Replication protein A and proliferating cell nuclear antigen coordinate DNA polymerase selection in 8-oxo-guanine repair.
The adenine misincorporated by replicative DNA polymerases (pols) opposite 7,8-dihydro-8-oxoguanine (8-oxo-G) is removed by a specific glycosylase, leaving the lesion on the DNA. Subsequent incorporation of C opposite 8-oxo-G on the resulting 1-nt gapped DNA is essential for the removal of the 8-oxo-G to prevent G-C to T-A transversion mutations. By using model DNA templates, purified DNA pols beta and lambda and knockout cell extracts, we show here that the auxiliary proteins replication protein A and proliferating cell nuclear antigen act as molecular switches to activate the DNA pol lambda- dependent highly efficient and faithful repair of A:8-oxo-G mismatches in human cells and to repress DNA pol beta activity. By using an immortalized human fibroblast cell line that has the potential to induce cancer in mice, we show that the development of a tumoral phenotype in these cells correlated with a differential expression of DNA pols lambda and beta.
Maga
Giovanni
G
Institute of Molecular Genetics, Consiglio Nazionale delle Ricerche, Via Abbiategrasso 207, I-27100 Pavia, Italy. maga@igm.cnr.it
Crespan
Emmanuele
E
Wimmer
Ursula
U
van Loon
Barbara
B
Amoroso
Alessandra
A
Mondello
Chiara
C
Belgiovine
Cristina
C
Ferrari
Elena
E
Locatelli
Giada
G
Villani
Giuseppe
G
Hübscher
Ulrich
U
D000818:Animals; D002461:Cell Line, Transformed; D002471:Cell Transformation, Neoplastic / Q000235:genetics / Q000378:metabolism; D002474:Cell-Free System / Q000378:metabolism; D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000235:genetics / Q000378:metabolism; D004247:DNA / Q000235:genetics / Q000378:metabolism; D045647:DNA Glycosylases / Q000235:genetics / Q000378:metabolism; D019951:DNA Polymerase beta / Q000235:genetics / Q000378:metabolism*; D004260:DNA Repair / Q000235:genetics; D004261:DNA Replication / Q000235:genetics; D006147:Guanine / Q000031:analogs & derivatives* / Q000378:metabolism; D006801:Humans; D051379:Mice; D009154:Mutation; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism*; D016271:Proto-Oncogene Proteins c-myc / Q000235:genetics / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D051716:Replication Protein A / Q000235:genetics / Q000378:metabolism*; D025803:Tumor Suppressor Protein p14ARF / Q000235:genetics / Q000378:metabolism; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism
C453560:7,8-dihydro-8-oxoguanine; D019941:Cyclin-Dependent Kinase Inhibitor p16; C489427:MYC protein, human; D018809:Proliferating Cell Nuclear Antigen; D016271:Proto-Oncogene Proteins c-myc; D017382:Reactive Oxygen Species; D051716:Replication Protein A; C495901:TP53 protein, human; D025803:Tumor Suppressor Protein p14ARF; D016159:Tumor Suppressor Protein p53; D006147:Guanine; D004247:DNA; C415367:DNA polymerase beta2; D019951:DNA Polymerase beta; D045647:DNA Glycosylases; C061738:mutY adenine glycosylase