Phospho-CDK2 (Tyr15) Cellular Kit
Simple and robust detection kit for Phospho-CDK2 (Tyr15)
The Total CDK6 cellular assay monitors CDK6 protein levels.
CDK6 (Cyclin-Dependent Kinase 6) is a member of the subfamily of CDKs that coordinate cell cycle progression in mammalian cells (also including CDK1, CDK2, and CDK4). In the early G1 phase of the cell cycle, CDK6 is activated by interaction with Cyclin D and mono-phosphorylates the tumor suppressor RB (protein of retinoblastoma), leading to the transcription of genes required for G1/S phase transition.
Dysregulated activation of CDK6, leading to uncontrolled cell division, is a hallmark of cancers. Inhibition of CDK6 is thus an active research area, especially since the emergence of new approaches involving PROTACs (PROteolysis TArgeting Chimeras).
The Total CDK6 assay quantifies the expression level of CDK6 in a cell lysate. Unlike Western Blot, the assay is entirely plate-based and does not require gels, electrophoresis, or transfer. The Total CDK6 assay uses two labeled antibodies, one coupled to a donor fluorophore and the other to an acceptor. Both antibodies are highly specific for a distinct epitope on the protein. In the presence of CDK6 in a cell extract, the addition of these conjugates brings the donor fluorophore into close proximity with the acceptor and thereby generates a FRET signal. Its intensity is directly proportional to the concentration of the protein present in the sample, and provides a means of assessing the protein's expression under a no-wash assay format.
Detection of Total CDK6 with HTRF reagents can be performed in a single plate used for culturing, stimulation, and lysis. No washing steps are required. This HTS designed protocol enables miniaturization while maintaining robust HTRF quality.
HeLa and HEK293 cells were plated in 96-well plates (40,000 and 50,000 cells/well respectively) and cultured for 24h. The cells were then transfected with siRNAs specific for CDK1, CDK2, CDK4, or CDK6, as well as with a negative control siRNA. After 48h incubation, the cells were lyzed and 16 µL of lysates were transferred into a 384-well low volume white microplate before the addition of 4 µL of the HTRF Total CDK2, Total CDK4, or Total CDK6 detection antibodies. The HTRF signal was recorded after an overnight incubation.
Cell transfection with each specific CDK2, CDK4, or CDK6 siRNA led to a 77 to 97% signal decrease compared to the cells transfected with the negative siRNA. It should be noted that the small signal decrease observed on the total CDK6 assay when cells were transfected with CDK2 siRNA was expected, since CDK2 knockdown leads to down-regulation of CDK6 (Bačević et al., Sci Rep. 2017; 7: 13429). Taken together, these data demonstrate that HTRF Total CDK2, Total CDK4, and Total CDK6 assays are specific for each kinase and do not cross-react with other cell cycle CDK family members.
HEK293 cells were cultured in a T175 flask in complete culture medium at 37°C-5% CO2. After 48h incubation, the cells were lysed with 3 mL of supplemented lysis buffer #1 (1X) for 30 minutes at RT under gentle shaking.
Serial dilutions of the cell lysate were performed using supplemented lysis buffer, and 16 µL of each dilution were transferred into a low volume white microplate before the addition of 4 µL of HTRF total CDK6 detection reagents. Equal amounts of lysates were used for a side by side comparison between HTRF and Western Blot.
Using the HTRF total CDK6 assay, 800 cells/well were enough to detect a significant signal, while 1,600 cells were needed to obtain a minimal chemiluminescent signal using Western Blot. Therefore in these conditions, the HTRF total CDK6 assay was twice as sensitive as the Western Blot technique.
CDK6 (Cyclin-Dependent Kinase 6) is a member of the subfamily of CDKs that coordinate cell cycle progression in mammalian cells (also including CDK1, CDK2, and CDK4).
Mitogenic signals, such as growth factors, trigger cells to enter the G1 phase of the cell cycle by inducing cyclin D synthesis. Cyclin D then interacts with CDK4 and CDK6 to form active complexes. Both activated kinases are then able to mono-phosphorylate the tumor suppressor RB (protein of retinoblastoma), which still binds to transcription factor E2F, but some genes can be transcribed, such as cyclin E. In the late G1 and early S phases, Cyclin E interacts with and activates CDK2, which in turn phosphorylates additional sites on RB resulting in its complete inactivation. The E2F-responsive genes required for S phase progression are thus induced, such as Cyclin A which then interacts with CDK2 to form Cyclin A/CDK2 complexes. CDK2 finally phosphorylates Cdc25B & Cdc25C phosphatases, which in turn activate CDK1, required for progression in the G2 and M phases of the cell-division cycle.
Physiologically relevant results fo fast flowing research - Flyers
Insider Tips for successful sample treatment - Technical Notes
HTRF and WB compatible guidelines - Technical Notes
Our offer for PROTAC research summarized in this flyer - Flyers
Mastering the art of cell signaling assays optimization - Guides
Streamlined set-up and access to multiple read-out options for research in oncology - Application Notes
A solution for phospho-protein analysis in metabolic disorders - Posters
Detailed protocol and direct comparison with WB - Posters
A single technology for 2D cells, 3D cells, and xenograft models - Posters
PI3K/AKT/mTor translational control pathway - Posters
Analysis of a large panel of diverse biological samples and cellular models - Posters
One technology across all samples - Application Notes
Tumor xenograft analysis: HTRF versus Western blot - Application Notes
Valuable guidelines for efficiently analyzing and interpreting results - Application Notes
Increased flexibility of phospho-assays - Application Notes
Analyse of PI3K/AKT/mTor translational control pathway - Application Notes
In collaboration with Bayer - Scientific Presentations
A fun video introducing you to phosphorylation assays with HTRF - Videos
Get the brochure about technology comparison. - Brochures
Protocol for tumor xenograft analysis with HTRF - Technical Notes
Multi-tissue cellular modeling and anlysis of insulin signaling - Posters
Seeding and lysing recommendations for a number of cell culture vessels. - Technical Notes
Combination of AlphaLISA®, HTRF®, or AlphaLISA® SureFire® Ultra™ immunoassays with the ATPlite™ 1step cell viability assay - Application Notes
Learn how to reduce time and sample consumption - Application Notes
Choosing the right microplate reader ensures you’ll get an optimal readout. Discover our high performance reader, or verify if your lab equipment is going to be compatible with this detection technology.Let's find your reader