• Purity

  >95%, 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 activate Tie-2 in C6 rat glial cells transfected with human Tie-2. 0.2 μg/mL of Biotinylated Recombinant Human Angiopoietin-2 significantly induces phosphorylation of human Tie-2.

• Source

  Mouse myeloma cell line, NS0-derived Tyr19-Phe496, with a C-terminal 6-his tag

• Accession #

• N-terminal Sequence    
  Analysis

  Tyr19

• Structure / Form

  Oligomer, biotinylated via sugar residues    
   

• Predicted Molecular Mass

  56 kDa (unlabeled)

Carrier Free

What does CF mean?

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.

What formulation is right for me?

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: Angiopoietin-2

Angiopoietin-2 (Ang-2; also ANGPT2) is a secreted glycoprotein that plays a complex role in angiogenesis and inflammation (1, 2). Mature human Ang-2 is 478 amino acids (aa) in length. It contains one coiled-coil domain (aa 166-248) that mediates multimerization, and a C-terminal fibrinogen-like domain (aa 275-495) that mediates receptor binding. Under reducing conditions, secreted monomeric Ang-2 is 65-66 kDa in size. Under non-reducing conditions, both natural and recombinant Ang-2 form 140 kDa dimers, 200 kDa trimers, and 250-300 kDa tetramers and pentamers (3-5). Alternative splicing generates a short isoform that lacks 52 amino acids (aa) preceding the coiled-coil domain (6). Mature human Ang-2 shares 86% aa sequence identity with mouse and rat Ang-2. Ang-2 is widely expressed during development, but it is restricted postnatally to highly angiogenic tissues such as the placenta, ovaries, and uterus (3). It is particularly abundant in vascular endothelial cells (EC) where it is stored in intracellular Weibel-Palade bodies (1, 3, 7). Both Ang-2 and the related Angiopoietin-1 (Ang-1) are ligands for the receptor tyrosine kinase Tie-2 (2). While Ang-1 is a potent Tie-2 agonist, Ang-2 may act as either a Tie-2 antagonist or agonist, depending upon its state of multimerization. The higher the order of oligomer, the more effective Ang-2 becomes as a Tie-2 agonist (3, 8-11). The short isoform appears to block the binding of either Ang-1 or full-length Ang-2 to Tie-2 (5). Ang-2 functions as a pro-angiogenic factor, although it can also induce EC death and vessel regression (12, 13). Upon its release from quiescent EC, it regulates vascular remodeling by promoting EC survival, proliferation, and migration and destabilizing the interaction between EC and perivascular cells (8, 13, 14). Ang-2 is required for postnatal vascular remodeling, and it cooperates with Ang-1 during lymphatic vessel development (7, 15). It mediates the up-regulation of ICAM-1 and VCAM-1 on EC, which facilitates the adhesion of leukocytes during inflammation (16). Ang-2 is up-regulated in both the endothelium and tumor cells of several cancers as well as in ischemic tissue (17-20). Its direct interaction with Integrins promotes tumor cell invasion (21, 22). Ang-2 also promotes the neuronal differentiation and migration of subventricular zone progenitor cells (20).

• References:

1. Augustin, H.G. et al. (2009) Nat. Rev. Mol. Cell Biol. 10:165.

2. Murdoch, C. et al. (2007) J. Immunol. 178:7405.

3. Maisonpierre, P.C. et al. (1997) Science 27:55.

4. Procopio, W.N. et al. (1999) J. Biol. Chem. 274:30196.

5. Kim, K-T. et al. (2005) J. Biol. Chem. 280:20126.

6. Kim, I. et al. (2000) J. Biol. Chem. 275:18550.

7. Gale, N.W. et al. (2002) Dev. Cell 3:411.

8. Yuan, H.T. et al. (2009) Mol. Cell. Biol. 29:2011.

9. Falcon, B.L. et al. (2009) Am. J. Pathol. 175:2159.

10. Kim, H-Z. et al. (2009) Biochim. Biophys. Acta 1793:772.

11. Kim, I. et al. (2001) Cardiovasc. Res. 49:872.

12. Lobov, I.B. et al. (2002) Proc. Natl. Acad. Sci. 99:11205.

13. Cao, Y. et al. (2007) Cancer Res. 67:3835.

14. Nasarre, P. et al. (2009) Cancer Res. 69:1324.

15. Dellinger, M. et al. (2008) Dev. Biol. 319:309.

16. Fiedler, U. et al. (2006) Nat. Med. 12:235.

17. Koga, K. et al. (2001) Cancer Res. 61:6248.

18. Etoh, T. et al. (2001) Cancer Res. 61:2145.

19. Tressel, S.L. et al. (2008) Arterioscler. Thromb. Vasc. Biol. 28:1989.

20. Liu, X.S. et al. (2009) J. Biol. Chem. 284:22680.

21. Hu, B. et al. (2006) Cancer Res. 66:775.

22. Imanishi, Y. et al. (2007) Cancer Res. 67:4254.

• Entrez Gene IDs:

  285 (Human); 11601 (Mouse)

• Alternate Names:

  AGPT2; ANG2; ANG-2; angiopoietin 2; Angiopoietin-2; angiopoietin-2a; angiopoietin-2B; angiopoitin 2; ANGPT2; Tie2-ligand