S6 Kinase Substrate (229-239), AKRRRLSSLRA

AKRRRLSSLRA corresponds to residues 229-239 of ribosomal protein S6 and is a widely used serine/threonine kinase substrate. Published studies have used this peptide to measure p70 S6 kinase, p90 ribosomal S6 kinase and Rho-kinase activity. Because several kinases can phosphorylate the basic S6-derived sequence, it is best treated as a versatile kinase substrate rather than an isozyme-specific reagent.

• S6 kinase activity assays
• Rho-kinase activity measurements
• serine/threonine kinase inhibitor screening
• phosphorylation kinetics

The peptide contains adjacent serines within the phosphorylation region. Enzyme identity and phosphorylation site should be established with appropriate controls when assay specificity is important.

1. Kinetic mechanism for human Rho-Kinase II (ROCK-II)
2. The Activated Glucocorticoid Receptor Modulates Presumptive Autoregulation of Ribosomal Protein S6 Protein Kinase, p70 S6K