Recombinant Human IGFBP-3 Protein, CF

Recombinant Human IGFBP-3 Protein, CF Summary

Product Specifications

Product Datasheets

Carrier Free

CF stands for Carrier Free (CF). We typically add Bovine Serum Albumin (BSA) as a carrier protein to our recombinant proteins. Adding a carrier protein enhances protein stability, increases shelf-life, and allows the recombinant protein to be stored at a more dilute concentration. The carrier free version does not contain BSA.

In general, we advise purchasing the recombinant protein with BSA for use in cell or tissue culture, or as an ELISA standard. In contrast, the carrier free protein is recommended for applications, in which the presence of BSA could interfere.

Background: IGFBP-3

Insulin-like growth factor binding protein-3 (IGFBP-3) is one of six members of the insulin­like growth factor (IGF) binding protein superfamily which function to modulate the biological activity of IGF (1). Human IGFBP-3 is the major binding protein of IGF where it exists in circulation as a ternary complex with the acid-labile subunit (ALS) (2). Like other IGFBP members, human IGFBP-3 includes a cysteine-rich C-terminal domain, a highly variable central linker domain, and another
N-terminal cystein-e­rich domain (2, 3). Human IGFBP­-3 cDNA encodes a 291 amino acid (aa) precursor protein with a 27 aa signal peptide that is processed to generate the 264 aa mature protein. Mature human IGFBP-3 shares 82% aa sequence identity with both mouse and rat IGFBP-3. Post­translational glycosylation and phosphorylation of IGFBP-3 modifies the affinities of the binding protein. Proteolysis of IGFBP-3 by tissue plasminogen activator (tPA), a disintegrin and metaloproteases (ADAMs), and prostate specific antigen (PSA) contributes to IGFBP-3 degradation or a reduction in its affinity for IGF (4-6). The majority of soluble IGFBP-3 found in circulation is secreted from hepatic non-parenchymal cells. IGFBP-3 expression can be modulated by p53 as well as by various cytokines and growth factors (7, 8). In addition to its role in stabilizing and transporting circulating IGF, IGFBP-3 has been shown to potentiate EGF-EGFR-mediated cell growth through the activation of sphingosine kinase1 (SPHK1) and sphingosin-1-phosphate (S1P) (9, 10). IGFBP-3 has also been shown to modulate adipogenesis (11). Binding of IGFBP-3 to non-IGF-related ligands has been shown to regulate TGF-beta signaling, DNA damage, apoptosis, autophagy, and gene transcription (12). Interactions with non-IGF-related ligands is thought to contribute, in part, to the dichotomous stimulatory and inhibitory effects of IGFBP-3 on cell growth (2).

Related Research Areas

• Cancer Biomarkers
• HIF Transcription Factors
• IGF Family
• Metabolic Peptide Hormones and Regulators
• Osteoblast and Osteoclast Markers
• Osteoblast Markers
• Osteogenesis Markers