Implicated in a number of cellular processes, including proliferation, differentiation, caspase-dependent and caspase-independent apoptosis, suppression of transformation (tumor suppressor), inhibition of protein phosphatase 2A, regulation of mRNA trafficking and stability, and inhibition of acetyltransferases as part of the INHAT (inhibitor of histone acetyltransferases) complex. Phosphorylated on serine residues. Belongs to the ANP32 family.