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PTMScan® Motif Antibody Kits
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Product Usage Information

Storage: Supplied in 10 mM sodium HEPES (pH 7.5), 150 mM NaCl, 100 µg/ml BSA and 50% glycerol. Store at –20°C. Do not aliquot the antibody.

Specificity / Sensitivity

Phospho-(Ser) CDKs Substrate Antibody detects phospho-serine in a (K/R)(S*)PX(K/R) motif. The antibody is phospho-specific but does not recognize phospho-serine in the absence of the CDK motif. The antibody does not cross-react with phospho-threonine- or phospho-tyrosine-containing peptides/proteins. (U.S. Patent No's.: 6,441,140; 6,982,318; 7,259,022; 7,344,714; U.S.S.N. 11,484,485; and all foreign equivalents.)

Source / Purification

Polyclonal antibodies are produced by immunizing animals with synthetic phospho-CDK substrate peptides . Antibodies are purified by protein A and peptide affinity chromatography.

Cyclin-dependent kinases (CDKs) are a family of Ser/Thr kinases that regulate cell-cycle transitions through their association and subsequent phosphorylation of targets in a strictly ordered fashion (1). The substrates for CDKs are proline-directed. The consensus amino acid sequence for CDK substrate is (K/R)(S*)PX(K/R), where X denotes any one of the 20 amino acids (2-4) and S* is the phosphorylation site. Phospho-CDK Substrate Motif [(K/H)pSP] MultiMab™ Rabbit mAb mix recognizes phosphorylated CDK substrates at their consensus motif, providing a powerful tool for CDK target discovery and characterization, as well as HTS drug screening for potential kinase regulators.

1.  Morgan, D.O. (1997) Annu Rev Cell Dev Biol 13, 261-91.

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

3.  Songyang, Z. (1999) Prog Biophys Mol Biol 71, 359-72.

4.  Holmes, J.K. and Solomon, M.J. (1996) J. Biol. Chem. 271, 25240-25246.

For Research Use Only. Not For Use In Diagnostic Procedures.
Cell Signaling Technology is a trademark of Cell Signaling Technology, Inc.
Use of Cell Signaling Technology (CST) Motif Antibodies within certain methods (e.g., U.S. Patents No. 7,198,896 and 7,300,753) may require a license from CST. For information regarding academic licensing terms please have your technology transfer office contact CST Legal Department at For information regarding commercial licensing terms please contact CST Pharma Services Department at

Phospho-(Ser) CDKs Substrate Antibody