title: Ribonucleotide incorporation by human DNA polymerase η impacts translesion synthesis and RNase H2 activity.
abstract: Ribonucleotides (rNs) incorporated in the genome by DNA polymerases (Pols) are removed by RNase H2. Cytidine and guanosine preferentially accumulate over the other rNs. Here we show that human Pol η can incorporate cytidine monophosphate (rCMP) opposite guanine, 8-oxo-7,8-dihydroguanine, 8-methyl-2΄-deoxyguanosine and a cisplatin intrastrand guanine crosslink (cis-PtGG), while it cannot bypass a 3-methylcytidine or an abasic site with rNs as substrates. Pol η is also capable of synthesizing polyribonucleotide chains, and its activity is enhanced by its auxiliary factor DNA Pol δ interacting protein 2 (PolDIP2). Human RNase H2 removes cytidine and guanosine less efficiently than the other rNs and incorporation of rCMP opposite DNA lesions further reduces the efficiency of RNase H2. Experiments with XP-V cell extracts indicate Pol η as the major basis of rCMP incorporation opposite cis-PtGG. These results suggest that translesion synthesis by Pol η can contribute to the accumulation of rCMP in the genome, particularly opposite modified guanines.
authors.affiliation: DNA Enzymology & Molecular Virology and Cell Nucleus & DNA replication Units, Institute of Molecular Genetics IGM-CNR, via Abbiategrasso 207, I-27100 Pavia, Italy.
authors.forename: Elisa
authors.initials: E
authors.lastname: Mentegari
authors.affiliation: DNA Enzymology & Molecular Virology and Cell Nucleus & DNA replication Units, Institute of Molecular Genetics IGM-CNR, via Abbiategrasso 207, I-27100 Pavia, Italy.
authors.forename: Emmanuele
authors.initials: E
authors.lastname: Crespan
authors.affiliation: DNA Enzymology & Molecular Virology and Cell Nucleus & DNA replication Units, Institute of Molecular Genetics IGM-CNR, via Abbiategrasso 207, I-27100 Pavia, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Bavagnoli
authors.affiliation: DNA Enzymology & Molecular Virology and Cell Nucleus & DNA replication Units, Institute of Molecular Genetics IGM-CNR, via Abbiategrasso 207, I-27100 Pavia, Italy.
authors.forename: Miroslava
authors.initials: M
authors.lastname: Kissova
authors.affiliation: DNA Enzymology & Molecular Virology and Cell Nucleus & DNA replication Units, Institute of Molecular Genetics IGM-CNR, via Abbiategrasso 207, I-27100 Pavia, Italy.
authors.forename: Federica
authors.initials: F
authors.lastname: Bertoletti
authors.affiliation: DNA Enzymology & Molecular Virology and Cell Nucleus & DNA replication Units, Institute of Molecular Genetics IGM-CNR, via Abbiategrasso 207, I-27100 Pavia, Italy.
authors.forename: Simone
authors.initials: S
authors.lastname: Sabbioneda
authors.affiliation: Department of Molecular Mechanisms of Disease, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland.
authors.forename: Ralph
authors.initials: R
authors.lastname: Imhof
authors.affiliation: Department of Health Sciences and Technology, ETH Zurich, Schmelzbergstrasse 9, CH-8092 Zürich, Switzerland.
authors.forename: Shana J
authors.initials: SJ
authors.lastname: Sturla
authors.affiliation: Department of Health Sciences and Technology, ETH Zurich, Schmelzbergstrasse 9, CH-8092 Zürich, Switzerland.
authors.forename: Arman
authors.initials: A
authors.lastname: Nilforoushan
authors.affiliation: Department of Molecular Mechanisms of Disease, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Hübscher
authors.affiliation: Department of Molecular Mechanisms of Disease, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland.
authors.forename: Barbara
authors.initials: B
authors.lastname: van Loon
authors.affiliation: DNA Enzymology & Molecular Virology and Cell Nucleus & DNA replication Units, Institute of Molecular Genetics IGM-CNR, via Abbiategrasso 207, I-27100 Pavia, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Maga
mesh_terms: D002460:Cell Line; D003568:Cytidine Monophosphate / Q000378:metabolism; D004247:DNA / Q000096:biosynthesis; D004249:DNA Damage; D004260:DNA Repair; D004259:DNA-Directed DNA Polymerase / Q000378:metabolism*; D006147:Guanine / Q000031:analogs & derivatives / Q000378:metabolism; D006801:Humans; D012313:RNA / Q000096:biosynthesis; D016914:Ribonuclease H / Q000378:metabolism*; D012265:Ribonucleotides / Q000378:metabolism*; D014983:Xeroderma Pigmentosum / Q000235:genetics; D000099270:Y-Family DNA Polymerases
chemical_list: D003568:Cytidine Monophosphate; D004247:DNA; D004259:DNA-Directed DNA Polymerase; D006147:Guanine; D012313:RNA; D016914:Ribonuclease H; D012265:Ribonucleotides; C024829:8-hydroxyguanine; C112338:Rad30 protein; D000099270:Y-Family DNA Polymerases; C091139:ribonuclease HII