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Santa Cruz discontinued a large number of its polyclonal products as a result of the USDA settlement that was made public May 19th 2016

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9120S 1 Kit (10 western blots) $503.00.0


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PhosphoSitePlus® Resource

  • Additional protein information
  • Analytical tools


Western blot analysis of extracts from untreated or TPA-treated HeLa and NIH/3T3 cells, using Phospho-MEK1/2 (Ser217/221) (41G9) Rabbit mAb (upper), or MEK1/2 Antibody #9122 (lower).

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Western blot analysis of extracts from various cell lines using MEK1/2 (D1A5) Rabbit mAb.

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Western blot analysis of extracts from Hela cells, untreated or TPA-treated, using Phospho-MEK1/2 (Ser217/221) (41G9) RmAb #9154 (upper) or MEK1/2 (D1A5) Rabbit mAb #8727 (lower).

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After the primary antibody is bound to the target protein, a complex with HRP-linked secondary antibody is formed. The LumiGLO® is added and emits light during enzyme catalyzed decomposition.

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Flow cytometric analysis of Jurkat cells using MEK1/2 (D1A5) Rabbit mAb (blue) compared to Rabbit (DA1E) mAb IgG XP® Isotype Control #3900 (red).

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Confocal immunofluorescent analysis of HeLa cells using MEK1/2 (D1A5) Rabbit mAb (green). Actin filaments were labeled with DY-554 phalloidin. Blue pseudocolor = DRAQ5® #4084 (fluorescent DNA dye).

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Product Includes Quantity Applications Reactivity MW(kDa) Isotype
Phospho-MEK1/2 (Ser217/221) (41G9) Rabbit mAb 9154 100 µl
Western Blotting Immunoprecipitation
H M R Mk Dm 45 Rabbit 
MEK1/2 (D1A5) Rabbit mAb 8727 100 µl
Western Blotting Immunofluorescence Flow Cytometry
H M R Mk Dm 45 Rabbit IgG
MEK1/2 HeLa Control Cell Extracts 9160 200 µl
Western Blotting
Anti-rabbit IgG, HRP-linked Antibody 7074 100 µl
Western Blotting
Anti-biotin, HRP-linked Antibody 7075 100 µl
Western Blotting
All Goat 
20X LumiGLO® Reagent and 20X Peroxide 7003 5 ml each
Western Blotting
Biotinylated Protein Ladder Detection Pack 7727 100 µl

Product Usage Information


Product Description

The PhosphoPlus® MEK1/2 (Ser217/221) Antibody Kit provides reagents and protocols for the rapid analysis of the phosphorylation status of MEK1/2 at Ser217/221.

Specificity / Sensitivity

Phospho-MEK1/2 (Ser217/221) Antibody detects endogenous levels of MEK1/2 only when phosphorylated at serines 217 and 221. It will also react with MEK1/2 singly phosphorylated at Ser217 and singly phosphorylated at Ser221. MEK1/2 (D1A5) Rabbit mAb recognizes endogenous levels of total MEK1 and MEK2 proteins.

Source / Purification

Monoclonal antibodies are produced by immunizing animals with a synthetic phosphopeptide corresponding to residues around Ser217/221 of human MEK1/2 and synthetic peptide corresponding to residues surrounding Ala220 of human MEK1 protein.

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.
PhosphoPlus is a trademark of Cell Signaling Technology, Inc.
LumiGLO is a registered trademark of Kirkegaard & Perry Laboratories.
U.S. Patent No. 5,675,063.

PhosphoPlus® MEK1/2 (Ser217/221) Antibody Kit