Antizyme inhibitor protein that positively regulates ornithine decarboxylase (ODC) activity and polyamine uptake by counteracting the negative effect of antizymes OAZ1, OAZ2 and OAZ3 on ODC1 activity (PubMed:17900240). Inhibits antizyme-dependent ODC1 degradation by binding to antizymes. Releases ODC1 from its inactive complex with antizymes, leading to formation of the catalytically active ODC1. Participates in the morphological integrity of the trans-Golgi network (TGN) and functions as a regulator of intracellular secretory vesicle trafficking (PubMed:20188728).
