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PhosphoSitePlus® Resource

  • Additional protein information
  • Analytical tools


Product Includes Volume Solution Color
IRS-1 Rabbit mAb Coated Microwells 96 tests
Sealing Tape 2 sheets

Product Description

The PathScan® Phospho-IRS-1 (Ser612) Sandwich ELISA Kit is a solid phase sandwich enzyme-linked immunosorbent assay (ELISA) that detects endogenous levels of IRS-1 when phosphorylated at Ser612. An IRS-1 Rabbit Antibody has been coated onto the microwells. After incubation with cell lysates, IRS-1 (phospho and nonphospho) is captured by the coated antibody. Following extensive washing, a Phospho-IRS-1 (Ser612) Mouse Detection Antibody is added to detect phosphorylation of Ser612 on the captured IRS-1 protein. Anti-mouse IgG, HRP-linked Antibody is then used to recognize the bound detection antibody. HRP substrate, TMB, is added to develop color. The magnitude of the absorbance for this developed color is proportional to the quantity of IRS-1 phosphorylated at Ser612.

Antibodies in kit are custom formulations specific to kit.

Specificity / Sensitivity

CST's PathScan® Phospho-IRS-1 (Ser612) Sandwich ELISA Kit #7332 detects endogenous levels of Phospho-IRS-1 when phosphorylated at Ser612. As shown in Figure 1, a significant induction of IRS-1 phosphorylation at Ser612 can be detected in hSkMC and CHO (IR/IRS-1) cells following treatment with insulin using the Phospho-IRS-1 (Ser612) Sandwich ELISA Kit #7332. The level of total IRS-1 (phospho and nonphospho) remains unchanged as shown by Western analysis and by PathScan® Total IRS-1 Sandwich ELISA Kit #7328 (Figure 1). This kit detects proteins from the indicated species, as determined through in-house testing, but may also detect homologous proteins from other species.

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, 73-77.

2.  Sun, X.J. et al. (1992) J. Biol. Chem. 267, 22662-22672.

3.  Myers Jr., M.G. et al. (1993) Endocrinology 132, 1421-1430.

4.  Wang, L.M. et al. (1993) Science 261, 1591-1594.

5.  Rui, L. et al. (1997) J. Clin. Invest. 107, 181-189.

6.  Gao, Z. et al. (2002) J. Biol. Chem. 277, 48115-48121.

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

8.  Ozes, O.N. et al. (2001) Proc. Natl. Acad. Sci. USA 98, 4640-4645.

9.  De Fea, K. and Ruth, R.A. (1997) Biochemistry 36, 12939-12947.

10.  Li, Y. et al. (2004) J. Biol. Chem. 279, 45304-45307.

Entrez-Gene Id 3667
Swiss-Prot Acc. P35568

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-IRS-1 (Ser612) Sandwich ELISA Kit