title: Identification of genes expressed in primate primordial oocytes.
abstract: BACKGROUND
  The factors involved in oocyte survival and transition from quiescence to the growing phenotype remain unknown. Herein we report genes that are differentially expressed in the primordial oocyte revealed by DNA arrays.
  
  
  METHODS
  Primordial oocytes were captured selectively in rhesus monkey ovary sections using laser capture microdissection. The RNA was extracted and amplified in two rounds by T7-based linear RNA amplification, fluorescence labelled and then hybridized to human cDNA arrays containing 7680 elements. RNA from human placenta served as a reference sample.
  
  
  RESULTS
  Ninety-five genes were found to be consistently expressed at a higher level in primordial oocytes. Expression of several of these genes in the oocyte has been reported before, e.g. deleted in azoospermia (DAZ), prohibitin and transglutaminase 2. Oocyte expression of several novel transcripts revealed on array hybridization, such as gene 33, ubiquitin-conjugating enzyme E2A, G1 to S phase transition 1, growth arrest and DNA damage-inducible (GADD), and dendritic cell-derived ubiquitin-like protein (DC-UbP) was confirmed by in situ hybridization. Some array-identified gene products [integrin beta3, alpha-tubulin, regulatory telomere elongation protein (RAP1) and cellular repressor of EIA-stimulated genes (CREG protein)] were detected in human oocytes by immunofluorescence. Bioinformatic analysis of the oocyte-enriched transcripts reveals a functional profile summarized as follows: cell cycle (14%); transporter (13%); signal transduction (10%); cytoskeletal (7%); transcription factor (5%); immune response (5%); apoptosis-related (5%); RNA processing (5%); and the remainder of miscellaneous categories.
  
  
  CONCLUSIONS
  These observations may contribute to the elucidation of molecular pathways involved in oocyte survival and maturation.
authors.affiliation: DEB, NICHD, NIH, Bethesda, MD 20892, USA.
authors.forename: Jose A
authors.initials: JA
authors.lastname: Arraztoa
authors.forename: Jian
authors.initials: J
authors.lastname: Zhou
authors.forename: David
authors.initials: D
authors.lastname: Marcu
authors.forename: Clara
authors.initials: C
authors.lastname: Cheng
authors.forename: Robert
authors.initials: R
authors.lastname: Bonner
authors.forename: Mei
authors.initials: M
authors.lastname: Chen
authors.forename: Charlie
authors.initials: C
authors.lastname: Xiang
authors.forename: Michael
authors.initials: M
authors.lastname: Brownstein
authors.forename: Kevin
authors.initials: K
authors.lastname: Maisey
authors.forename: Monica
authors.initials: M
authors.lastname: Imarai
authors.forename: Carolyn
authors.initials: C
authors.lastname: Bondy
mesh_terms: D000818:Animals; D030541:Databases, Genetic; D005260:Female; D020869:Gene Expression Profiling; D008253:Macaca mulatta; D020411:Oligonucleotide Array Sequence Analysis; D009865:Oocytes / Q000166:cytology* / Q000502:physiology*; D006080:Ovarian Follicle / Q000166:cytology / Q000502:physiology