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PTMScan® Motif Antibody Kits
New Format-Same Price

Now 10 Assays Per Kit

Order Now

Pricing & Additional Information

To learn more about our Proteomics Kits and Services, including pricing, please answer a few questions for our proteomics group.

Contact the CST Proteomics Group  


Find answers on our FAQs page.


PhosphoSitePlus® Resource

  • Additional protein information
  • Analytical tools


Product Includes Cap Color Volume (with Count)
PTMScan® IAP Buffer (10X) 9993 White 10 x 600 µl
PTMScan(R) Phospho-Thr-X-Arg Motif [pT(P/X)R] IAP Beads Blue 10 x 80 µl
PTMScan® Limited Use License 1 x  license

Product Usage Information

Cells are lysed in a urea-containing buffer, cellular proteins are digested by proteases, and the resulting peptides are purified by reversed-phase solid-phase extraction. Peptides are then subjected to immunoaffinity purification using a PTMScan® Motif Antibody conjugated to protein A agarose beads. Unbound peptides are removed through washing, and the captured PTM-containing peptides are eluted with dilute acid. Reversed-phase purification is performed on microtips to desalt and separate peptides from antibody prior to concentrating the enriched peptides for LC-MS/MS analysis. CST recommends the use of PTMScan® IAP Buffer #9993 included in the kit. A detailed protocol and Limited Use License allowing the use of the patented PTMScan® method are included with the kit.

Storage: Antibody beads supplied in IAP buffer containing 50% glycerol. Store at -20°C. Do not aliquot the antibody.

Product Description

PTMScan® Technology employs a proprietary methodology from Cell Signaling Technology (CST) for peptide enrichment by immunoprecipitation using a specific bead-conjugated antibody in conjunction with liquid chromatography (LC) tandem mass spectrometry (MS/MS) for quantitative profiling of post-translational modification (PTM) sites in cellular proteins. These include phosphorylation (PhosphoScan®), ubiquitination (UbiScan®), acetylation (AcetylScan®), and methylation (MethylScan®), among others. PTMScan® Technology enables researchers to isolate, identify, and quantitate large numbers of post-translationally modified cellular peptides with a high degree of specificity and sensitivity, providing a global overview of PTMs in cell and tissue samples without preconceived biases about where these modified sites occur. For more information on PTMScan® Proteomics Services, please visit

The MAPK and CDK families of serine/threonine protein kinases play important roles in proliferation and cell cycle control. These kinases phosphorylate threonine or serine residues that are followed by a proline residue (1-3). MAPK phosphorylates substrates with the consensus sequence PX(S/T)P and CDKs phosphorylate substrates containing the consensus sequence (S/T)PXR/K (4,5). Some signaling molecules can be regulated by phosphorylation at a specific threonine followed by an arginine or lysine at the +2 position. For example, conventional PKC isozymes phosphorylate substrates containing a serine or threonine with Arg or Lys at the -3, -2 and +2 positions (6,7). Cell Signaling Technology has developed antibodies that bind to phosphorylation sites containing the T(P/X)R motif for discovery and proteome-wide profiling of kinase substrates.

1.  Cross, T.G. et al. (2000) Exp Cell Res 256, 34-41.

2.  Pearson, R.B. and Kemp, B.E. (1991) Methods Enzymol 200, 62-81.

3.  Reynolds, C.H. et al. (2000) J Neurochem 74, 1587-95.

4.  Seger, R. and Krebs, E.G. (1995) FASEB J 9, 726-35.

5.  Songyang, Z. et al. (1996) Mol Cell Biol 16, 6486-93.

6.  Holmes, J.K. and Solomon, M.J. (1996) J Biol Chem 271, 25240-6.

7.  Nishikawa, K. et al. (1997) J Biol Chem 272, 952-60.

For Research Use Only. Not For Use In Diagnostic Procedures.
AcetylScan is a trademark of Cell Signaling Technology, Inc.
Cell Signaling Technology is a trademark of Cell Signaling Technology, Inc.
MethylScan is a trademark of Cell Signaling Technology, Inc.
PhosphoScan is a trademark of Cell Signaling Technology, Inc.
PTMScan is a trademark of Cell Signaling Technology, Inc.
UbiScan is a trademark of Cell Signaling Technology, Inc.

PTMScan® Phospho-Thr-X-Arg Motif [pT(P/X)R] Kit