• Purity

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

• Endotoxin Level

  <0.10 EU per 1 μg of the protein by the LAL method.  

• Activity

  Measured by its binding ability in a functional ELISA. When biotinylated recombinant mouse Wnt-3a (25 ng/mL, 100 μL/well) is captured on streptavidin-coated plate, Recombinant Human Glypican 6 binds with an apparent K    _d <10 nM.  

• Source

  Mouse myeloma cell line, NS0-derived Asp24-Arg354 & Ser355-Val527, with a C-terminal 6-His tag

• Accession #

• N-terminal Sequence    
  Analysis

  Asp24 & Ser355    
   

• Predicted Molecular Mass

  38 kDa and 20 kDa

• SDS-PAGE

  38 kDa and 27-29 kDa, reducing conditions

Background: Glypican 6

The Glypicans (glypiated proteoglycans) are a small multigene family of GPI-linked heparan sulfate (HS) proteoglycans that likely play a key role in embryonic morphogenesis (1, 2, 3, 4). There are currently six known mammalian Glypicans. They all share a common-sized protein core of 60 - 70 kDa, an N-terminus which likely forms a compact globular domain, 14 conserved cysteines that form multiple intrachain disulfide bonds, and a number of C-terminal N- and O-linked carbohydrate attachment sites. Based on exon organization and the location of O-linked glycosylation sites, at least two subfamilies of Glypicans are known, with one subfamily containing Glypicans 1, 2, 4 and 6, and another subfamily containing Glypicans 3 and 5 (3, 5). Human Glypican 6 (GPC-6) is synthesized as a 554 amino acid (aa) preproprecursor that contains a 23 aa signal sequence, a 505 aa mature region and a 26 aa C-terminal prosegment (5, 6). There are four consecutive Ser-Gly repeats that serve as a heparin sulfate attachment site. GPC-6 is reported to be as large as 110 kDa in size. This translates into approximately 50 kDa of proteoglycan (5). Human to mouse, there is 97% aa identity over the entire GPC-6 molecule. Cells known to express GPC-6 are adult ovary and embryonic vascular and visceral smooth muscle, plus mesenchyme (embryonic connective tissue) in multiple organs (1, 5, 6). The function of GPC-6 is essentially unknown. As a Glypican family member, it may facilitate heparin-binding growth factor signaling and polyamine uptake into expressing cells (7, 8). In this regard, it would appear that GPC-6 with its attendant HS is downregulated by triiodothyronine during cartilage maturation, thus limiting the availability of sites for FGF sequestration and activity (9).

• References:

1. Song, H.H. and J. Filmus (2002) Biochim. Biophys. Acta 1573:241. 

2. Filmus, J. (2001) Glycobiology 11:19R. 

3. De Cat, B. and G. David (2001) Semin. Cell Dev. Biol. 12:117. 

4. Filmus, J. (2003) Glycoconj. J. 19:319. 

5. Veugelers, M. et al. (1999) J. Biol. Chem. 274:26968.

6. Paine-Saunders, S. et al. (1999) Genomics 57:455.

7. Fransson, L-A. et al. (2004) Cell Mol. Life Sci. 61:1016.

8. Fransson, L-A. (2003) Int. J. Biochem. Cell Biol. 35:125.

9. Bassett, J.H.D. et al. (2006) Endocrinology 147:295.

• Entrez Gene IDs:

  10082 (Human); 23888 (Mouse)

• Alternate Names:

  Glypican 6; glypican proteoglycan 6; glypican-6; GPC6; MGC126288; OMIMD1