Figure 1. Treatment of A-431 cells with EGF stimulates phosphorylation of GSK-3α at Ser21 but does not affect the level of total GSK-3α. The relationship between lysate protein concentration from untreated and EGF-treated A-431 cells and the absorbance at 450 nm using the FastScan™ Phospho-GSK-3α (Ser21) #41165 is shown in the upper figure. The corresponding western blots using phospho-GSK-3α (Ser21) antibody (left panel) and total GSK-3α antibody (right panel) are shown in the lower figure. After serum starvation, A-431 cells were treated with 100 ng/ml EGF #8916 for 5 minutes at 37°C and then lysed.
|REACTIVITY||H M R Mk|
|Product Includes||Volume (with Count)||Solution Color|
|FastScan™ ELISA Microwell Strip Plate, 96 Well 53257||1 x 96 tests|
|GSK-3α Rabbit Capture mAb||1 x 1 ea||Green (Lyophilized)|
|Phospho-GSK-3α (Ser21) Rabbit HRP-linked mAb||1 x 1 ea||Red (Lyophilized)|
|FastScan™ ELISA Capture Antibody Diluent||1 x 3 ml||Green|
|FastScan™ ELISA HRP Antibody Diluent||1 x 3 ml|
|TMB Substrate 7004||1 x 11 ml|
|STOP Solution 7002||1 x 11 ml|
|Sealing Tape||1 x 1 ea|
|ELISA Wash Buffer (20X) 9801||1 x 25 ml|
|FastScan™ ELISA Cell Extraction Buffer (5X) 69905||1 x 10 ml|
|FastScan™ ELISA Cell Extraction Enhancer Solution (50X) 25243||1 x 1 ml|
|FastScan™ ELISA Kit #41165 Positive Control||2 x 1 ea|
NOTE: Prepare solutions with deionized/purified water or equivalent.
Prepare only as much reagent as needed on the day of the experiment.
*IMPORTANT: The provided FastScan™ ELISA Cell Extraction Enhancer Solution (50X) may precipitate when stored at 4°C. To dissolve, warm briefly at 37°C and mix gently. The FastScan™ ELISA Cell Extraction Enhancer Solution (50X) can be stored at room temperature to avoid precipitation.
NOTE: The 1X Cell Extraction Buffer contains phosphatase inhibitors. Protease inhibitors should be added to the 1X Cell Extraction Buffer immediately prior to lysing cells. Additional phosphatase inhibitors can also be added (e.g. Protease/Phosphatase Inhibitor Cocktail (100X) #5872, not supplied).
For adherent cells
For suspension cells
NOTE: Equilibrate all materials and prepared reagents to room temperature prior to running the assay.
*NOTE: Certain FastScan™ ELISA Kits may require additional washes at this step. Any requirements for additional washes will be specifically noted in the product “Description” of the kit’s datasheet.
NOTE: Initial color of positive reaction is blue, which changes to yellow upon addition of STOP Solution.
posted May 2018
revised November 2018
Protocol Id: 1704
The FastScan™ Phospho-GSK-3α (Ser21) ELISA Kit is a sandwich enzyme-linked immunosorbent assay (ELISA) that detects endogenous levels of GSK-3α when phosphorylated at Ser21. To perform the assay, sample is incubated with a capture antibody conjugated with a proprietary tag and a second detection antibody linked to HRP, forming a sandwich with phospho-GSK-3α (Ser21) in solution. This entire complex is immobilized to the plate via an anti-tag antibody. The wells are then washed to remove unbound material. TMB is then added. The magnitude of observed signal is proportional to the quantity of phospho-GSK-3α (Ser21). Antibodies in kit are custom formulations specific to kit.
The FastScan™ Phospho-GSK-3α (Ser21) ELISA Kit detects endogenous levels of GSK-3α when phosphorylated at Ser21 as shown in Figure 1. This kit detects proteins from the indicated species, as determined through in-house testing, but may also detect homologous proteins from other species.
Human, Mouse, Rat, Monkey
Glycogen synthase kinase-3 (GSK-3) was initially identified as an enzyme that regulates glycogen synthesis in response to insulin (1). GSK-3 is a ubiquitously expressed serine/threonine protein kinase that phosphorylates and inactivates glycogen synthase. GSK-3 is a critical downstream element of the PI3K/Akt cell survival pathway whose activity can be inhibited by Akt-mediated phosphorylation at Ser21 of GSK-3α and Ser9 of GSK-3β (2,3). GSK-3 has been implicated in the regulation of cell fate in Dictyostelium and is a component of the Wnt signaling pathway required for Drosophila, Xenopus, and mammalian development (4). GSK-3 has been shown to regulate cyclin D1 proteolysis and subcellular localization (5).
Explore pathways + proteins related to this product.
Cell Signaling Technology is a trademark of Cell Signaling Technology, Inc.
FastScan™ ELISA is a trademark of Cell Signaling Technology, Inc.
U.S. Patents 9,086,407, 9,261,500, and 9,476,874, foreign equivalents, and child patents deriving therefrom.