title: The Effects of Polyadenylation Status on MPFs During In Vitro Porcine Oocyte Maturation.
abstract: OBJECTIVE
  This study aims to clarify the effects of polyadenylation status on M-phase promoting factors (MPFs) during in vitro porcine oocyte maturation.
  
  
  METHODS
  In this study, porcine follicular oocytes from large follicles (> 5 millimeter (mm)) and small follicles (< 3 mm) were examined at different follicular developmental stages. The polyadenylation of maternal mRNAs was inhibited by the addition of 3'-deoxyadenosine (3'-da) during the germinal vesicle (GV)(0 h), GV breakdown (GVBD)(18 h), metaphase I (MI)(28 h), and metaphase II (MII) (44 h) stages. In addition, the expression levels and poly-(A) tail lengths of the maternal mRNAs Cyclin B1 and cell division cycle 2 (Cdc2) were determined by real-time quantitative PCR. Immunofluorescence was used to assess spindle formation and chromosome alignment in the examined oocytes.
  
  
  RESULTS
  In large-follicle oocytes, the effects of inhibiting polyadenylation caused the percentage of mature to be significantly lower for the treated group than for the untreated group (p < 0.01). 3'-da can significantly improve the rate of small oocyte maturation in vitro and inhibits Cdc2 polyadenylation. Cyclin B1 plays a significant role in promoting the maturation of large-follicle oocytes. Polyadenylation contributes to the formation of dominant follicles and facilitates the selection of dominant follicles. However, the inhibition of adenylation affected spindle formation-related propulsion and chromosome alignment in both large- and small-follicle oocytes. The first polar body could not be extruded in certain large follicles.
  
  
  CONCLUSIONS
  3'-da can significantly improve the rate of small oocyte maturation in vitro, but it can also affect spindle formation-related propulsion and chromosome alignment.
authors.affiliation: Laboratory Animal Center, College of Animal Sciences, Jilin University, Changchun, China.
authors.forename: Huiyu
authors.initials: H
authors.lastname: Liu
authors.forename: Yan
authors.initials: Y
authors.lastname: Gao
authors.forename: Bo
authors.initials: B
authors.lastname: Zhai
authors.forename: Hao
authors.initials: H
authors.lastname: Jiang
authors.forename: Yu
authors.initials: Y
authors.lastname: Ding
authors.forename: Lianjiang
authors.initials: L
authors.lastname: Zhang
authors.forename: Changhong
authors.initials: C
authors.lastname: Li
authors.forename: Qiong
authors.initials: Q
authors.lastname: Deng
authors.forename: Xianfeng
authors.initials: X
authors.lastname: Yu
authors.forename: Jiabao
authors.initials: J
authors.lastname: Zhang
mesh_terms: D000818:Animals; D016203:CDC2 Protein Kinase / Q000235:genetics* / Q000378:metabolism; D020090:Chromosome Segregation / Q000187:drug effects; D056744:Cyclin B1 / Q000235:genetics* / Q000378:metabolism; D003839:Deoxyadenosines / Q000494:pharmacology; D005260:Female; D059471:In Vitro Oocyte Maturation Techniques; D008677:Metaphase; D009865:Oocytes / Q000187:drug effects / Q000276:immunology / Q000378:metabolism* / Q000648:ultrastructure; D006080:Ovarian Follicle / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D026723:Polyadenylation / Q000187:drug effects*; D061251:Primary Cell Culture; D012333:RNA, Messenger / Q000235:genetics* / Q000378:metabolism; D008941:Spindle Apparatus / Q000187:drug effects / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure; D013552:Swine
chemical_list: D056744:Cyclin B1; D003839:Deoxyadenosines; D012333:RNA, Messenger; D016203:CDC2 Protein Kinase; C058120:cordycepin