Reactome: A Curated Pathway Database

Regulation of ornithine decarboxylase (ODC)

Stable Identifier
R-HSA-350562
Type
Pathway
Species
Homo sapiens
Compartment
Locations in the PathwayBrowser
Summation

Polyamines increase the production of antizyme (AZ). The carboxy-terminal half of antizyme interacts with ODC, generating an inactive AZ:ODC heterodimer complex. A carboxy-terminal domain of ODC is exposed only within the heterodimer, and is the target for subsequent degradation. A domain within the amino-terminal portion of antizyme provides a function needed for efficient degradation of ODC by the proteasome.
The proteasome cycle starts with the processing of AZ:ODC, sequestering ODC and then degrading it to peptides but releasing AZ. AZ participates in additional rounds of binding and degradation. Antizyme-mediated inhibition and destruction of ODC reduces synthesis of polyamines. Additionally, antizyme also inhibits polyamine transport into the cell. Antizyme production is reduced, completing the regulatory circuit (Coffino, 2001).
The following illustration is adapted from a minireview by Pegg, 2006; J. Biol. Chem., Vol. 281, Issue 21, 14529-14532.

Literature References
PubMed ID Title Journal Year
Participants
Participant Of
Orthologous Events