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Product Includes Quantity Applications Reactivity MW(kDa) Isotype
Phospho-IRS-1 (Ser307) Antibody 2381 40 µl
H M R 180 Rabbit 
Phospho-IRS-1 (Ser612) (C15H5) Rabbit mAb 3203 40 µl
H M R 180 Rabbit IgG
IRS-2 Antibody 4502 40 µl
H M R 185 Rabbit 
Phospho-IRS-1 (Ser318) (D51C3) Rabbit mAb 5610 40 µl
H M 180 Rabbit IgG
IRS-1 (D23G12) Rabbit mAb 3407 40 µl
H M R Mk 180 Rabbit IgG
Anti-rabbit IgG, HRP-linked Antibody 7074 100 µl
All Goat 

Product Description

The Insulin Receptor Substrate Antibody Sampler Kit provides an economical means to investigate IRS-1 and IRS-2 signaling and phosphorylation within the cell. The kit contains enough antibody to perform four western blots with each primary antibody.

Specificity / Sensitivity

Phospho-IRS-1 (Ser307) Antibody, Phospho-IRS-1 (Ser612) (C15H5) Rabbit mAb and Phospho-IRS-1 (Ser318) Antibody detect endogenous levels of IRS-1 only when phosphorylated at Ser307, Ser612 or Ser318, respectively. Note: Ser318 is the mouse residue; the corresponding human residue is Ser323. IRS-1 Antibody and IRS-2 Antibody detect endogenous levels of total IRS-1 or IRS-2, respectively. The Phospho-IRS-1 (Ser318) antibody cross reacts with a inducible nonspecific band at around 57 kDa.

Source / Purification

Polyclonal antibodies are produced by immunizing animals with a synthetic peptide corresponding to the carboxy-terminal sequence of human IRS-2 and residues surrounding Ser307 of mouse IRS-1 (homologous to Ser312 of human IRS-1). Polyclonal antibodies are purified by protein A and peptide affinity chromatography. Monoclonal antibodies are produced by immunizing animals with a synthetic phosphopeptide corresponding to residues surrounding Ser612 of mouse IRS-1, a synthetic peptide corresponding to the sequence surrounding Ser270 of human IRS-1 and a synthetic phosphopeptide corresponding to residues surrounding Ser318 of mouse IRS-1 protein.

Insulin receptor substrate 1 (IRS-1) is one of the major substrates of the insulin receptor kinase (1). IRS-1 contains multiple tyrosine phosphorylation motifs that serve as docking sites for SH2-domain containing proteins that mediate the metabolic and growth-promoting functions of insulin (2-4). IRS-1 also contains over 30 potential serine/threonine phosphorylation sites. Ser307 of IRS-1 is phosphorylated by JNK (5) and IKK (6) while Ser789 is phosphorylated by SIK-2, a member of the AMPK family (7). The PKC and mTOR pathways mediate phosphorylation of IRS-1 at Ser612 and Ser636/639, respectively (8,9). Phosphorylation of IRS-1 at Ser1101 is mediated by PKCθ and results in an inhibition of insulin signaling in the cell, suggesting a potential mechanism for insulin resistance in some models of obesity (10).

1.  Sun, X.J. et al. (1991) Nature 352, 73-7.

2.  Sun, X.J. et al. (1992) J Biol Chem 267, 22662-72.

3.  Myers, M.G. et al. (1993) Endocrinology 132, 1421-30.

4.  Wang, L.M. et al. (1993) Science 261, 1591-4.

5.  Rui, L. et al. (2001) J Clin Invest 107, 181-9.

6.  Horike, N. et al. (2003) J. Biol. Chem. 278, 18440-18447.

7.  Gao, Z. et al. (2002) J Biol Chem 277, 48115-21.

8.  Ozes, O.N. et al. (2001) Proc Natl Acad Sci U S A 98, 4640-5.

9.  De Fea, K. and Roth, R.A. (1997) Biochemistry 36, 12939-47.

10.  Li, Y. et al. (2004) J Biol Chem 279, 45304-7.

Entrez-Gene Id 3667, 8660
Swiss-Prot Acc. P35568, Q9Y4H2

For Research Use Only. Not For Use In Diagnostic Procedures.
Cell Signaling Technology® is a trademark of Cell Signaling Technology, Inc.
U.S. Patent No. 5,675,063.