Module 4: Figure FOXO control mechanisms
Control of forkhead box O (FOXO) proteins by the PtdIns 3-kinase signalling cassette.
The forkhead box O (FOXO) family are typical shuttle nuclear transcription factors that bind to a specific promoter sequence to activate the transcription of genes such as p27, p130, Bim and manganese superoxide dismutase (MnSOD). Like many other transcription factors, FOXO can bind p300, thereby acetylating histone to make DNA more accessible to transcription. The transcriptional activity of FOXO is inhibited by phosphorylation through the PtdIns 3-kinase signalling cassette, resulting in export from the nucleus into the cytoplasm. (See the text for details of the signalling pathway.)