title: Discovery of porcine maternal factors related to nuclear reprogramming and early embryo development by proteomic analysis.
abstract: BACKGROUND
  Differentiated cell nuclei can be reprogrammed to a pluripotent state in several ways, including incubation with oocyte extracts, transfer into enucleated oocytes, and induced pluripotent stem cell technology. Nuclear transfer-mediated reprogramming has been proven to be the most efficient method. Maternal factors stored in oocytes have critical roles on nuclear reprogramming and early embryo development, but remain elusive.
  
  
  RESULTS
  In this study, we showed most of porcine oocytes became nuclear matured at 33 h of IVM and the rate had no significant difference with oocytes at 42 h of IVM (p > 0.05). Moreover, the cleavage and blastocyst rates of SCNT and PA embryos derived from 42O were significantly higher than that of 33O (p < 0.05). But 33O could sustain IVF embryo development with higher cleavage and blastocyst rates comparing to 42O (p < 0.05). To clarify the development potential difference between 33O and 42O, 18 differentially expressed proteins were identified by proteomic analysis, and randomly selected proteins were confirmed by Western blot. Bioinformatic analysis of these proteins revealed that 33O highly synthesized proteins related to fertilization, and 42O was rich in nuclear reprogramming factors.
  
  
  CONCLUSIONS
  These results present a unique insight into maternal factors related to nuclear reprogramming and early embryo development.
authors.affiliation: College of Life Science, Northeast Forestry University, 26 Hexing Road, Xiangfang Dist., Harbin, Helongjiang 150040 China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Zhao
authors.affiliation: College of Life Science, Northeast Forestry University, 26 Hexing Road, Xiangfang Dist., Harbin, Helongjiang 150040 China.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Guo
authors.affiliation: College of Life Science, Northeast Forestry University, 26 Hexing Road, Xiangfang Dist., Harbin, Helongjiang 150040 China.
authors.forename: Shanhua
authors.initials: S
authors.lastname: Piao
authors.affiliation: College of Life Science, Northeast Forestry University, 26 Hexing Road, Xiangfang Dist., Harbin, Helongjiang 150040 China.
authors.forename: Chunsheng
authors.initials: C
authors.lastname: Wang
authors.affiliation: College of Life Science, Northeast Forestry University, 26 Hexing Road, Xiangfang Dist., Harbin, Helongjiang 150040 China.
authors.forename: Tiezhu
authors.initials: T
authors.lastname: An
keywords: IVF; Maternal factors; Nuclear transfer; Proteomics