title: PAX3 loads onto pericentromeric heterochromatin during S phase through PARP1.
abstract: BACKGROUND
  Proper re-establishment of heterochromatin after each round of DNA replication is critical to the preservation of cell identity. Paired box 3 (PAX3), a transcription factor important in embryonic development, was found to mediate the formation of pericentromeric heterochromatin. However, how PAX3 recognizes the heterochromatic environment and re-establishes it after DNA replication remains unclear.
  
  
  METHODS
  Cell-cycle synchronization, fluorescence microscopic analyses, and co-immunoprecipitation were used to analyze the heterochromatic localization of PAX3 in HEK 293 cells and NIH 3T3 cells.
  
  
  RESULTS
  We found that PAX3 binds pericentromeric heterochromatin during middle-to-late S phase. Loading of PAX3 onto pericentromeric heterochromatin requires poly(ADP-ribose) polymerase 1 (PARP1). Furthermore, loss of PAX3 or PARP1 delays cell-cycle progression through the S phase.
  
  
  CONCLUSIONS
  Our results reveal how PAX3 recognizes and maintains pericentromeric heterochromatin at the S phase of the cell cycle.
authors.affiliation: Department of Life Sciences, National Chung Hsing University, Taichung, Taiwan, R.O.C. Department of Applied Cosmetology, Hung Kuang University, Taichung, Taiwan, R.O.C.
authors.forename: Tsu-Fang
authors.initials: TF
authors.lastname: Wu
authors.affiliation: Department of Biotechnology, Asia University, Taichung, Taiwan, R.O.C.
authors.forename: Ya-Li
authors.initials: YL
authors.lastname: Yao
authors.affiliation: Institute of Molecular Biology, National Chung Hsing University, Taichung, Taiwan, R.O.C.
authors.forename: I-Lu
authors.initials: IL
authors.lastname: Lai
authors.affiliation: Department of Life Sciences, National Chung Hsing University, Taichung, Taiwan, R.O.C.
authors.forename: Tsung-Han
authors.initials: TH
authors.lastname: Lee
authors.affiliation: Experimental Oncology, Department of Oncology, University of Alberta, Cross Cancer Institute, Edmonton, AB, Canada.
authors.forename: D Alan
authors.initials: DA
authors.lastname: Underhill
authors.affiliation: Institute of Molecular Biology, National Chung Hsing University, Taichung, Taiwan, R.O.C. yangwm@nchu.edu.tw.
authors.forename: Wen-Ming
authors.initials: WM
authors.lastname: Yang
mesh_terms: D000818:Animals; D002453:Cell Cycle; D057809:HEK293 Cells; D006570:Heterochromatin / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D051379:Mice; D041681:NIH 3T3 Cells; D051761:Paired Box Transcription Factors / Q000235:genetics / Q000378:metabolism*; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism*; D011485:Protein Binding; D021381:Protein Transport; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D016196:S Phase
chemical_list: D006570:Heterochromatin; D051761:Paired Box Transcription Factors; D011993:Recombinant Fusion Proteins; D011065:Poly(ADP-ribose) Polymerases
keywords: PARP1; PAX3; S phase; pericentromeric heterochromatin