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PhosphoSitePlus® Resource

  • Additional protein information
  • Analytical tools


Product Includes Quantity Applications Reactivity MW(kDa) Isotype
COX IV (3E11) Rabbit mAb (HRP Conjugate) 5247 20 µl
Western Blotting
H R Mk Z B Pg 17 Rabbit IgG
β-Tubulin (9F3) Rabbit mAb (HRP Conjugate) 5346 20 µl
Western Blotting
H M R Mk Z B 55 Rabbit IgG
GAPDH (D16H11) XP® Rabbit mAb (HRP Conjugate) 8884 20 µl
Western Blotting
H M R Mk 37 Rabbit IgG
β-Actin (D6A8) Rabbit mAb (HRP Conjugate) 12620 20 µl
Western Blotting
H M R Mk Dm Z 45 Rabbit IgG
Histone H3 (D1H2) XP® Rabbit mAb (HRP Conjugate) 12648 20 µl
Western Blotting
H M R Mk 17 Rabbit IgG

Product Usage Information


Product Description

The Loading Control Antibody Sampler Kit (HRP Conjugate) contains antibodies directed against a variety of housekeeping proteins. These Cell Signaling Technology antibodies are conjugated to the carbohydrate groups of horseradish peroxidase (HRP) via its amine groups. The kit contains enough primary antibodies to perform two western blots.

Specificity / Sensitivity

Each antibody in the Loading Control Antibody Sampler Kit (HRP Conjugate) detects endogenous levels of its target protein and does not typically cross-react with other proteins. Histone H3 (D1H2) XP® Rabbit mAb (HRP Conjugate) detects endogenous levels of total histone H3 protein, including the Histone H3 variant CENP-A.

Source / Purification

Monoclonal antibodies are produced by immunizing animals with synthetic peptides corresponding to residues near the amino terminus of human β-actin, surrounding Lys29 of human COX IV, near the carboxy terminus of human GAPDH, near the carboxy terminus of human histone H3, and near the amino terminus of human β-tubulin.

Housekeeping proteins perform numerous basic functions within the cell and are constitutively expressed at high levels in a variety of tissues and cell types. Western blot analysis commonly uses housekeeping proteins such as β-actin, COX IV, GAPDH, histone H3 and the α- and β-tubulins as loading controls. Actin is a ubiquitous protein and a major component of the eukaryotic cytoskeleton. Actin exists mainly as the F-actin fibrous polymer (1). Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) catalyzes the phosphorylation of glyceraldehyde-3-phosphate during glycolysis. Recent work has demonstrated that GAPDH plays roles in apoptosis (2), gene expression (3), and nuclear transport (4). Globular tubulin subunits made up of α- and β-tubulin heterodimers are the building blocks of microtubules, one of three types of cytosolic fibers that comprise the cytoskeleton (5). Histone proteins, including histone H3, make up the primary building block of chromatin known as nucleosomes. Modulation of the chromatin structure plays an important role in the regulation of transcription in eukaryotes (6). Cytochrome c oxidase (COX) is a hetero-oligomeric enzyme consisting of 13 subunits localized to the inner mitochondrial membrane (7-9). It is the terminal enzyme complex in the respiratory chain, catalyzing the reduction of protons across the mitochondrial inner membrane to drive ATP synthesis (10).

1.  Workman, J.L. and Kingston, R.E. (1998) Annu Rev Biochem 67, 545-79.

2.  Condeelis, J. (2001) Trends Cell Biol 11, 288-93.

3.  Hara, M.R. and Snyder, S.H. (2006) Cell Mol. Neurobiol. 26, 527-38.

4.  Westermann, S. and Weber, K. (2003) Nat Rev Mol Cell Biol 4, 938-47.

5.  Capaldi, R.A. et al. (1983) Biochim. Biophys. Acta 726, 135-148.

6.  Zheng, L. et al. (2003) Cell 114, 255-66.

7.  Ostermeier, C. et al. (1996) Curr. Opin. Struct. Biol. 6, 460-466.

8.  Kadenbach, B. et al. (2000) Free Radic. Biol. Med. 29, 211-221.

9.  Bae, B.I. et al. (2006) Proc. Natl. Acad. Sci. USA 103, 3405-9.

10.  Barrientos, A. et al. (2002) Gene 286, 53-63.

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.

Loading Control Antibody Sampler Kit (HRP Conjugate)