Figure 1. Jurkat cells express significantly higher levels of phospho-Rb (Ser780) compared with HeLa cells. The relationship between lysate protein concentration from Jurkat and HeLa cells and the absorbance at 450 nm as detected by FastScan™ Phospho-Rb (Ser780) ELISA Kit #97258 is shown in the upper figure. The corresponding western blots using a phospho-Rb (Ser780) antibody (left panel) and an actin antibody (right panel) are shown in the lower figure.
|Product Includes||Volume (with Count)||Solution Color|
|FastScan™ ELISA Microwell Strip Plate, 96 Well 53257||1 x 96 tests|
|Rb Rabbit Capture mAb||1 x 1 ea||Green (Lyophilized)|
|Phospho-Rb (Ser780) 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 #97258 Positive Control Type 1||1 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).
NOTE: A select number of FastScan™ ELISA kits do not contain a positive control, please refer to Product Includes table on the datasheet for a list of included reagents. Should you need support on how to generate a positive control for those kits, contact CST technical support at firstname.lastname@example.org.
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 2019
Protocol Id: 1924
The FastScan™ Phospho-Rb (Ser780) ELISA Kit is a sandwich enzyme-linked immunosorbent assay (ELISA) that detects endogenous levels of Rb when phosphorylated at Ser780. 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-Rb (Ser780) 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-Rb (Ser780). Antibodies in kit are custom formulations specific to kit.
The FastScan™ Phospho-Rb (Ser780) ELISA Kit detects endogenous levels of Rb when phosphorylated at Ser780, 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.Species Reactivity:
The retinoblastoma tumor suppressor protein Rb regulates cell proliferation by controlling progression through the restriction point within the G1-phase of the cell cycle (1). Rb has three functionally distinct binding domains and interacts with critical regulatory proteins including the E2F family of transcription factors, c-Abl tyrosine kinase, and proteins with a conserved LXCXE motif (2-4). Cell cycle-dependent phosphorylation by a CDK inhibits Rb target binding and allows cell cycle progression (5). Rb inactivation and subsequent cell cycle progression likely requires an initial phosphorylation by cyclin D-CDK4/6 followed by cyclin E-CDK2 phosphorylation (6). Specificity of different CDK/cyclin complexes has been observed in vitro (6-8) and cyclin D1 is required for Ser780 phosphorylation in vivo (9).
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. Patent No. 7,429,487, foreign equivalents, and child patents deriving therefrom.
U.S. Patents 9,086,407, 9,261,500, and 9,476,874, foreign equivalents, and child patents deriving therefrom.