title: The 9-1-1 checkpoint clamp physically interacts with polzeta and is partially required for spontaneous polzeta-dependent mutagenesis in Saccharomyces cerevisiae.
abstract: The use of translesion synthesis (TLS) polymerases to bypass DNA lesions during replication constitutes an important mechanism to restart blocked/stalled DNA replication forks. Because TLS polymerases generally have low fidelity on undamaged DNA, the cell must regulate the interaction of TLS polymerases with damaged versus undamaged DNA to maintain genome integrity. The Saccharomyces cerevisiae checkpoint proteins Ddc1, Rad17, and Mec3 form a clamp-like structure (the 9-1-1 clamp) that has physical similarity to the homotrimeric sliding clamp proliferating cell nuclear antigen, which interacts with and promotes the processivity of the replicative DNA polymerases. In this work, we demonstrate both an in vivo and in vitro physical interaction between the Mec3 and Ddc1 subunits of the 9-1-1 clamp and the Rev7 subunit of the Polzeta TLS polymerase. In addition, we demonstrate that loss of Mec3, Ddc1, or Rad17 results in a decrease in Polzeta-dependent spontaneous mutagenesis. These results suggest that, in addition to its checkpoint signaling role, the 9-1-1 clamp may physically regulate Polzeta-dependent mutagenesis by controlling the access of Polzeta to damaged DNA.
authors.affiliation: Dipartimento di Scienze Biomolecolari e Biotecnologie, Università degli Studi di Milano, Milano, Italy 20133.
authors.forename: Simone
authors.initials: S
authors.lastname: Sabbioneda
authors.forename: Brenda K
authors.initials: BK
authors.lastname: Minesinger
authors.forename: Michele
authors.initials: M
authors.lastname: Giannattasio
authors.forename: Paolo
authors.initials: P
authors.lastname: Plevani
authors.forename: Marco
authors.initials: M
authors.lastname: Muzi-Falconi
authors.forename: Sue
authors.initials: S
authors.lastname: Jinks-Robertson
mesh_terms: D001483:Base Sequence; D018797:Cell Cycle Proteins / Q000737:chemistry / Q000378:metabolism*; D002875:Chromosomes / Q000378:metabolism / Q000648:ultrastructure; D004247:DNA / Q000737:chemistry; D004249:DNA Damage; D004260:DNA Repair; D004261:DNA Replication; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000378:metabolism*; D004259:DNA-Directed DNA Polymerase / Q000737:chemistry* / Q000378:metabolism; D019281:Dimerization; D016368:Frameshift Mutation; D015966:Gene Expression Regulation, Fungal; D016681:Genome, Fungal; D005982:Glutathione Transferase / Q000378:metabolism; D047468:Immunoprecipitation; D047908:Intracellular Signaling Peptides and Proteins / Q000737:chemistry; D008969:Molecular Sequence Data; D016296:Mutagenesis; D009154:Mutation; D009687:Nuclear Proteins / Q000737:chemistry / Q000378:metabolism*; D010750:Phosphoproteins / Q000737:chemistry / Q000378:metabolism*; D010957:Plasmids / Q000378:metabolism; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D016196:S Phase; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry* / Q000378:metabolism*; D020798:Two-Hybrid System Techniques; D014466:Ultraviolet Rays
chemical_list: D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; C440013:Ddc1 protein, S cerevisiae; D047908:Intracellular Signaling Peptides and Proteins; C099938:MEC3 protein, S cerevisiae; D009687:Nuclear Proteins; D010750:Phosphoproteins; D018809:Proliferating Cell Nuclear Antigen; C501395:RAD17 protein, S cerevisiae; C088385:RAD24 protein, S cerevisiae; C092219:REV7 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D004247:DNA; D005982:Glutathione Transferase; C425929:DNA polymerase zeta; D004259:DNA-Directed DNA Polymerase