title: Transcriptome profiling of human pre-implantation development.
abstract: BACKGROUND
  Preimplantation development is a crucial step in early human development. However, the molecular basis of human preimplantation development is not well known.
  
  
  METHODS
  By applying microarray on 397 human oocytes and embryos at six developmental stages, we studied the transcription dynamics during human preimplantation development.
  
  
  RESULTS
  We found that the preimplantation development consisted of two main transitions: from metaphase-II oocyte to 4-cell embryo where mainly the maternal genes were expressed, and from 8-cell embryo to blastocyst with down-regulation of the maternal genes and up-regulation of embryonic genes. Human preimplantation development proved relatively autonomous. Genes predominantly expressed in oocytes and embryos are well conserved during evolution.
  
  
  CONCLUSIONS
  Our database and findings provide fundamental resources for understanding
authors.affiliation: Department of Bioscience and Nutrition, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Pu
authors.initials: P
authors.lastname: Zhang
authors.forename: Marco
authors.initials: M
authors.lastname: Zucchelli
authors.forename: Sara
authors.initials: S
authors.lastname: Bruce
authors.forename: Fredwell
authors.initials: F
authors.lastname: Hambiliki
authors.forename: Anneli
authors.initials: A
authors.lastname: Stavreus-Evers
authors.forename: Lev
authors.initials: L
authors.lastname: Levkov
authors.forename: Heli
authors.initials: H
authors.lastname: Skottman
authors.forename: Erja
authors.initials: E
authors.lastname: Kerkelä
authors.forename: Juha
authors.initials: J
authors.lastname: Kere
authors.forename: Outi
authors.initials: O
authors.lastname: Hovatta
mesh_terms: D001755:Blastocyst / Q000378:metabolism*; D010064:Embryo Implantation / Q000235:genetics; D004622:Embryo, Mammalian / Q000378:metabolism; D047108:Embryonic Development / Q000235:genetics; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D006801:Humans; D020411:Oligonucleotide Array Sequence Analysis; D009865:Oocytes / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism*; D013997:Time Factors
chemical_list: D012333:RNA, Messenger