FOXO1 directly represses transcription of the SREBF1 (SREBP1) gene, encoding Sterol regulatory element-binding protein 1, a transcriptional activator required for lipid homeostasis (Deng et al. 2012). FOXO1 binding interferes with recruitment of SREBF1 transcriptional activator NR1H3 (LXRA) to the SREBF1 promoter (Liu et al. 2010). CRY1, a transcriptional target of SREBF1, downregulates FOXO1 protein levels by promoting MDM2-mediated polyubiquitination and degradation of FOXO1 (Jang et al. 2016).