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PhosphoSitePlus® Resource

  • Additional protein information
  • Analytical tools


Product Includes Quantity Applications Reactivity MW(kDa) Isotype
BiP (C50B12) Rabbit mAb 3177 20 µl
Western Blotting Immunohistochemistry Flow Cytometry
H M 78 Rabbit IgG
Ero1-Lα Antibody 3264 20 µl
Western Blotting
H 60 Rabbit 
ERp44 (D17A6) XP® Rabbit mAb 3798 20 µl
Western Blotting Immunohistochemistry
H M R Mk 44 Rabbit IgG
ERp57 (G117) Antibody 2881 20 µl
Western Blotting
H M R 57 Rabbit 
ERp72 (D70D12) XP® Rabbit mAb 5033 20 µl
Western Blotting Immunofluorescence Flow Cytometry
H M R Mk 72 Rabbit IgG
Grp94 Antibody 2104 20 µl
Western Blotting
H M R Mk 100 Rabbit 
PDI (C81H6) Rabbit mAb 3501 20 µl
Western Blotting Immunohistochemistry Immunofluorescence
H M R Mk 57 Rabbit 
Anti-rabbit IgG, HRP-linked Antibody 7074 100 µl
Western Blotting

Product Description

The ER Protein Folding Antibody Sampler Kit contains reagents to investigate the initiation of translation within the cell. The kit contains enough primary and secondary antibodies to perform two Western blot experiments per primary antibody.

Specificity / Sensitivity

Each antibody in the ER Protein Folding Antibody Sampler Kit detects endogenous levels of its target protein.

Source / Purification

Monoclonal antibody is produced by immunizing animals with a synthetic phosphopeptide corresponding to residues surrounding Gly584 of human BiP, the sequence of human ERp44, the residues surrounding Met279 of human ERp72 protein and the sequence of human PD1. Polyclonal antibodies are produced by immunizing animals with a synthetic peptide corresponding to the sequences around Gly117 of human ERp57, Met622 of human Grp94 and Leu218 of human Ero1-Lα. Polyclonal antibodies are purified by protein A and peptide affinity chromatography.

After their synthesis, secretory proteins translocate into the endoplasmic reticulum (ER) where they are post-translationally modified and properly folded. To reach their native conformation, many secretory proteins require the formation of intra- or inter-molecular disulfide bonds (1). This process is called oxidative protein folding. Disulfide isomerase (PDI) catalyzes the formation and isomerization of these disulfide bonds (2). Studies on mechanisms of oxidative folding suggest that molecular oxygen oxidizes the ER-protein Ero1, which in turn oxidizes PDI through disulfide exchange (3). This event is then followed by PDI-catalyzed disulfide bond formation on folding proteins (3). Other ER resident proteins that possess the thioredoxin homology domains, including endoplasmic reticulum stress proteins 72, 57 and 44 (ERp72, ERp57 and ERp44), constitute the PDI family (4,5,6). The ER also contains a pool of molecular chaperones, including Grp94, to help proteins fold properly. Grp94 is a glucose-regulated protein (7) with sequence homology to Hsp90 (8). BiP is another chaperone whose synthesis is increased when protein folding is disturbed. BiP binds to misfolded proteins to prevent them from forming aggregates and assists in proper refolding (9).

1.  Lee, A.S. et al. (1981) Proc Natl Acad Sci U S A 78, 4922-5.

2.  Sorger, P.K. and Pelham, H.R. (1987) J Mol Biol 194, 341-4.

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

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

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

6.  Jessop, C.E. et al. (2007) EMBO J 26, 28-40.

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

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

9.  Kohno, K. et al. (1993) Mol Cell Biol 13, 877-90.

For Research Use Only. Not For Use In Diagnostic Procedures.
Cell Signaling Technology is a trademark of Cell Signaling Technology, Inc.
U.S. Patent No. 7,429,487, foreign equivalents, and child patents deriving therefrom.

ER Protein Folding Antibody Sampler Kit