PCNA

From Wikipedia, the free encyclopedia

The assembled human DNA clamp, a trimer of the protein PCNA.
proliferating cell nuclear antigen
Identifiers
Symbol	PCNA
HUGO	8729
Entrez	5111
OMIM	176740
RefSeq	NM_002592
UniProt	P12004
Other data
Locus	Chr. 20 pter-p12

Proliferating Cell Nuclear Antigen, commonly known as PCNA, is a protein that acts as a processivity factor for DNA polymerase delta in eukaryotic cells.

Contents 1 Expression in the nucleus during DNA synthesis 2 Role in DNA repair 3 See also 4 External links 5 References 6 External links

[edit] Expression in the nucleus during DNA synthesis

PCNA was originally identified as an antigen that is expressed in the nuclei of cells during the DNA synthesis phase of the cell cycle ^[1]. Part of the protein was sequenced and that sequence was used to allow isolation of a cDNA clone ^[2]. PCNA helps hold DNA polymerase delta (Pol δ) to DNA. PCNA is clamped ^[3] to DNA through the action of replication factor C (RFC) ^[4]. Expression of PCNA is under the control of E2F transcription factor-containing complexes ^[5].

[edit] Role in DNA repair

Since DNA polymerase delta is involved in resynthesis of excised damaged DNA strands during DNA repair, PCNA is important for both DNA synthesis and DNA repair ^[6]. PCNA is also involved in the switch to DNA damage bypass translation synthesis.

[edit] See also

• Transcription

[edit] External links

• PCNA type 1 and type 2 antibody - look in the mitotic section of the Rheumatic disease

• Model of PCNA ring clamped to DNA from the Advanced Light Source (accessed June 15, 2006)^[3].
• Movie showing a model of clamp loading of PCNA onto DNA (accessed June 15, 2006) ^[7].

[edit] References

[edit] External links

• MeSH PCNA