Repairs oxidative DNA damages, seems also to act as a redox factor (PubMed:7512729). Is multifunctional and may be involved both in DNA repair and in the regulation of transcription (PubMed:7512729). Exhibits apurinic/apyrimidinic (AP) endonuclease activity (PubMed:25569774, PubMed:21781197, PubMed:25228464). Catalyzes the conversion of 3'-phosphor-alpha,beta-unsaturated aldehyde (3'-PUA) to 3'-OH (PubMed:25228464). May be involved in base excision repair in chloroplasts (PubMed:19372224). According to a report, has a significant in vitro 3'-phosphatase activity (PubMed:25228464). According to another report, has no in vitro 3'-phosphatase activity (PubMed:25569774). Has a strong non-specific affinity to DNA (PubMed:25228464). Exonucleolytic cleavage in the 3'- to 5'-direction to yield nucleoside 5'-phosphates. Probably binds two magnesium or manganese ions per subunit. A number of isoforms are produced. According to EST sequences. Expressed in the siliques, flowers, and stems (PubMed:7512729). A high level expression is seen in the leaves (PubMed:7512729). Expressed in both vegetative and reproductive organs (PubMed:25228464). No visible phenotype (PubMed:19372224, PubMed:19172180, PubMed:21781197, PubMed:25569774). Loss of chloroplastic glycosylase-lyase/endonuclease activity (PubMed:19372224). Hypersensitivity to 5-fluorouracil (PubMed:21781197). Ape1l arp double mutants have no visible phenotype (PubMed:19172180). Ape2 arp double mutants have no visible phenotype (PubMed:19172180). Belongs to the DNA repair enzymes AP/ExoA family.