| Structural highlights
Function
PCNA_HUMAN Auxiliary protein of DNA polymerase delta and is involved in the control of eukaryotic DNA replication by increasing the polymerase's processibility during elongation of the leading strand. Induces a robust stimulatory effect on the 3'-5' exonuclease and 3'-phosphodiesterase, but not apurinic-apyrimidinic (AP) endonuclease, APEX2 activities. Has to be loaded onto DNA in order to be able to stimulate APEX2. Plays a key role in DNA damage response (DDR) by being conveniently positioned at the replication fork to coordinate DNA replication with DNA repair and DNA damage tolerance pathways. Acts as a loading platform to recruit DDR proteins that allow completion of DNA replication after DNA damage and promote postreplication repair: Monoubiquitinated PCNA leads to recruitment of translesion (TLS) polymerases, while 'Lys-63'-linked polyubiquitination of PCNA is involved in error-free pathway and employs recombination mechanisms to synthesize across the lesion.[1] [2]
Publication Abstract from PubMed
Structurally complex genomic regions, such as centromeres, are inherently difficult to duplicate. The mechanism behind centromere inheritance is not well understood, and one of the key questions relates to the reassembly of centromeric chromatin following DNA replication. Here, we define ERCC6L2 as a key regulator of this process. ERCC6L2 accumulates at centromeres and promotes deposition of core centromeric factors. Interestingly, ERCC6L2(-/-) cells show unrestrained replication of centromeric DNA, likely caused by the erosion of centromeric chromatin. Beyond centromeres, ERCC6L2 facilitates replication at genomic repeats and non-canonical DNA structures. Notably, ERCC6L2 interacts with the DNA-clamp PCNA through an atypical peptide, presented here in a co-crystal structure. Finally, ERCC6L2 also restricts DNA end resection, acting independently of the 53BP1-REV7-Shieldin complex. We propose a mechanistic model, which reconciles seemingly distinct functions of ERCC6L2 in DNA repair and DNA replication. These findings provide a molecular context for studies linking ERCC6L2 to human disease.
ERCC6L2 mitigates replication stress and promotes centromere stability.,Carnie CJ, Armstrong L, Sebesta M, Ariza A, Wang X, Graham E, Zhu K, Ahel D Cell Rep. 2023 Apr 3;42(4):112329. doi: 10.1016/j.celrep.2023.112329. PMID:37014751[3]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Burkovics P, Hajdu I, Szukacsov V, Unk I, Haracska L. Role of PCNA-dependent stimulation of 3'-phosphodiesterase and 3'-5' exonuclease activities of human Ape2 in repair of oxidative DNA damage. Nucleic Acids Res. 2009 Jul;37(13):4247-55. doi: 10.1093/nar/gkp357. Epub 2009, May 13. PMID:19443450 doi:10.1093/nar/gkp357
- ↑ Motegi A, Liaw HJ, Lee KY, Roest HP, Maas A, Wu X, Moinova H, Markowitz SD, Ding H, Hoeijmakers JH, Myung K. Polyubiquitination of proliferating cell nuclear antigen by HLTF and SHPRH prevents genomic instability from stalled replication forks. Proc Natl Acad Sci U S A. 2008 Aug 26;105(34):12411-6. Epub 2008 Aug 21. PMID:18719106 doi:0805685105
- ↑ Carnie CJ, Armstrong L, Sebesta M, Ariza A, Wang X, Graham E, Zhu K, Ahel D. ERCC6L2 mitigates replication stress and promotes centromere stability. Cell Rep. 2023 Apr 3;42(4):112329. PMID:37014751 doi:10.1016/j.celrep.2023.112329
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