Recombinant Human Insulin-like Growth Factor-Binding Protein 3

Synonyms Growth-hormone-dependant Binding Protein, IBP-3, IGF-binding protein 3

Accession P17936

GeneID 3486

Source Escherichia coli.

Molecular Weight Approximately 28.8 kDa, a single non-glycosylated polypeptide chain containing 264 amino acids.

Quantity 5µg/25µg/1mg

AA Sequence GASSGGLGPV VRCEPCDARA LAQCAPPPAV CAELVREPGC GCCLTCALSE GQPCGIYTER CGSGLRCQPS PDEARPLQAL LDGRGLCVNA SAVSRLRAYL LPAPPAPGNA SESEEDRSAG EVESPSVSST HRVSDPKFHP LHSKIIIIKK GHAKDSQRYK VDYESQSTDT QNFSSESKRE TEYGPCRREM EDTLNHLKFL NVLSPRGVHI PNCDKKGFYK KKQCRPSKGR KRGFCWCVDK YGQPLPGYTT KGKEDVHCYS MQSK

Purity > 98 % by SDS-PAGE and HPLC analyses.

Biological Activity Fully biologically active when compared to standard. The ED50 as determined by inhibiting IGF-II induced proliferation of serum free human MCF-7 cells is less than 200 ng/ml, corresponding to a specific activity of > 5.0 × 103 IU/mg in the presence of 15 ng/ml of rHuIGF-II.

Physical Appearance Sterile Filtered White lyophilized (freeze-dried) powder.

Formulation Lyophilized from a 0.2 μm filtered concentrated solution in PBS, pH 7.4.

Endotoxin Less than 1 EU/μg of rHuIGF-BP3 as determined by LAL method.

Reconstitution We recommend that this vial be briefly centrifuged prior to opening to bring the contents to the bottom. Reconstitute in sterile distilled water or aqueous buffer containing 0.1 % BSA to a concentration of 0.1-1.0 mg/mL. Stock solutions should be apportioned into working aliquots and stored at ≤ -20 °C. Further dilutions should be made in appropriate buffered solutions.

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.

- 3 months, -20 to -70 °C under sterile conditions after reconstitution.

Usage This material is offered by Shanghai PrimeGene Bio-Tech for research, laboratory or further evaluation purposes. NOT FOR HUMAN USE.

SDS-PAGE

Reference 1. Grellier P, Sabbah M, Fouqueray B, et al. 1996. Kidney Int, 49: 1071-8.

2. Yilmaz MD, Hosal AS, Oguz H, et al. 2002. Laryngoscope, 112: 922-5.

3. Deming SL, Ren Z, Wen W, et al. 2007. Breast Cancer Res Treat, 104: 309-19.

4. Satterfield MC, Hayashi K, Song G, et al. 2008. Biol Reprod, 79: 1226-36.

5. Key TJ, Appleby PN, Reeves GK, et al. 2010. Lancet Oncol, 11: 530-42.

Background Insulin-like Growth Factor-Binding Protein 3 (IGF-BP3) belongs to the IGFBP family, which are all cysteinerich proteins with conserved cysteine and have an IGFBP domain and a thyroglobulin type-I domain. Mature human IGF-BP3 contains 264 a.a. with three potential N-linked and two potential O-linked glycosylation sites. It is expressed by most tissues and has higher levels during extrauterine life and peak during puberty. The expression of IGF-BP3 in fibroblasts is stimulated by mitogenic growth factors such as Bombesin, Vasopressin, PDGF, and EGF. The protein forms a ternary complex with IGF-I or II and acid-labile subunit. In this form, it circulates in the plasma, prolonging the half-life of IGFs and altering their interaction with cell surface receptors. Decreased plasma levels of IGF-BP3 often happen during the progression of prostate cancer from benign to metastatic disease.