title: Telomeric proteins regulate episomal maintenance of Epstein-Barr virus origin of plasmid replication.
abstract: Episomal maintenance and DNA replication of EBV origin of plasmid replication (OriP) plasmid maintenance is mediated by the viral encoded origin binding protein, EBNA1, and unknown cellular factors. We found that telomeric repeat binding factor 2 (TRF2), TRF2-interacting protein hRap1, and the telomere-associated poly(ADP-ribose) polymerase (Tankyrase) bound to the dyad symmetry (DS) element of OriP in an EBNA1-dependent manner. TRF2 bound cooperatively with EBNA1 to the three nonamer sites (TTAGGGTTA), which resemble telomeric repeats. Mutagenesis of the nonamers reduced plasmid maintenance function and increased plasmid sensitivity to genotoxic stress. DS affinity-purified proteins possessed poly(ADP-ribose) polymerase (PARP) activity, and EBNA1 was subject to NAD-dependent posttranslational modification in vitro. OriP plasmid maintenance was sensitive to changes in cellular PARP/Tankyrase activity. These findings imply that telomere-associated proteins regulate OriP plasmid maintenance by PAR-dependent modifications.
authors.affiliation: The Wistar Institute, 3601 Spruce Street, Philadelphia, PA 19104, USA.
authors.forename: Zhong
authors.initials: Z
authors.lastname: Deng
authors.forename: Larissa
authors.initials: L
authors.lastname: Lezina
authors.forename: Chi-Ju
authors.initials: CJ
authors.lastname: Chen
authors.forename: Svetlana
authors.initials: S
authors.lastname: Shtivelband
authors.forename: Wingkan
authors.initials: W
authors.lastname: So
authors.forename: Paul M
authors.initials: PM
authors.lastname: Lieberman
mesh_terms: D002846:Chromatography, Affinity / Q000379:methods; D004247:DNA / Q000235:genetics / Q000378:metabolism; D004261:DNA Replication / Q000502:physiology; D004268:DNA-Binding Proteins / Q000302:isolation & purification / Q000378:metabolism; D019309:Epstein-Barr Virus Nuclear Antigens / Q000302:isolation & purification / Q000378:metabolism*; D004854:Herpesvirus 4, Human / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D010957:Plasmids / Q000235:genetics* / Q000378:metabolism; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D011485:Protein Binding; D020449:Repetitive Sequences, Amino Acid; D018741:Replication Origin / Q000502:physiology*; D000089804:Shelterin Complex; D038501:Tankyrases; D016615:Telomere / Q000235:genetics / Q000378:metabolism; D034501:Telomere-Binding Proteins; D035341:Telomeric Repeat Binding Protein 2; D014407:Tumor Cells, Cultured
chemical_list: D004247:DNA; D004268:DNA-Binding Proteins; D019309:Epstein-Barr Virus Nuclear Antigens; D011065:Poly(ADP-ribose) Polymerases; D000089804:Shelterin Complex; D038501:Tankyrases; D034501:Telomere-Binding Proteins; D035341:Telomeric Repeat Binding Protein 2; C440809:TERF2IP protein, human; C418109:TNKS protein, human; C417029:EBV-encoded nuclear antigen 1