title: DAXX modulates human papillomavirus early gene expression and genome replication in U2OS cells.
abstract: BACKGROUND
  The human papillomavirus (HPV) genomes can replicate, and are maintained as autonomously replicating extrachromosomal plasmids in human U2OS cells. Previous studies have shown that HPV genomes are transcriptionally active in U2OS cells and can express the viral early proteins required for initiation and establishment of HPV replication. In the present work, we have examined the involvement of cellular DAXX protein in HPV replication in U2OS cells.
  
  
  METHODS
  We have used indirect immunofluorescence and FISH analysis in order to study HPV replication compartments in U2OS cells. In addition, we have used siRNA knock-down for examining the effect of the DAXX protein on HPV replication and transcription in U2OS cells.
  
  
  RESULTS
  We show that a portion of HPV replication foci are partially co-localized with components of ND10, cellular DAXX and PML proteins. In addition, we demonstrate that the knock-down of the cellular DAXX protein modulates the HPV genome replication and transcription in U2OS cells--papillomavirus replication is reduced in the absence of this component of ND10.
  
  
  CONCLUSIONS
  The DAXX protein modulates the early gene expression and the transient replication of HPV genomes in U2OS cells.
authors.affiliation: Institute of Technology, University of Tartu, Nooruse 1, 50411, Tartu, Estonia. piia.kivipold@gmail.com.
authors.forename: Piia
authors.initials: P
authors.lastname: Kivipõld
authors.affiliation: Institute of Technology, University of Tartu, Nooruse 1, 50411, Tartu, Estonia. liisi.vosa@ut.ee.
authors.forename: Liisi
authors.initials: L
authors.lastname: Võsa
authors.affiliation: Institute of Technology, University of Tartu, Nooruse 1, 50411, Tartu, Estonia. mart.ustav@ut.ee.
authors.forename: Mart
authors.initials: M
authors.lastname: Ustav
authors.affiliation: Institute of Technology, University of Tartu, Nooruse 1, 50411, Tartu, Estonia. reet.kurg@ut.ee.
authors.forename: Reet
authors.initials: R
authors.lastname: Kurg
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000378:metabolism*; D002460:Cell Line; D056970:Co-Repressor Proteins; D019084:Fluorescent Antibody Technique, Indirect; D015967:Gene Expression Regulation, Viral; D055785:Gene Knockdown Techniques; D054884:Host-Pathogen Interactions; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D018832:Molecular Chaperones; D009687:Nuclear Proteins / Q000378:metabolism*; D027383:Papillomaviridae / Q000502:physiology*; D014779:Virus Replication
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D056970:Co-Repressor Proteins; C106985:DAXX protein, human; D018832:Molecular Chaperones; D009687:Nuclear Proteins