• Purity

  >90%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie? Blue Staining.

• Endotoxin Level

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

• Activity

  Measured by its binding ability in a functional ELISA. Immobilized rhIGF-II R at 2 μg/mL (100 μL/well) can bind rhIGF-II with a linear range of 2-100 ng/mL.

• Source

  Mouse myeloma cell line, NS0-derived Ser1510-Phe2108, with a C-terminal 6-His tag

• Accession #

• N-terminal Sequence    
  Analysis

  Ser1510

• Predicted Molecular Mass

  67 kDa

• SDS-PAGE

  80-83 kDa, reducing conditions

Background: IGF-II R

The type 2 insulin-like growth factor receptor (also known as cation-independent mannose-6 phosphate receptor/CI-MPR) is a 300 kDa member of the P-type lectin family of molecules. P-type lectins generate functional eukaryotic lysosomes by binding and sorting lysosomal enzymes expressing phosphorylated mannose residues (M6P) (1-3). IGF-II R is a type I transmembrane glycoprotein that contains a 2,264 amino acid (aa) extracellular region, a 23 aa transmembrane segment and a 124 aa cytoplasmic tail (4, 5). The extracellular region consists of 15 contiguous “binding” repeats of about 150 aa each. The odd-numbered repeats interact with “l(fā)igands” while the even-numbered repeats likely generate a nondisulfide homodimer in the membrane (1). Repeat #11 binds IGF-II, while repeats 3 and 9 bind mannose-6 phosphate; repeat #13 contains a fibronectin type II motif and assists in IGF-II binding (1, 2). In the extracellular region of IGF-II R expressed by R&D Systems (600 aa’s), human IGF-II R is 85% aa identical to both mouse and bovine IGF-II R. This expressed region includes binding repeats #11, 12, and 13. In addition to IGF-II, CI-MPR/IGF-II R binds non-M6P containing ligands such as retinoic acid, urokinase-type plasminogen-activator receptor and plasminogen, plus
M6P-containing molecules such as lysosomal enzymes, TGF-beta 1 precursor, proliferin, LIF, CD26, herpes simplex glycoprotein D and granzymes A and B (2, 6). IGF-II R regulates many diverse biological functions that range from intracellular trafficking to the internalization of extracellular factors and modulation of cellular responses. It delivers newly synthesized M6P-tagged lysosomal enzymes from the trans-golgi network to endosomes, and facilitates the clearance of extracellular lysosomal and matrix degrading enzymes by internalization into clathrin-coated vesicles and delivery into endosomes. With respect to IGF-II biology, it would appear that IGF-II R is principally a regulator of local IGF-II levels, targeting IGF-II for destruction in lysosomes (2). However, some evidence suggests the receptor will signal via G-proteins, an effect that has yet to be conclusively shown (6).

• References:

1. Ghosh, P. et al. (2003) Nat. Rev. Mol. Cell. Biol. 4:202.

2. Dahms, N.M. and M.K. Hancock (2002) Biochim. Biophys. Acta. 1572:317.

3. Zaina, S. and J. Nilsson (2003) Curr. Opin. Lipidol. 14:483.

4. Morgan, D.O. et al. (1987) Nature 329:301.

5. Oshima, A. et al. (1988) J. Biol. Chem. 263:2553.

6. Hawkes, C. and S. Kar (2004) Brain Res. Rev. 44:117.

• Long Name:

  Insulin-like Growth Factor II Receptor

• Entrez Gene IDs:

  3482 (Human)

• Alternate Names:

  300 kDa mannose 6-phosphate receptor; cation-independent mannose-6 phosphate receptor; cation-independent mannose-6-phosphate receptor; CD222 antigen; CD222; CI Man-6-P receptor; CIMPR; CI-MPR; IGF2R; IGF-II R; IGF-II receptor; IGFIIR; IGF-IIR; insulin-like growth factor 2 receptorM6P/IGF2R; Insulin-like growth factor II receptor; M6P/IGF2 receptor; M6PR; M6P-R; MPR 300; MPR1; MPRI; MPRIM6PR