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PhosphoSitePlus® Resource

  • Additional protein information
  • Analytical tools


Product Includes Volume Solution Color
MEK1 Mouse mAb Coated Microwells 96 tests
Phospho-MEK1/2 (Ser217/221) Rabbit Detection Antibody 1 ea Green (Lyophilized)
Anti-rabbit IgG, HRP-linked Antibody (ELISA Formulated) 1 ea Red (Lyophilized)
Detection Antibody Diluent 11 ml Green
HRP Diluent 11 ml Red
TMB Substrate 7004 11 ml
STOP Solution 7002 11 ml
ELISA Wash Buffer (20X) 25 ml
ELISA Sample Diluent 25 ml Blue
Sealing Tape 2 ea
Cell Lysis Buffer (10X) 9803 15 ml

Product Description

CST's PathScan® Phospho-MEK1 (Ser217/221) Sandwich ELISA Kit is a solid phase sandwich enzyme-linked immunosorbent assay (ELISA) that detects endogenous levels of Phospho-MEK1 (Ser217/221) protein. MEK1 Mouse mAb has been coated onto the microwells. After incubation with cell lysates, total MEK1 protein (phospho- and nonphospho-) is captured by the coated antibody. Following extensive washing, a Phospho-MEK1/2 Antibody is added to detect the captured phospho-MEK1 protein. Anti-rabbit IgG, HRP-linked antibody is then used to recognize the bound detection antibody. HRP substrate, TMB, is added to develop color. The magnitude of optical density for this developed color is proportional to the quantity of phospho-MEK1 protein.

Antibodies in kit are custom formulations specific to kit.

Specificity / Sensitivity

CST's PathScan® Phospho-MEK1 (Ser217/221) Sandwich ELISA Kit detects endogenous levels of phospho-MEK1 protein. A significant induction of MEK1 phosphorylation in PMA-treated NIH/3T3 cells can be detected using this kit, #7175. However, the level of total MEK1 protein detected by PathScan® Total MEK1 Sandwich ELISA Kit #7165 remains unchanged (Figure 1). This kit can also be used to detect phosphorylated MEK1 protein in human 293 cells. This kit detects proteins from the indicated species, as determined through in-house testing, but may also detect homologous proteins from other species.

MEK1 and MEK2, also called MAPK or Erk kinases, are dual-specificity protein kinases that function in a mitogen activated protein kinase cascade controlling cell growth and differentiation (1-3). Activation of MEK1 and MEK2 occurs through phosphorylation of two serine residues at positions 217 and 221, located in the activation loop of subdomain VIII, by Raf-like molecules. MEK1/2 is activated by a wide variety of growth factors and cytokines and also by membrane depolarization and calcium influx (1-4). Constitutively active forms of MEK1/2 are sufficient for the transformation of NIH/3T3 cells or the differentiation of PC-12 cells (4). MEK activates p44 and p42 MAP kinase by phosphorylating both threonine and tyrosine residues at sites located within the activation loop of kinase subdomain VIII.

1.  Crews, C.M. et al. (1992) Science 258, 478-480.

2.  Alessi, D.R. et al. (1994) EMBO J. 13, 1610-19.

3.  Rosen, L.B. et al. (1994) Neuron 12, 1207-21.

4.  Cowley, S. et al. (1994) Cell 77, 841-52.

Entrez-Gene Id 5604
Swiss-Prot Acc. Q02750

For Research Use Only. Not For Use In Diagnostic Procedures.
Cell Signaling Technology is a trademark of Cell Signaling Technology, Inc.
PathScan is a trademark of Cell Signaling Technology, Inc.

PathScan® Phospho-MEK1 (Ser217/221) Sandwich ELISA Kit