Members of this family have two highly conserved cysteine residues within the DxxCxxC motif at the N-terminal. This motif is conserved in the thiol-disulfide oxidoreductase family [1]. This family includes At5g50100 (also known as DCC1) from Arabidopsis thaliana, a thioredoxin that modulates ROS homeostasis resulting in de novo shoot initiation and may be involved in the improvement of the capacity of plant regeneration [1]. Uncharacterised proteins from bacteria are also included in this family.

1: Thioredoxin-Mediated ROS Homeostasis Explains Natural Variation in Plant Regeneration. Zhang H, Zhang TT, Liu H, Shi Y, Wang M, Bie XM, Li XG, Zhang XS; Plant Physiol. 2018;176:2231-2250. PMID:28724620