title: Follicle microenvironment-associated alterations in gene expression in the mouse oocyte and its polar body.
abstract: OBJECTIVE
  To determine whether the follicle environment modulates oocyte-specific gene transcript levels in cultured oocytes and polar bodies (PBs).
  
  
  METHODS
  Animal study.
  
  
  METHODS
  Large academic research center.
  
  
  METHODS
  CD1 mice.
  
  
  METHODS
  In vitro growth of secondary mouse follicles in 0.25% or 1.5% alginate (ALG) in a three-dimensional culture system.
  
  
  METHODS
  Relative transcript levels of Gdf9, Bmp15, Nlrp5, Tcl1, and Zp3 were measured by real-time quantitative reverse transcriptase-polymerase chain reaction in oocytes during in vitro follicle development and oocyte maturation and in their first PBs after removal from metaphase II (MII) eggs.
  
  
  RESULTS
  All transcripts decreased earlier in oocytes cultured in 1.5% ALG compared with 0.25% ALG. Transcript levels were lower in MII eggs cultured in 1.5% ALG compared with in 0.25% ALG. All genes were expressed in PBs, and transcript levels were lower in PBs cultured in 1.5% ALG compared with in 0.25% ALG. Abundance of all transcripts was lower in PBs than in their sibling oocytes.
  
  
  CONCLUSIONS
  Local follicle environment modulates oocyte-specific gene expression in the oocyte and first PB. There is a significant difference in the transcript levels of oocyte-specific genes in PBs of 1.5% versus 0.25% ALG that correlates with ovarian environment-related decreases in oocyte competence.
authors: Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
authors: Ze-Xu
authors: ZX
authors: Jiao
authors: Teresa K
authors: TK
authors: Woodruff
mesh_terms: D000818:Animals; D000941:Antigens / Q000235:genetics; D055430:Bone Morphogenetic Protein 15 / Q000235:genetics; D060833:Cellular Microenvironment / Q000502:physiology*; D004527:Egg Proteins / Q000235:genetics; D005260:Female; D015870:Gene Expression / Q000502:physiology; D055429:Growth Differentiation Factor 9 / Q000235:genetics; D007247:Infertility, Female / Q000235:genetics / Q000503:physiopathology; D008540:Meiosis / Q000502:physiology; D008562:Membrane Glycoproteins / Q000235:genetics; D051379:Mice; D008815:Mice, Inbred Strains; D009865:Oocytes / Q000166:cytology* / Q000502:physiology*; D009924:Organ Culture Techniques; D006080:Ovarian Follicle / Q000166:cytology* / Q000254:growth & development / Q000502:physiology*; D059705:Polar Bodies / Q000502:physiology*; D011518:Proto-Oncogene Proteins / Q000235:genetics; D012333:RNA, Messenger / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000235:genetics; D000072216:Zona Pellucida Glycoproteins
chemical_list: D000941:Antigens; C525902:Bmp15 protein, mouse; D055430:Bone Morphogenetic Protein 15; D004527:Egg Proteins; C525898:Gdf9 protein, mouse; D055429:Growth Differentiation Factor 9; D008562:Membrane Glycoproteins; C416503:Nalp5 protein, mouse; D011518:Proto-Oncogene Proteins; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; C490393:Tcl1 protein, mouse; D000072216:Zona Pellucida Glycoproteins; C000606521:Zp3 protein, mouse