Anti-IRS-1 (Insulin Receptor Substrate-1)

Following tyrosine phosphorylation, the insulin receptor substrate 1 and 2 (IRS-1 and IRS-2) can form a protein scaffolding for the assembly of a host of Src homology 2 (SH2) domain-containing proteins (1). IRS-1 tyrosine phosphorylation can occur through the activity of several cytokine and growth factor receptors such as interleukin (IL)-4, IL-9, interferon-gamma, in addition to the insulin and insulin-like growth factor 1 receptors (2). The scaffolding provided by IRS-1 and IRS-2 is necessary for insulin signal transduction across the cell membrane. IRS-1 tyrosine phosphorylation, and thus formation of the IRS scaffolding is inhibited by tumor necrosis factor (TNF), and this inhibition can itself be blocked by rapamycin, an inhibitor of the mammalian target of rapamycin (TOR) (3,4). TNF activity could also be blocked by inhibition of the Akt kinase and the PTEN tumor suppressor, suggesting that TNF impairs insulin signaling through IRS- 1 by activation of the TOR signaling pathway (3). Applications: Suitable for use in Western Blot and Immunocytochemistry. Other applications not tested. Recommended Dilution: Western Blot: 1-2ug/ml, Immunocytochemistry: 2ug/ml, IOptimal dilutions to be determined by the researcher. Positive Control: PC-3 cell lysate (Western Blot), Storage and Stability: May be stored at 4°C for short-term only. Aliquot to avoid repeated freezing and thawing. Store at -20°C. Aliquots are stable for 12 months after receipt. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.