T cell receptor signaling controls Foxp3 expression via PI3K, Akt, and mTOR

作者：Stephan Sauer, Ludovica Bruno, Arnulf Hertweck, David K. Finlay, Marion Leleu, Mikhail Spivakov, Zachary A. Knight, Bradley S. Cobb, Doreen A. Cantrell, Eric O’Connor, Kevan M. Shokat, Amanda G. Fisher, Matthias Merkenschlager · 发表于：Proceedings of the National Academy of Sciences · 年份：2008 · DOI：10.1073/pnas.0800928105 · 被引用次数：850 · 研究领域：T-cell and B-cell Immunology、Immune Cell Function and Interaction、Immunotherapy and Immune Responses

Regulatory T (Treg) cells safeguard against autoimmunity and immune pathology. Because determinants of the Treg cell fate are not completely understood, we have delineated signaling events that control the de novo expression of Foxp3 in naive peripheral CD4 T cells and in thymocytes. We report that premature termination of TCR signaling and inibition of phosphatidyl inositol 3-kinase (PI3K) p110alpha, p110delta, protein kinase B (Akt), or mammalian target of rapamycin (mTOR) conferred Foxp3 expression and Treg-like gene expression profiles. Conversely, continued TCR signaling and constitutive PI3K/Akt/mTOR activity antagonised Foxp3 induction. At the chromatin level, di- and trimethylation of lysine 4 of histone H3 (H3K4me2 and -3) near the Foxp3 transcription start site (TSS) and within the 5' untranslated region (UTR) preceded active Foxp3 expression and, like Foxp3 inducibility, was lost upon continued TCR stimulation. These data demonstrate that the PI3K/Akt/mTOR signaling network regulates Foxp3 expression.