Transcription of the RBL2 gene is directly stimulated by FOXO family transcription factors FOXO1, FOXO3 and FOXO4 (Kops et al. 2002, Chen et al. 2006). Direct transcriptional stimulation by human FOXO4 was demonstrated for human RBL2 gene (Kops et al. 2002), and by human FOXO1 and FOXO3 for mouse Rbl2 gene (Chen et al. 2006). The retinoblastoma family member RBL2 is needed for the establishment and maintenance of quiescent, G0, state.