Technical Data
Osteonectin (SPARC, Secreted Protein, Acidic, Cysteine-rich, ON, OSN)
SPARC, an acronym for “secreted protein, acidic and rich in cysteine”, is also known as osteonectin or BM-40. It is the founding member of a family of secreted matricellular proteins with similar domain structure. The 303 amino acid , 43 kD protein contains a 17 aa signal sequence, an N-terminal acidic region that binds calcium, a follistatin domain containing Kazal-like sequences, and a C-terminal extracellular calcium (EC) binding domain with two EF-hand motifs . SPARC is produced by fibroblasts, capillary endothelial cells, platelets and macrophages, especially in areas of tissue morphogenesis and remodeling. SPARC shows context-specific effects, but generally inhibits adhesion, spreading and proliferation, and promotes collagen matrix formation. For endothelial cells, SPARC disrupts focal adhesions and binds and sequesters PDGF and VEGF. SPARC is abundantly expressed in bone, where it promotes osteoblast differentiation and inhibits adipogenesis.

Suitable for use in RIA, ELISA, Western Blot and Immunohistochemistry. Other applications have not been tested.

Recommended Dilutions:
ELISA: Calcium dependent
Western Blot: 5ug/ml; Calcium dependent
Immunohistochemistry: Calcium dependent
Optimal dilutions to be determined by the researcher.

Extinction Coefficient: ~14.0

Storage and Stability:
May be stored at 4°C for short-term only. Aliquot to avoid repeated freezing and thawing. Store at -20°C. Aliquots are stable for 12 months after receipt. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.
MabIgG18.H.12Highly Purified
100ug-20°CBlue IceHumanMouse
Human bone osteonectin
Purified by ammonium sulfate precipitation, ion exchange chromatography and gel filtration.
Supplied as a liquid in 50% glycerol.
Recognizes human bone osteonectin. MW:150kD. Species Crossreactivity: rat and bovine bone osteonectin. Recognizes human platelet osteonectin as well as mouse osteonectin.
Intended for research use only. Not for use in human, therapeutic, or diagnostic applications.
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