Multifunctional protein working as a cell cycle progression factor as well as a cell survival factor. Required for the progression from the G1 to the S phase. Anti-apoptotic protein which functions as a caspase-3 inhibitor. Has no phosphatase 2A (PP2A) inhibitor activity. Exhibits histone chaperone properties, stimulating core histones to assemble into a nucleosome (By similarity). Monomer. Interacts with histones H3 and H4 (By similarity). Accumulates in the nuclei at the S phase. Histone binding is mediated by the concave surface of the LRR region. Some glutamate residues are glycylated by TTLL8. This modification occurs exclusively on glutamate residues and results in a glycine chain on the gamma-carboxyl group (By similarity). Belongs to the ANP32 family.