• Purity

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

• Endotoxin Level

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

• Activity

  Measured by its ability to induce CXCL1/KC secretion by C3H10T1/2 mouse embryonic fibroblast cells. The ED    ₅₀ for this effect is 0.8-4 μg/mL.    
   

• Source

  E. coli-derived Thr2-Pro114

• Accession #

• N-terminal Sequence    
  Analysis

  Thr2

• Predicted Molecular Mass

  13 kDa

• SDS-PAGE

  12 kDa, reducing conditions

Data Images

Background: S100A9

S100A9, also known as MRP14 and Calgranulin B, is an approximately 14 kDa pro-inflammatory protein in the S100 family of calcium binding proteins (1, 2). It is  
up-regulated in neutrophils and monocytes at sites of inflammation (e.g. psoriasis, rheumatoid arthritis, cardiac ischemia) and is present at elevated concentrations in rheumatoid arthritis synovial fluid (3-6). Human S100A9 contains two EF-hand calcium binding motifs and shares 57% and 62% amino acid sequence identity with mouse and rat S100A9, respectively (7). S100A9 is a noncovalent homodimer that can also noncovalently heterodimerize with S100A8; in the presence of calcium and zinc, the homodimer and heterodimers will form tetramers (8-10). Human S100A9 can be phosphorylated at Thr113 near the C-terminus, a residue which is not conserved in the mouse protein (11). Human S100A9 can also be modified by S-glutathionylation and oxidation (12). The S100A8/A9 heterodimer binds to fatty acids such as arachidonic acid, while neither monomer does (4). S100A9 and the heterodimer promote neutrophil infiltration and degranulation at sites of inflammation and inflammatory cytokine production by monocytes (5, 6, 9, 13). S100A9 also promotes cartilage matrix destruction in osteoarthritis (14) as well as RAGE-dependent cardiac fibrosis and remodeling (6). In the brain, the S100A9 homodimer promotes neuronal cytotoxicity, although this is reduced by its binding to amyloid-beta peptide (15).

• References:

1. Averill, M.M. et al. (2012) Arterioscler. Thromb. Vasc. Biol. 32:223.

2. Vogl, T. et al. (2012) Int. J. Mol. Sci. 13:2893.

3. Edgeworth, J. et al. (1991) J. Biol. Chem. 266:7706.

4. Siegenthaler, G. et al. (1997) J. Biol. Chem. 272:9371.

5. Sunahori, K. et al. (2006) Arthritis Res. Ther. 8:R69.

6. Volz, H.C. et al. (2012) Basic Res. Cardiol. 107:250.

7. Odink, K. et al. (1987) Nature 330:80.

8. Teigelkamp, S. et al. (1991) J. Biol. Chem. 266:13462.

9. Ryckman, C. et al. (2003) J. Immunol. 170:3233.

10. Vogl, T. et al. (2006) Biochim. Biophys. Acta 1763:1298.

11. Edgeworth, J. et al. (1989) Nature 342:189.

12. Lim, S.Y. et al. (2010) J. Biol. Chem. 285:14377.

13. Simard, J.-C. et al. (2010) J. Leukoc. Biol. 87:905.

14. Schelbergen, R.F.P. et al. (2012) Arthritis Rheum. 64:1477.

15. Zhang, C. et al. (2012) PLoS ONE 7:e32953.

• Long Name:

  S100 Calcium Binding Protein A9

• Entrez Gene IDs:

  6280 (Human); 20202 (Mouse)

• Alternate Names:

  CAGBMigration inhibitory factor-related protein 14; Calgranulin B; calgranulin-B; Calprotectin L1H subunit; CFAGMRP-14,60B8AG; CGLB; L1AG; LIAG; MAC387; MIF; MRP-14; MRP14Leukocyte L1 complex heavy chain; NIF; P14; protein S100-A9; S100 calcium binding protein A9 (calgranulin B); S100 calcium binding protein A9; S100 calcium-binding protein A9 (calgranulin B); S100 calcium-binding protein A9; S100A9