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PhosphoSitePlus® Resource

  • Additional protein information
  • Analytical tools


Product Includes Quantity Applications Reactivity MW(kDa) Isotype
Phospho-S6 Ribosomal Protein (Ser235/236) (D57.2.2E) XP® Rabbit mAb 4858 20 µl
Western Blotting Immunohistochemistry Immunofluorescence Flow Cytometry
H M R Mk Mi Sc 32 Rabbit IgG
Phospho-S6 Ribosomal Protein (Ser240/244) (D68F8) XP® Rabbit mAb 5364 20 µl
Western Blotting Immunohistochemistry Immunofluorescence Flow Cytometry
H M R Mk 32 Rabbit IgG
Phospho-eIF4B (Ser422) Antibody 3591 20 µl
Western Blotting
H M R Mk 80 Rabbit 
Phospho-eEF2k (Ser366) Antibody 3691 20 µl
Western Blotting Immunoprecipitation
H R Mk 105 Rabbit 
Phospho-p70 S6 Kinase (Thr389) (108D2) Rabbit mAb 9234 20 µl
Western Blotting
H M R Mk 70, 85 Rabbit IgG
p70 S6 Kinase (49D7) Rabbit mAb 2708 20 µl
Western Blotting Immunohistochemistry
H M R Mk 70, 85 Rabbit 
Anti-rabbit IgG, HRP-linked Antibody 7074 100 µl
Western Blotting

Product Description

The p70 S6 Kinase Substrates Antibody Sampler Kit provides a fast and economical means of evaluating several substrates of p70 S6 Kinase. The kit contains enough primary and secondary antibody to perform two Western blot experiments.

Specificity / Sensitivity

Each antibody in the p70 S6 Kinase Substrates Antibody Sampler Kit detects endogenous levels of its target protein. p70 S6 Kinase (49D7) Antibody #2708 also recognizes p85 S6 Kinase. Phospho-p70 S6 Kinase (Thr389) (108D2) Rabbit mAb #9234 also detects p85 S6 Kinase when phosphorylated at Thr412 and possibly S6KII when phosphorylated at Thr401. The other antibodies in the kit do not cross react with other proteins.

Source / Purification

Antibodies are produced by immunizing animals with a synthetic peptide corresponding to residues surrounding the amino-terminus of human p70 S6 Kinase; and to synthetic phosphopeptides corresponding to residues surrounding Thr389 of human p70 S6 Kinase; Ser235 and 236 of human ribosomal protein; Ser240 and 244 of human ribosomal protein; Ser422 of human eIF4B; and Ser366 of human eEF2k. Polyclonal antibodies are purified by protein A and peptide affinity chromatography.

p70 S6 kinase is a mitogen activated Ser/Thr protein kinase that is required for cell growth and G1 cell cycle progression (1,2). p70 S6 kinase phosphorylates the S6 protein of the 40S ribosomal subunit and is involved in translational control of 5' oligopyrimidine tract mRNAs (1). Important S6 ribosomal protein phosphorylation sites include several residues (Ser235, Ser236, Ser240, Ser244) located wtihin a small, carboxy-terminal region of the S6 protein (3,4). p70 S6 kinase has been shown to phosphorylate eIF4B at the rapamycin-sensitive site Ser422 in vivo, and a Ser422Ala mutant of eIF4B shows diminished activity in an in vitro translation assay (5). Phosphorylation of eEF2K by p70 S6 kinase and p90RSK leads to inactivation of eEF2K (6), facilitating the dephosphorylation of eEF2 and thus promoting translation.

1.  Pullen, N. and Thomas, G. (1997) FEBS Lett 410, 78-82.

2.  Dufner, A. and Thomas, G. (1999) Exp Cell Res 253, 100-9.

3.  Ferrari, S. et al. (1991) J Biol Chem 266, 22770-5.

4.  Flotow, H. and Thomas, G. (1992) J Biol Chem 267, 3074-8.

5.  Raught, B. et al. (2004) EMBO J 23, 1761-9.

6.  Wang, X. et al. (2001) EMBO J 20, 4370-9.

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.

p70 S6 Kinase Substrates Antibody Sampler Kit