Figure 2
From: E2F1 activation is responsible for pituitary adenomas induced by HMGA2 gene overexpression
Schematic model of E2F1 activation by HMGA2. Following HMGA2 overexpression, transcription through E2F1 sites switches from repression to activation through four steps: 1- HMGA2 binds to pRB, which is complexed with E2F1 and HDAC1 to form the active repression; 2- the interaction between HMGA2 and pRB displaces HDAC1; 3- in the absence of HDAC1, the histone acetylase enzymes are recruited and, by acetylating histones, relieve transcriptional repression; 4- histone acetylases also acetylate E2F1 causing the stabilization of its "free" active form.