PCNA

PCNA is involved in origin licensing is chromatin licensing and DNA replication factor 1 (CDT1) and, therefore, activity of this protein must be strictly controlled.

Four recent articles have demonstrated that proliferating cell nuclear antigen (PCNA), an essential sliding clamp used in replication and DNA repair, has a crucial role in this process by mediating the proteasomal degradation of CDT1.

To prevent duplication or loss of genomic regions during DNA replication, it is essential that the entire genome is copied precisely once every S phase. Cells achieve this by mutually exclusive regulation of origin firing and licensing.

References

 Green CM. One ring to rule them all? Another cellular responsibility for PCNA. Trends Mol Med. 2006 Oct;12(10):455-8. PMID: 16931160