Ornithine decarboxylase antizyme
In molecular biology, Ornithine decarboxylase antizyme is an ornithine decarboxylase inhibitor. It binds to, and destabilises, ornithine decarboxylase, a key enzyme in polyamine synthesis. ODC is then rapidly degraded. It was first characterized in 1981. The expression of ODC-AZ requires programmed, ribosomal frameshifting which is modulated according to the cellular concentration of polyamines. High levels of polyamines induce a +1 ribosomal frameshift in the translation of mRNA for the antizyme leading to the expression of a full-length protein. At least two forms of ODC-AZ exist in mammals and the protein has been found in Drosophila as well as in Saccharomyces yeast.
Human genes encoding Ornithine decarboxylase antizymes are OAZ1, OAZ2, and OAZ3.