Human ELG1 regulates the level of ubiquitinated proliferating cell nuclear antigen (PCNA) through Its interactions with PCNA and USP1.
The level of monoubiquitinated proliferating cell nuclear antigen (PCNA) is closely linked with DNA damage bypass to protect cells from a high level of mutagenesis. However, it remains unclear how the level of monoubiquitinated PCNA is regulated. Here, we demonstrate that human ELG1 protein, which comprises an alternative replication factor C (RFC) complex and plays an important role in preserving genomic stability, as an interacting partner for the USP1 (ubiquitin-specific protease 1)-UAF1 (USP1-associated factor 1) complex, a deubiquitinating enzyme complex for PCNA and FANCD2. ELG1 protein interacts with PCNAs that are localized at stalled replication forks. ELG1 knockdown specifically resulted in an increase in the level of PCNA monoubiquitination without affecting the level of FANCD2 ubiquitination. It is a novel function of ELG1 distinct from its role as an alternative RFC complex because knockdowns of any other RFC subunits or other alternative RFCs did not affect PCNA monoubiquitination. Lastly, we identified a highly conserved N-terminal domain in ELG1 that was responsible for the USP1-UAF1 interaction as well as the activity to down-regulate PCNA monoubiquitination. Taken together, ELG1 specifically directs USP1-UAF1 complex for PCNA deubiquitination.
Genome Instability Section, Genetics and Molecular Biology Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland 20892, USA.
Kyoo-Young
KY
Lee
Kailin
K
Yang
Martin A
MA
Cohn
Nilabja
N
Sikdar
Alan D
AD
D'Andrea
Kyungjae
K
Myung
D000074183:ATPases Associated with Diverse Cellular Activities; D000251:Adenosine Triphosphatases; D029681:Arabidopsis Proteins; D002478:Cells, Cultured; D002843:Chromatin / Q000502:physiology; D004249:DNA Damage; D004261:DNA Replication; D004268:DNA-Binding Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D010450:Endopeptidases / Q000235:genetics / Q000378:metabolism*; D052236:Fanconi Anemia Complementation Group D2 Protein / Q000235:genetics / Q000378:metabolism; D006801:Humans; D015151:Immunoblotting; D047468:Immunoprecipitation; D007668:Kidney / Q000166:cytology / Q000378:metabolism; D009154:Mutation / Q000235:genetics; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D018809:Proliferating Cell Nuclear Antigen / Q000235:genetics / Q000378:metabolism*; D011499:Protein Processing, Post-Translational; D034741:RNA, Small Interfering / Q000494:pharmacology; D011995:Recombination, Genetic; D014169:Transformation, Bacterial; D025801:Ubiquitin / Q000378:metabolism*; D064570:Ubiquitin-Specific Proteases; D054875:Ubiquitination
D000074183:ATPases Associated with Diverse Cellular Activities; D000251:Adenosine Triphosphatases; D029681:Arabidopsis Proteins; D002843:Chromatin; D004268:DNA-Binding Proteins; D010450:Endopeptidases; D052236:Fanconi Anemia Complementation Group D2 Protein; D009687:Nuclear Proteins; D018809:Proliferating Cell Nuclear Antigen; D034741:RNA, Small Interfering; D025801:Ubiquitin; D064570:Ubiquitin-Specific Proteases; C546328:ATAD5 protein, human; C499905:FANCD2 protein, human; C526165:WDR48 protein, human; C579228:USP1 protein, human