-
Synonyms
p70, Ribosomal protein S6 kinase beta-1
-
Alternative_names
p70, Ribosomal protein S6 kinase beta-1, Serine/threonine-protein kinase 14A
-
Description
Increases protein synthesis and cell proliferation
-
Recombinant
Yes
-
Source
Baculovirus (Sf9 insect cells)
-
Purity by SDS PAGE
≥90%
-
Assay
SDS-PAGE
-
Activity Specifications test method
132 nmol phosphate incorporated into S6K substrate peptide per minute per mg protein at 30°C for 15 minutes using a final concentration of 50 µM ATP (0.83 µCi/assay).
-
Molecular Weight
76.0 kDa
-
Storage Temp
-80°C
-
Shipping
dry ice
-
Shelf Life
12 months
-
Concentration
5µg/50 µl
-
Appearance
Liquid
-
Physical form description
Recombinant protein in storage buffer (50 mM Tris-HCl, pH 7.5, 150 mM NaCl, 0.25 mM DTT, 0.1 mM EGTA, 0.1 mM EDTA, 0.1 mM PMSF, 25% glycerol).
-
Background Information
Activation of cell growth leads to the multiple phosphorylation of 40S ribosomal protein S6. The kinase responsible for controlling this event is termed p70S6K (1). Northern blot analysis shows p70S6K to be ubiquitously expressed in human adult tissues. p70S6K is activated by serum stimulation, and the serum-induced activation is inhibited by wortmannin and rapamycin. p70S6k activity undergoes changes in the cell cycle and increases 20-fold in G1 cells released from G0 (2). The kinase is reactivated 10-fold when cells released from a nocodazole-induced metaphase block enter G1 of the next cell cycle. The immunosuppressive agent rapamycin induces inactivation of p70s6k with no effect on other mitogen-activated kinases (3). The principal target of rapamycin-induced p70s6k inactivation is T389 site on p70S6K, which is located in an unusual hydrophobic sequence outside the catalytic domain. Mutation of T389 to alanine ablates kinase activity, whereas mutation to glutamic acid confers constitutive kinase activity and rapamycin resistance. p70S6K activation by growth factor requires phosphorylation by various inputs on multiple sites (4). p70S6K activation requires sequential phosphorylations at proline-directed residues in the putative autoinhibitory pseudosubstrate domain, as well as threonine 389. Threonine 229, a site in the catalytic loop is phosphorylated by phosphoinositide-dependent kinase 1 (PDK-1). Activation of p70S6K requires a phosphoinositide 3-kinase (PI3-K)-dependent signal(s).
-
Handling
Centrifuge the vial prior to opening.
-
Usage
For Research Use Only! Not to be used in humans
-
