Special regulatory T-cell review: FOXP3 biochemistry in regulatory T cells--how diverse signals regulate suppression.

FOXP3 is an acetylated and phosphorylated protein active in human regulatory T cells and forms oligomers which then associate with an even larger molecular complex. FOXP3 actively regulates transcription by recruiting enzymatic co-repressors and/or co-activators. FOXP3 complex ensembles are dynamically regulated by physiological stimuli such as T-cell receptor, IL-2 and proinflammation cytokine signals. Understanding the post-translational modifications of FOXP3 regulated by diverse signals and the biochemistry and structural chemistry of enzymatic proteins in the FOXP3 complex is critical for therapeutically modulating regulatory T cell function.