Ornithine Decarboxylase Antizyme 3 (OAZ3)

Ornithine decarboxylase catalyzes the conversion of ornithine to putrescine in the first and apparently rate-limiting step in polyamine biosynthesis. The ornithine decarboxylase antizymes play a role in the regulation of polyamine synthesis by binding to and inhibiting ornithine decarboxylase.

Antizyme expression is auto-regulated by polyamine-enhanced translational frameshifting. In contrast to antizymes 1 and 2, which are widely expressed throughout the body, the expression of this gene product (antizyme 3) is restricted to testis germ cells, and thus it is a possible candidate for heritable forms of human male infertility. Alternatively spliced transcript variants encoding different isoforms have been found for this gene.