• Purity

  >95%, by SDS-PAGE under reducing conditions and visualized by silver stain

• Endotoxin Level

  <1.0 EU per 1 μg of the protein by the LAL method.  

• Activity

  Measured by its ability to inhibit the biological activity of IGF-I or IGF-II on MCF?7 human breast cancer cells. Karey, K.P.     et al. (1988) Cancer Research     48:4083. The ED    ₅₀ for this effect is 0.03?0.09 μg/mL in the presence of 14 ng/mL rhIGF-II.

• Source

  Mouse myeloma cell line, NS0-derived Glu40-Gln328, with an N-terminal Met

• Accession #

• N-terminal Sequence    
  Analysis

  Met

• Predicted Molecular Mass

  31 kDa

• SDS-PAGE

  36 kDa, reducing conditions

Background: IGFBP-2

The superfamily of insulin-like growth factor (IGF) binding proteins include the six high-affinity IGF binding proteins (IGFBP) and at least four additional low-affinity binding proteins referred to as IGFBP related proteins (IGFBP-rP). All IGFBP superfamily members are cysteine-rich proteins with conserved cysteine residues, which are clustered in the amino- and carboxy-terminal thirds of the molecule. IGFBPs modulate the biological activities of IGF proteins. Some IGFBPs may also have intrinsic bioactivity that is independent of their ability to bind IGF proteins. Post-translational modifications of IGFBPs, including glycosylation, phosphorylation and proteolysis, have been shown to modify the affinities of the binding proteins to IGF.

Human IGFBP-2 cDNA encodes a 328 amino acid (aa) residue precursor protein with a putative 39 aa residue signal peptide that is processed to generate the 289 aa residue mature protein. IGFBP-2 contains an integrin receptor recognition sequence (RGD sequence) but lacks potential N-linked glycosylation sites. During development, IGFBP-2 is expressed in a number of tissues. The highest expression level is found in the central nervous system. In adults, high expression levels are also detected in the central nervous system and in a number of reproductive tissues. IGFBP-2 binds preferentially to IGF II, exhibiting a 2 - 10 fold higher affinity for IGF II than for IGF I.

• References:

1. Jones, J.I. and D.R. Clemmons (1995) Endocrine Rev. 16:3.

2. Kelley, K.M. et al. (1996) Int. J. Biochem. Cell Biol. 28:619.

• Long Name:

  Insulin-like Growth Factor Binding Protein 2

• Entrez Gene IDs:

  3485 (Human); 16008 (Mouse)

• Alternate Names:

  BP2; IBP2; IBP-2; IGF-binding protein 2; IGFBP2; IGFBP-2; IGF-BP53; insulin-like growth factor binding protein 2 (36kD); insulin-like growth factor binding protein 2, 36kDa; insulin-like growth factor-binding protein 2