Mitogen-activated protein kinase kinase 2 (MEK2), also known as MAP2K2, is a dual-specificity protein kinase in the MAPK/ERK signaling pathway. MEK2 phosphorylates and activates ERK1/2, which in turn regulates cell growth, differentiation, and survival. MEK2 is activated by upstream kinases such as RAF, which are often triggered by growth factors and other extracellular signals. Abnormal MEK2 activity is associated with certain cancers, including nearly all cutaneous melanomas. MEK2 is a target for therapeutic intervention in several cancers.
The AlphaLISA SureFire Ultra Human and Mouse Total MEK2 Detection Kit is a sandwich immunoassay for the quantitative detection of total MEK2 in cellular lysates, using Alpha Technology.
Formats:
The HV (high volume) kit contains reagents to run 100 wells in 96-well format, using a 60 μL reaction volume.
The 500-point kit contains enough reagents to run 500 wells in 384-well format, using a 20 μL reaction volume.
The 10,000-point kit contains enough reagents to run 10,000 wells in 384-well format, using a 20 μL reaction volume.
The 50,000-point kit contains enough reagents to run 50,000 wells in 384-well format, using a 20 μL reaction volume.
AlphaLISA SureFire Ultra kits are compatible with:
Cell and tissue lysates
Antibody modulators
Biotherapeutic antibodies
Alpha SureFire Ultra kits can be used for:
Cellular kinase assays
Receptor activation studies
Screening
Total-AlphaLISA SureFire Ultra assay principle
The Total-AlphaLISA SureFire Ultra assay measures the expression level of a target protein in a biological sample (e.g. cell lysate).
The Total-AlphaLISA SureFire Ultra assay uses two antibodies which recognize two different distal epitopes on the target protein. AlphaLISA assays require two bead types: Acceptor and Donor Beads. Acceptor Beads are coated with a proprietary CaptSure™ agent to specifically immobilize the assay specific antibody, labeled with a CaptSure tag. Donor Beads are coated with streptavidin to capture one of the detection antibodies, which is biotinylated. In the presence of target protein, the two antibodies bring the Donor and Acceptor Beads in close proximity whereby the singlet oxygen transfers energy to excite the Acceptor Bead, allowing for the generation of a luminescent Alpha signal. The amount of light emission is directly proportional to the quantity of protein present in the sample.
Total-AlphaLISA SureFire Ultra two-plate assay protocol
The two-plate protocol involves culturing and treating the cells in a 96-well plate before lysis, then transferring lysates into a 384-well OptiPlate™ plate before the addition of Total-AlphaLISA SureFire Ultra detection reagents. This protocol enables cell viability and confluence to be monitored. In addition, lysates from a single well can be used to measure multiple targets.
Total-AlphaLISA SureFire Ultra one-plate assay protocol
Detection of Total target protein with AlphaLISA SureFire Ultra reagents can be performed in a single plate used for culturing, treatment, and lysis. No washing steps are required. This HTS designed protocol allows for miniaturization while maintaining robust AlphaLISA SureFire Ultra quality.
Validation of Phospho (Ser217/221)/total MEK2 in EGF treated cells
HEK293 cells were seeded in a 96-well plate (60,000 cells/well) in complete medium, and incubated overnight at 37°C, 5% CO2. The cells were starved for 2 hours and then treated with increasing concentrations of EGF in serum free media for 10 minutes.
After treatment, the cells were lysed with 100 µL of Lysis Buffer for 10 minutes at RT with shaking (350 rpm). MEK2 Phospho (Ser217/221) and Total levels were evaluated using respective AlphaLISA SureFire Ultra assays. For the detection step, 10 µL of cell lysate (approximately 6,000 cells) was transferred into a 384-well white OptiPlate, followed by 5 µL of Acceptor mix and incubated for 1 hour at RT. Finally, 5 µL of Donor mix was then added to each well and incubated for 1 hour at RT in the dark. The plate was read on an Envision using standard AlphaLISA settings.
As expected, EGF triggered a dose-dependent increase in the levels of Phospho MEK2 (Ser217/221) while Total MEK2 levels remained unchanged.
Validation of Phospho (Ser217/221)/total MEK2 in NRG1 treated cells
MCF7 cells were seeded in a 96-well plate (40,000 cells/well) in complete medium, and incubated overnight at 37°C, 5% CO2. The cells were starved for 2 hours and then treated with increasing concentrations of Neuregulin (NRG1) in serum free media for 10 minutes.
After treatment, the cells were lysed with 100 µL of Lysis Buffer for 10 minutes at RT with shaking (350 rpm). MEK2 Phospho (Ser217/221) and Total levels were evaluated using respective AlphaLISA SureFire Ultra assays. For the detection step, 10 µL of cell lysate (approximately 4,000 cells) was transferred into a 384-well white OptiPlate, followed by 5 µL of Acceptor mix and incubated for 1 hour at RT. Finally, 5 µL of Donor mix was then added to each well and incubated for 1 hour at RT in the dark. The plate was read on an Envision using standard AlphaLISA settings.
As expected, NRG1 triggered a dose-dependent increase in the levels of Phospho MEK2 (Ser217/221) while Total MEK2 levels remained unchanged.
Validation of Phospho (Ser217/221)/total MEK2 in anti-CD3 treated cells
Jurkat cells were washed and resuspended in HBSS + 0.1% BSA at a density of 2x106 cells/mL, then seeded in a 96-well plate (200 µL per well). The cells were starved for 1 hour and then treated with increasing concentrations of anti-CD3 antibody in HBSS + 0.1% BSA for 5 minutes.
After treatment, the cells were lysed with 50 µL 5X Lysis Buffer for 10 minutes at RT with shaking (350 rpm). MEK2 Phospho (Ser217/221) and Total levels were evaluated using respective AlphaLISA SureFire Ultra assays. For the detection step, 10 µL of cell lysate (approximately 8,000 cells) was transferred into a 384-well white OptiPlate, followed by 5 µL of Acceptor mix and incubated for 1 hour at RT. Finally, 5 µL of Donor mix was then added to each well and incubated for 1 hour at RT in the dark. The plate was read on an Envision using standard AlphaLISA settings.
As expected, anti-CD3 antibody triggered a dose-dependent increase in the levels of Phospho MEK2 (Ser217/221) while Total MEK2 levels remained unchanged.
Validation of Phospho (Ser217/221)/total MEK2 in AG1478 treated cells
A431 cells were seeded in a 96-well plate (40,000 cells/well) in complete medium, and incubated overnight at 37°C, 5% CO2. The cells were treated with increasing concentrations of AG1478 for 2 hours followed by treatment with 1 ng/mL EGF for 30 minutes.
After treatment, the cells were lysed with 100 µL of Lysis Buffer for 10 minutes at RT with shaking (350 rpm). MEK2 Phospho (Ser217/221) and Total levels were evaluated using respective AlphaLISA SureFire Ultra assays. For the detection step, 10 µL of cell lysate (approximately 4,000 cells) was transferred into a 384-well white OptiPlate, followed by 5 µL of Acceptor mix and incubated for 1 hour at RT. Finally, 5 µL of Donor mix was then added to each well and incubated for 1 hour at RT in the dark. The plate was read on an Envision using standard AlphaLISA settings.
As expected, AG1478 (EGFR inhibitor) triggered a dose-dependent decrease in the levels of Phospho MEK2 (Ser217/221) while Total MEK2 levels remained unchanged.
Specificity of total MEK2 assay - recombinant protein
Specificity of the Total MEK2 assay was assessed by assaying recombinant MEK1 and MEK2 proteins. Dilutions of recombinant human MEK1 and MEK2 proteins were prepared in Lysis Buffer. Total MEK2 levels were evaluated using the AlphaLISA SureFire Ultra assay.
For the detection step, 10 µL of protein was transferred into a 384-well white OptiPlate, followed by 5 µL of Acceptor mix and incubated for 1 hour at RT. Finally, 5 µL of Donor mix was then added to each well and incubated for 1 hour at RT in the dark. The plate was read on an Envision using standard AlphaLISA settings.
Total MEK2 assay was specific only to MEK2 recombinant protein with no signal detected with MEK1 recombinant protein. This result demonstrates the specificity of Total MEK2 AlphaLISA SureFire Ultra assay as these two proteins share more than 80% sequence identity.
Specificity of total MEK2 assay in knockout cells
Total MEK2 protein levels were assessed in HEK293T wild type (WT) and HEK293T MEK2 knockout (KO) (Abcam, ab266315) cells. Both cell lines, WT and KO, were seeded in a 96-well plate (40,000 cells/well) in complete medium, and incubated overnight at 37°C, 5% CO2.
The cells were lysed with 100 µL of Lysis Buffer for 10 minutes at RT with shaking (350 rpm). MEK2 Total levels were then evaluated using the AlphaLISA SureFire Ultra assay. For the detection step, 10 µL of cell lysate was transferred into a 384-well white OptiPlate, followed by 5 µL of Acceptor mix and incubated for 1 hour at RT. Finally, 5 µL of Donor mix was then added to each well and incubated for 1 hour at RT in the dark. The plate was read on an Envision using standard AlphaLISA settings.
As expected, Total MEK2 was only detected in the WT HEK293T cells but not in the MEK2 KO cell lines, demonstrating assay specificity.
