May function as a general inhibitor of the histone deacetylase HDAC1. Binding to the pocket region of RB1 may displace HDAC1 from RB1/E2F complexes, leading to activation of E2F target genes and cell cycle progression. Conversely, displacement of HDAC1 from SP1 bound to the CDKN1A promoter leads to increased expression of this CDK inhibitor and blocks cell cycle progression. Also antagonizes PAWR mediated induction of aberrant amyloid peptide production in Alzheimer disease (presenile and senile dementia), although the molecular basis for this phenomenon has not been described to date. Binds PAWR, POLR2J, RB1/RB, RBL1/P107, RBL2/P130, and SP1. May also bind MAPT. Ubiquitously expressed. Expressed at high levels in brain, heart, kidney, placenta and thymus. Hyperphosphorylated during the G1/S phase transition. Belongs to the AATF family.