Exhibits apurinic/apyrimidinic (AP) endonuclease activity in vitro. By contrast, another report show that APE2 has no biochemical activity. Unable to catalyze the conversion of 3'-phosphor-alpha,beta-unsaturated aldehyde (3'-PUA) to 3'-OH. Has no in vitro 3'-phosphatase activity. Redundant with APE1L and at least one functional allele is required for seed viability. Has a strong non-specific affinity to DNA