CST, 9121S, Phospho-MEK1/2 (Ser217/221) Antibody

Polyclonal Antibody for studying MEK2 (Ser222/Ser226) phosphate/MEK1 (Ser218/Ser222) phosphate. Validated for Western Blotting,Immunoprecipitation. Available in 2 sizes. Highly specific and rigorously validated in-house, Phospho-MEK1/2 (Ser217/221) Antibody (CST #9121) is ready to ship. Product Usage Information Western Blotting: 1:1000 Immunoprecipitation: 1:50 Storage Supplied in 10 mM sodium HEPES (pH 7.5), 150 mM NaCl, 100 µg/ml BSA and 50% glycerol. Store at -20°C. Do not aliquot the antibody. Protocol Available protocols: Western Blotting, Immunoprecipitation Specificity / Sensitivity Phospho-MEK1/2 (Ser217/221) Antibody detects endogenous levels of MEK1/2 only when activated by phosphorylation at Ser217/221. This antibody does not cross-react with related kinases including activated SEK (MKK4), MKK3 or MKK6. This antibody will also react with MEK1/2 singly phosphorylated at Ser217 and singly phosphorylated at Ser221. Species Reactivity: Human, Mouse, Rat, Monkey, S. cerevisiae Source / Purification Polyclonal antibodies are produced by immunizing animals with a synthetic phosphopeptide corresponding to residues around Ser217/221 of human MEK1/2. Antibodies are purified by protein A and peptide affinity chromatography. Background 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. CST's Phospho- MEK1/2 (Ser217/221) Antibody selectively recognizes active MEK, i.e., only when phosphorylated at Ser217/221, and hence is an excellent marker of MEK1/2 activity. Alternate Names CFC3; CFC4; Dual specificity mitogen-activated protein kinase kinase 1; Dual specificity mitogen-activated protein kinase kinase 2; ERK activator kinase 1; ERK activator kinase 2; FLJ26075; MAP kinase kinase 1; MAP kinase kinase 2; MAP2K1; MAP2K2; MAPK/ERK kinase 1; MAPK/ERK kinase 2; MAPKK 1; MAPKK 2; MAPKK1; MAPKK2; MEK 1; MEK 2; MEK1; MEK2; MEL; mitogen-activated protein kinase kinase 1; mitogen-activated protein kinase kinase 2; mitogen-activated protein kinase kinase 2, p45; MKK1; MKK2; MP2K1; MP2K2; PRKMK1; PRKMK2; protein kinase, mitogen-activated, kinase 1 (MAP kinase kinase 1) Specification REACTIVITY: H M R Mk Sc SENSITIVITY: Endogenous MW (kDa): 45 SOURCE: Rabbit