Skip to main content
. 2008 Dec 19;283(51):35375–35382. doi: 10.1074/jbc.M806480200

FIGURE 4.

FIGURE 4.

Phosphorylation of Ser-270 regulates ability of S6K to interactive with IRS-1 and phosphorylate other phosphorylation sites on IRS-1. A, HEK293 cells were transfected with either HA-tagged wild-type IRS-1, or IRS-1 S270A mutant. After overnight serum-starvation, transfected cells were treated without or with TNF-α (10 ng/ml, 30 min) to induce S6K activation. After immunoprecipitation (IP) with anti-HA antibody, IRS-1/S6K association was determined by immunoblotting with S6K antibody. Phosphorylation of HA-IRS-1 wild-type and S270A mutant was determined by immunoblotting with phosphospecific antibodies against pSer-270, pSer-307, pSer-636, and pSer-1101 in the human IRS-1. B, quantification of immunoblots. Each bar represents the mean ± S.E. of three independent experiments. *, p < 0.05 and **, p < 0.001.