IndraLab

Statements


IRS1 phosphorylated on S639 is inactive. 3 / 3
3 |

"In this report, we identified insulin receptor substrate 1 (IRS-1), a critical mediator of the insulin/insulin-like growth factor 1 signaling, as a proteolytic target of the CUL7 E3 ligase in a manner that depends on mammalian target of rapamycin and the p70 S6 kinase activities.Elimination of phosphorylation at S307/S312/S527/S636/S639 renders V5-IRS-1 partially resistant to degradation by Fbw8"

"Nevertheless, s6k1-deficient mice remain sensitive to insulin owing to the apparent loss of a negative feedback loop from s6k1 to insulin receptor substrate 1 (irs1), which blunts s307 and s636/s639 phosphorylation; thus under conditions of nutrient satiation s6k1 negatively regulatesinsulin."

"Mtor induced the serine phosphorylation of irs-1 (ser-636/639), and such phosphorylation was inhibited by rapamycin. These results suggest that tnf impairs insulin signaling through irs-1 by activation of a pi 3-kinase/akt/mtor pathway, which is antagonized by pten"