title: Alteration of histone H3 lysine 4 trimethylation on putative lytic gene promoters by human Set1 complex during reactivation of Kaposi's sarcoma-associated herpesvirus.
abstract: OBJECTIVE
  Histone H3 lysine 4 is trimethylated by the human Set1 complex, which regulates the activation of gene expression. The aim of this study was to identify whether the levels of histone H3 lysine 4 trimethylation (H3K4me3) and the recruitment of human Set1 complex at the promoter regions of lytic genes quantitatively change during reactivation from latent to lytic infection of Kaposi's sarcoma-association herpesvirus (KSHV).
  
  
  METHODS
  During KSHV reactivation, global changes of H3K4 methylation in KSHV-infected cells were analyzed by Western blot. The relative levels of association between proteins and promoter regions were determined by chromatin immunoprecipitation assay and quantitative real-time PCR using specific antibodies and primer sets.
  
  
  RESULTS
  Our results showed that KSHV reactivation does not alter the overall cellular levels of H3K4 methylation. We observed that the switch from latency to lytic cycle leads to upregulation of H3K4me3 at the active lytic genes. We also found that the recruitment of RNA pol II and subunits of human Set1 complex were enriched at the same regions in response to KSHV reactivation.
  
  
  CONCLUSIONS
  These results demonstrate that the increase of H3K4me3 by human Set1 complex is involved in activation of lytic genes during the lytic infection of KSHV.
authors.affiliation: Department of Life Science, Dongguk University-Seoul, Seoul, South Korea.
authors.forename: Jae Eun
authors.initials: JE
authors.lastname: Jong
authors.forename: Seho
authors.initials: S
authors.lastname: Cha
authors.forename: Jun Hyeong
authors.initials: JH
authors.lastname: Jang
authors.forename: Taegun
authors.initials: T
authors.lastname: Seo
mesh_terms: D002460:Cell Line; D015967:Gene Expression Regulation, Viral; D019288:Herpesvirus 8, Human / Q000235:genetics / Q000502:physiology*; D011495:Histone-Lysine N-Methyltransferase / Q000378:metabolism*; D006657:Histones / Q000378:metabolism*; D006801:Humans; D008239:Lysine / Q000378:metabolism*; D008745:Methylation; D011401:Promoter Regions, Genetic; D015854:Up-Regulation; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism; D014775:Virus Activation / Q000502:physiology*; D017735:Virus Latency / Q000502:physiology
chemical_list: D006657:Histones; D014764:Viral Proteins; D011495:Histone-Lysine N-Methyltransferase; C526068:Setd1A protein, human; D008239:Lysine