Merck, 05-1085, Anti-IRS1 Antibody, clone 4.2.2

General description
IRS1 (Insulin Receptor Substrate 1) transmits insulin signals via metabolic and mitogenic pathways. IRS1 is heavily phosphorylated on both serine and tyrosine residues. These phosphorylated tyrosines enable IRS to act as a docking protein that binds SH2 domains of such proteins as PI3 Kinase (phosphatidylinositol 3-kinase) and GRB2, resulting in activation. Over expression and phosphorylation of serine is associated with insulin resistance and breast cancer. Some of the more notable phosphorylation sites are Ser302 that is phosphorylated following insulin stimulation. Ser307, phosphorylated by JNK and IKK, is a key regulatory site that appears to disrupt the IRS1/IR interaction and inhibits insulin-mediated activation of the PI3 kinase and MAPK pathways, and Ser636/639 that is known to be phosphorylated by p70S6K downstream of mTOR and acts as a negative feedback loop.
~185 kDa
Immunogen
Synthetic peptide corresponding to amino acids 431-446 of mouse IRS1.
Application
This Anti-IRS1 Antibody, clone 4.2.2 is validated for use in WB, IP, IC for the detection of IRS1.
Biochem/physiol Actions
Predicted to cross-react with many other species based on 100% sequence homology with immunogen.
This antibody recognizes IRS1.
Physical form
Format: Purified
Purified mouse monoclonal antibody in buffer containing 0.1 M Tris-Glycine (pH 7.4),150 mM NaCl with 0.05% sodium azide.
Analysis Note
Evaluated by western blot on IR/IRS1 transfected CHO +/- Insulin lysate.

Western Blot Analysis:
1:1,000 dilution of this antibody was used to detect IRS1 in IRS/IR transfected CHO -/+ Calyculin A/ Okadaic Acid-treated cell lysate.

Other Notes
Concentration: Please refer to the Certificate of Analysis for the lot-specific concentration.