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Product Includes Quantity Applications Reactivity MW(kDa) Isotype
GST (91G1) Rabbit mAb 2625 40 µl
All Rabbit 
Myc-Tag (71D10) Rabbit mAb 2278 40 µl
Rabbit IgG
HA-Tag (C29F4) Rabbit mAb 3724 40 µl
All Rabbit IgG
His-Tag (D3I1O) XP® Rabbit mAb 12698 40 µl
All Rabbit IgG
DYKDDDDK Tag (9A3) Mouse mAb (Binds to same epitope as Sigma's Anti-FLAG® M2 Antibody) 8146 40 µl
Mouse IgG1
Anti-rabbit IgG, HRP-linked Antibody 7074 100 µl
All Goat 
Anti-mouse IgG, HRP-linked Antibody 7076 100 µl
All Horse 

Product Description

The Epitope Tag Antibody Sampler Kit provides an economical means to analyze the expression of a variety of epitope tagged proteins. The kit contains enough primary and secondary antibodies to perform four Western blots per primary antibody.

Specificity / Sensitivity

All antibodies in the Epitope Tag Antibody Sampler Kit detect overexpressed fusion proteins containing the corresponding epitope tags. DYKDDDDK Tag Antibody recognizes the DYKDDDDK peptide (the same epitope recognized by Sigma’s Anti-FLAG® antibodies), and its binding specificity is NOT dependent on the presence of divalent metal cations.

Source / Purification

Rabbit monoclonal antibodies are producted by immunizing rabbits with a GST fusion protein, a synthetic peptide corresponding to residues 410-419 of human c-Myc (EQKLISEEDL), residues of the 6xHis epitope tag, or with a synthetic peptide containing the influenza hemagglutinin epitope (YPYDVPDYA). Mouse monoclonal antibodies are produced by immunizing animals with a synthetic DYKDDDDK peptide. Polyclonal antibodies are produced by immunizing rabbits with a synthetic DYKDDDDK peptide. Polyclonal antibodies are purified by protein A and peptide affinity chromatography.

Epitope tags are useful for the labeling and detection of proteins using immunoblotting, immunoprecipitation, and immunostaining techniques. Because of their small size, they are unlikely to affect the tagged protein's biochemical properties.

Several different epitope tags are now commonly utilized and readily available. For instance, a variety of plasmids contain DNA that encodes an amino-terminal tag consisting of six histidine (6xHis) residues followed by an extended multiple cloning site. The 6xHis tag on the expressed recombinant proteins allows for efficient coupling to Ni2+ affinity resins and purification by single step chromatography (1). As is the case with other protein tag systems (2), this polyhistidine tag can often be cleaved at sites recognized by proteases such as thrombin and enterokinases to isolate the protein of interest (1). Glutathione S-transferase (GST) is another widely used fusion partner, since it provides both an easily detectable Tag and a simple purification process with little effect on the biological function of the protein of interest. Numerous vectors containing GST-Tag have been developed for both prokaryotic and eukaryotic systems over the past decade (3-5). The HA tag, derived from an epitope of the influenza hemagglutinin protein, has also been extensively used as a general epitope tag in expression vectors (6), while the Myc epitope tag is routinely used to detect expression of recombinant proteins in bacteria, yeast, insect and mammalian cell systems (7). Finally, the DYKDDDDK peptide has been used extensively as a general epitope tag in expression vectors and consists of only eight amino acids. This peptide can be expressed and detected with the protein of interested as an amino-terminal or carboxy-terminal fusion (8).

1.  Kroll, D.J. et al. (1993) DNA Cell Biol 12, 441-53.

2.  Field, J. et al. (1988) Mol Cell Biol 8, 2159-65.

3.  di Guan, C. et al. (1988) Gene 67, 21-30.

4.  Guan, K.L. and Dixon, J.E. (1991) Anal Biochem 192, 262-7.

5.  Davis, A.H. et al. (1993) Biotechnology 11, 933-936.

6.  Yu, J. et al. (1998) Mol Cell Biol 18, 1379-87.

7.  Munro, S. and Pelham, H.R. (1984) EMBO J 3, 3087-93.

8.  Brizzard, B.L. et al. (1994) Biotechniques 16, 730-5.

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. 5,675,063.