Participates in various redox reactions through the reversible oxidation of its active center dithiol to a disulfide and catalyzes dithiol-disulfide exchange reactions (By similarity). As part of the translocon PTEX complex, plays a role in the export of parasite proteins into the host erythrocyte (PubMed:25043043). The translocon PTEX complex is a multi-protein machinery resident in the parasite parasitophorous vacuolar membrane, responsible for protein secretion into host cells (PubMed:23869529, PubMed:25043043). May contribute to the unfolding of proteins containing the PEXEL localization motif before their passage through the translocon or regulate the PTEX complex function (PubMed:25043043). Monomer (By similarity). Component of the translocon PTEX complex composed of HSP101, EXP2, PTEX150, PTEX88 and TRX2 (PubMed:23869529). The disulfide bond between Cys-82 and Cys-85 acts as a redox-active center and is reduced by thioredoxin reductase TRXR. Mice of infection with knockout parasites have reduced blood parasitemia due to a slower growth at the ring and schizont stages (PubMed:23869529). Parasite burden in vessels of lung and adipose tissue is reduced (PubMed:25820521). Also, the development of experimental cerebral malaria is delayed (PubMed:23869529, PubMed:25820521). In infected host erythrocytes, surface expression of parasite antigens is reduced (PubMed:25043043). Belongs to the thioredoxin family.