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PhosphoSitePlus® Resource

  • Additional protein information
  • Analytical tools


Source / Purification

Recombinant Human His6IGFBP3 (hHis6IGFBP3) Gly28-Lys291 (Accession #NP_17936) was expressed in human 293 cells at Cell Signaling Technology.

Product Description


>95% as determined by SDS-PAGE of 6 μg reduced (+) and nonreduced (-) recombinant hHisIGFBP3. All lots are greater than 95% pure.

Molecular Formula:

Recombinant N-terminally His6-tagged hIGFBP3 has a calculated MW of 30,7123 Da. DTT reduced and nonreduced protein migrate as 50 kDa polypeptides. Lower mobility and heterogeneity in SDS-PAGE are due to glycosylation. The expected amino terminus of recombinant hHis6IGFBP3 was verified by amino acid sequencing.


The bioactivity of hHis6IGFBP3 was determined by inhibition of IGF-I induced AKT phosphorylation in human dermal fibroblasts. The ED50 of each lot is between 2.5-9 ng/ml.


Less than 0.01 ng endotoxin/1 μg hHis6IGFBP3.

Product Usage Information


With carrier: Lyophilized from a 0.22 μm filtered solution of hHis6IGFBP3 in 20 mM Tris, pH 7.2 containing 20 μg BSA per 1 μg hHis6IGFBP3. Carrier free: Lyophilized from a 0.22 μm filtered solution of hHis6IGFBP3 in 20 mM Tris, pH 7.2.

Storage: Stable in lyophilized state at 4°C for 1 year after receipt. Sterile stock solutions reconstituted with carrier protein are stable at 4°C for 2 months and at -20°C for 6 months. Avoid repeated freeze-thaw cycles. Maintain sterility. Storage at -20°C should be in a manual defrost freezer.

IGFBP3 is a multifunctional protein that plays a key role in regulation of IGFI/II activity, cell proliferation, and death. One of six high-affinity IGF binding proteins, IGFBP3 is the major species in circulation and is bound in a complex with ALS to 99% of hepatic IGF-I (1). Proteolytic degradation of IGFBP3 increases the bioavailability and activity of the IGF I/II (1). However, some biological activities of IGFBP3 are independent of the IGF/IGF-IR axis. IGFBP3 potentiates EGF-induced breast cancer cell proliferation in vitro by enhancing ERK phosphorylation and sphingosine kinase-mediated EGFR trans-activation (2,3). Conversely, IGFBP3 has been shown to induce apoptosis and inhibit NF-κB activity (4).

1.  Jogie-Brahim, S. et al. (2009) Endocr Rev 30, 417-37.

2.  Martin, J.L. et al. (2003) J Biol Chem 278, 2969-76.

3.  Martin, J.L. et al. (2009) J Biol Chem 284, 25542-52.

4.  Han, J. et al. (2011) Cancer Lett 307, 200-10.

Entrez-Gene Id 3486
Swiss-Prot Acc. P17936

For Research Use Only. Not For Use In Diagnostic Procedures.
Cell Signaling Technology is a trademark of Cell Signaling Technology, Inc.
PathScan is a trademark of Cell Signaling Technology, Inc.

Human His6IGFBP3 (hHis6IGFBP3)