activated neutrophil adhesion to both the variant A387P and wild type TSP-4, although the A387P variant induces a greater release of proinflammatory molecules (13).
Adams, J.C. and J. Lawler (2004) Int. J. Biochem. Cell Biol. 36:961.
Stenina, O.I. et al. (2004) Int. J. Biochem. Cell Biol. 36:1013.
Lawler, J. et al. (1995) J. Biol. Chem. 270:2809.
Narouz-Ott, L. et al. (2000) J. Biol. Chem. 275:37110.
Hauser, N. et al. (1995) FEBS Lett. 368:307.
Sodersten, F. et al. (2006) Connect. Tissue Res. 47:85.
Lawler, J. et al. (1993) J. Cell Biochem. 120:1059.
Arber, S. and P. Caroni (1995) J. Cell Biol. 131:1083.
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