Participates in various redox reactions through the reversible oxidation of its active center dithiol to a disulfide and catalyzes dithiol-disulfide exchange reactions. As a reducing substrate of peroxiredoxin 1, thioredoxin 2 is preferred over thioredoxin 1. Required for female meiosis and early embryonic development. Ovary specific. Expressed present in the nurse cells from stage 9 of ovary development and is transported into the oocyte. Expressed throughout oogenesis. Expressed both maternally and zygotically. The TrxT gene, which encodes an testis specific thioredoxin, is adjacent to the dhd gene and shares some regulatory region with it. Belongs to the thioredoxin family.