MABSol® Biotinylated Human SOST / Sclerostin (SOT-H8245) is expressed from human HEK293 cells. It contains AA Gln 24 - Tyr 213 (Accession # AAI01087.1). It is the biotinylated form of Human SOST / Sclerostin Protein (Cat # HST-H5245).
This protein carries a polyhistidine tag at the N-terminus. The protein has a calculated MW of 22.5 kDa. The protein migrates as 25-36 kDa on a SDS-PAGE gel under reducing (R) condition due to different glycosylation.
The primary amines in the side chains of lysine residues and the N-terminus of the protein are conjugated with biotins using standard chemical labeling method. A standard biotin reagent (13.5 angstroms) is used in this product.
The biotin to protein ratio is 4-6 as determined by the HABA assay.
Less than 1.0 EU per μg by the LAL method.
>95% as determined by reduced SDS-PAGE.
Lyophilized from 0.22 μm filtered solution in PBS, pH7.4. Normally trehalose is added as protectant before lyophilization.
Contact us for customized product form or formulation.
Please see Certificate of Analysis for specific instructions.
For best performance, we strongly recommend you to follow the reconstitution protocol provided in the CoA.
For long term storage, the product should be stored at lyophilized state at -20°C or lower.
Please avoid repeated freeze-thaw cycles.
No activity loss is observed after storage at:
4-8°C for 12 months in lyophilized state;
-70°C for 3 months under sterile conditions after reconstitution.
Biotinylated Human SOST on SDS-PAGE under reducing (R) condition. The gel was stained overnight with Coomassie Blue. The purity of the protein is greater than 95%.
Sclerostin (SOST) also known as Sclerosteosis, VBCH, is a secreted glycoprotein with a signal peptide for secretion and a C-terminal cysteine knot-like (CTCK) domain and belongs to the Cerberus/DAN family of bone morphogenetic protein (BMP) antagonists. Sclerostin is produced by the osteocyte and has anti-anabolic effects on bone formation. More recently Sclerostin has been identified as binding to LRP5/6 receptors and inhibiting the Wnt signalling pathway. Wnt pathway inhibition under these circumstances is antagonistic to bone formation (meaning Sclerostin antagonizes bone formation). It has been shown that SOST binds BMP-5, -6, and -7 with high affinity and BMP-2 and -4 with low affinity. Sclerostin production by osteocytes is inhibited by parathyroid hormone, mechanical loading and cytokines including oncostatin M, cardiotrophin-1 and leukemia inhibitory factor. Sclerostin production is increased by calcitonin. Thus, osteoblast activity is self regulated by a negative feedback system. Mutations of Sclerostin is associated with the syndrome Sclerosteosis, and reduced sclerostin expression results in a milder form of the disorder called van Buchem disease.