title: Fully-mature antral mouse oocytes are transcriptionally silent but their heterochromatin maintains a transcriptional permissive histone acetylation profile.
abstract: OBJECTIVE
  The final stages of antral mouse oocytes maturation are characterised by the transition from transcriptionally active NSN to inactive SN oocytes. Here, we studied the profile of histone acetylation changes occurring during the NSN-to-SN transition.
  
  
  METHODS
  During the NSN-to-SN transition, oocytes were classified based on their chromatin organisation and the immunocytochemical profile of histones H2B, H3 and H4 acetylation was analysed.
  
  
  RESULTS
  We described four patterns of immunostaining common to the three acetylated histones, corresponding to stages of progressive localisation: From a diffused distribution in NSN oocytes to the association with constitutive heterochromatin and then to the nucleolar surface region in SN oocytes.
  
  
  CONCLUSIONS
  The maintenance of a favourable transcriptional epigenetic context, in the heterochromatin of transcriptionally silent SN oocytes, might be related to the early stages of development when transcripts from these heterochromatic regions are functional to preimplantation progression.
authors.affiliation: Sezione di Istologia ed Embriologia, Dipartimento di Medicina Sperimentale, Universita' degli Studi di Parma, Parma, Italy. maurizio.zuccotti@unipr.it
authors.forename: Maurizio
authors.initials: M
authors.lastname: Zuccotti
authors.forename: Michele
authors.initials: M
authors.lastname: Bellone
authors.forename: Frank
authors.initials: F
authors.lastname: Longo
authors.forename: Carlo Alberto
authors.initials: CA
authors.lastname: Redi
authors.forename: Silvia
authors.initials: S
authors.lastname: Garagna
mesh_terms: D000107:Acetylation; D000818:Animals; D005260:Female; D020868:Gene Silencing; D006570:Heterochromatin / Q000235:genetics / Q000378:metabolism*; D006657:Histones / Q000378:metabolism*; D051379:Mice; D008815:Mice, Inbred Strains; D009865:Oocytes / Q000166:cytology* / Q000378:metabolism; D014158:Transcription, Genetic
chemical_list: D006570:Heterochromatin; D006657:Histones