title: [Interaction of replication protein A and flap endonuclease 1 with DNA duplexes containing a nick or flap].
abstract: Nicks and flaps are intermediates in various processes of DNA metabolism, including replication and repair. Photoaffinity modification was employed in studying the interaction of the replication protein A (RPA) and flap endonuclease 1 (FEN-1) with DNA duplexes similar to structures arising during long-patch base excision repair. The proteins were also tested for effect on DNA polymerase beta (Pol beta) interaction with DNA. Using Pol beta, a photoreactive dTTP analog was added to the 3' end of an oligonucleotide flanking a nick or a flap in DNA intermediates. The character and intensity of protein labeling depended on the type of intermediates and on the presence of the phosphate or tetrahydrofuran at the 5' end of a nick or a flap. Photoaffinity labeling of Pol beta substantially (up to three times) increased in the presence of RPA or FEN-1. Various DNA substrates were used to study the effects of RPA and FEN-1 on Pol beta-mediated DNA synthesis with displacement of a downstream primer. In contrast to FEN-1, RPA had no effect on DNA repair synthesis by Pol beta during long-patch base excision repair.
authors.affiliation: Novosibirsk Institute of Bioorganic Chemistry, Siberian Division, Russian Academy of Sciences, Novosibirsk, 630090 Russia.
authors.forename: D Iu
authors.initials: DIu
authors.lastname: Khlimankov
authors.forename: N I
authors.initials: NI
authors.lastname: Rechkunova
authors.forename: S N
authors.initials: SN
authors.lastname: Khodyreva
authors.forename: I O
authors.initials: IO
authors.lastname: Petruseva
authors.forename: Zh K
authors.initials: ZhK
authors.lastname: Nazarkina
authors.forename: E A
authors.initials: EA
authors.lastname: Belousova
authors.forename: O I
authors.initials: OI
authors.lastname: Lavrik
mesh_terms: D019951:DNA Polymerase beta / Q000378:metabolism; D004260:DNA Repair / Q000502:physiology; D004277:DNA, Single-Stranded / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D004706:Endodeoxyribonucleases / Q000235:genetics / Q000378:metabolism*; D045585:Flap Endonucleases; D009692:Nucleic Acid Heteroduplexes / Q000378:metabolism*; D009841:Oligonucleotides / Q000737:chemistry; D019920:Photoaffinity Labels / Q000737:chemistry; D051716:Replication Protein A; D013942:Thymine Nucleotides / Q000737:chemistry
chemical_list: D004277:DNA, Single-Stranded; D004268:DNA-Binding Proteins; D009692:Nucleic Acid Heteroduplexes; D009841:Oligonucleotides; D019920:Photoaffinity Labels; D051716:Replication Protein A; D013942:Thymine Nucleotides; D019951:DNA Polymerase beta; D004706:Endodeoxyribonucleases; D045585:Flap Endonucleases; C024157:thymidine 5'-triphosphate