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PhosphoSitePlus® Resource

  • Additional protein information
  • Analytical tools


Product Includes Quantity Applications Reactivity MW(kDa) Isotype
Calnexin (C5C9) Rabbit mAb 2679 20 µl
Western Blotting Immunohistochemistry Immunofluorescence
H Mk 90 Rabbit 
ERp72 (D70D12) XP® Rabbit mAb 5033 20 µl
Western Blotting Immunofluorescence Flow Cytometry
H M R Mk 72 Rabbit IgG
PDI (C81H6) Rabbit mAb 3501 20 µl
Western Blotting Immunohistochemistry Immunofluorescence
H M R Mk 57 Rabbit 
RCAS1 (D2B6N) XP® Rabbit mAb 12290 20 µl
Western Blotting Immunoprecipitation Immunofluorescence Flow Cytometry
H M R 32 Rabbit IgG
Syntaxin 6 (C34B2) Rabbit mAb 2869 20 µl
Western Blotting Immunoprecipitation Immunofluorescence
H M R 32 Rabbit IgG
Anti-rabbit IgG, HRP-linked Antibody 7074 100 µl
Western Blotting

Product Description

The ER and Golgi-Associated Marker Proteins Antibody Sampler Kit contains reagents to examine proteins that help regulate protein folding and vesicle trafficking. This kit includes enough antibody to perform two western blot experiments with each primary antibody.

Specificity / Sensitivity

Each antibody will detect endogenous total levels of their target protein.

Source / Purification

Monoclonal antibodies are produced by immunizing animals with a synthetic peptide corresponding to the sequence of human calnexin, the sequence of human PDI, the residues surrounding Met279 of human ERp72 protein, the residues surrounding Gly147 of human RCAS1 protein, and the residues surrounding Tyr140 of mouse syntaxin 6 protein.

Secretory and transmembrane proteins are synthesized on polysomes and translocate into the endoplasmic reticulum (ER) where they are often modified by the formation of disulfide bonds, amino-linked glycosylation, and folding. The ER contains a pool of molecular chaperones to help proteins fold properly. Calnexin is a calcium-binding, ER membrane protein that ensures proper protein folding by retaining newly synthesized glycoproteins within the ER l (1-3). The specificity of calnexin for a subset of glycoproteins is defined by a lectin site, which binds an early oligosaccharide intermediate on the folding glycoprotein (3). Many secretory proteins require the formation of intra- or inter-molecular disulfide bonds to reach their native conformation (4). Protein disulfide isomerase (PDI) catalyzes the formation and isomerization of disulfide bonds during oxidative protein folding (5). The ER-protein Ero1 oxidizes PDI through disulfide exchange, which is followed by PDI-catalyzed disulfide bond formation in folding proteins (6). The ER stress protein 72 (ERp72) contains three thioredoxin homology domains and plays a role in the formation and isomerization of disulfide bonds (7,8).

The tumor-associated antigen RCAS1 negatively regulates cytotoxic T lymphocyte (CTL) cytolytic activity, which impacts vesicle formation, secretion, and protein glycosylation (9-12). Overexpression of RCAS1 impairs CTL cytolytic function by negatively regulating trans-Golgi to secretory lysosome protein trafficking, leading to a delay in ER to Golgi vesicle transport and mislocalization of ER quality control and glycosylation proteins. As a result, RCAS1 induces deposition of tumor-associated glycan antigens on the cell surface, which may contribute to tumor pathogenesis through the mediation of adhesion, invasion, and metastasis (13,14). Syntaxin 6 is a ubiquitously expressed S25C family member of the SNARE proteins (15,16) that is localized to the trans-Golgi and within endosomes. It regulates membrane trafficking by partnering with a variety of other SNARE proteins (17-19) and is involved in the regulation of GLUT4 trafficking, neutrophil exocytosis, and granule secretion (20-22).

1.  Rajagopalan, S. et al. (1994) Science 263, 387-90.

2.  Bergeron, J.J. et al. (1994) Trends Biochem. Sci. 19, 124-128.

3.  Rüder, C. et al. (2009) J Clin Invest 119, 2184-203.

4.  Williams, D.B. (2006) J. Cell Sci. 119, 615-623.

5.  Huppa, J.B. and Ploegh, H.L. (1998) Cell 92, 145-8.

6.  Ellgaard, L. and Ruddock, L.W. (2005) EMBO Rep. 6, 28-32.

7.  Tu, B.P. and Weissman, J.S. (2004) J Cell Biol 164, 341-6.

8.  Mazzarella, RA et al. (1990) J Biol Chem 265(2), 1094-101.

9.  Reimer, T.A. et al. (2005) BMC Cancer 5, 47.

10.  Satoh, M et al. (2005) Cell Stress Chaperones 10(4), 278-84

11.  Wolf, J. et al. (2010) FASEB J 24, 4000-19.

12.  Engelsberg, A. et al. (2003) J Biol Chem 278, 22998-3007.

13.  Bock, J.B. et al. (2001) Nature 409, 839-41.

14.  Bock, J.B. et al. (1996) J Biol Chem 271, 17961-5.

15.  Wendler, F. and Tooze, S. (2001) Traffic 2, 606-11.

16.  Bock, J.B. et al. (1997) Mol Biol Cell 8, 1261-71.

17.  Mallard, F. et al. (2002) J Cell Biol 156, 653-64.

18.  Perera, H.K. et al. (2003) Mol Biol Cell 14, 2946-58.

19.  Shewan, A.M. et al. (2003) Mol Biol Cell 14, 973-86.

20.  Martín-Martín, B. et al. (2000) Blood 96, 2574-83.

21.  Wendler, F. et al. (2001) Mol Biol Cell 12, 1699-709.

22.  Kuliawat, R. et al. (2004) Mol Biol Cell 15, 1690-701.

For Research Use Only. Not For Use In Diagnostic Procedures.
Cell Signaling Technology is a trademark of Cell Signaling Technology, Inc.

ER and Golgi-Associated Marker Proteins Antibody Sampler Kit