Comparative gene expression profiling of early porcine embryos derived from different in vivo and in vitro sources

• Author / Creator

  ZHOU, Chi

• There are strong interests in the factors that affect the efficient production of viable porcine embryos using either in vivo or in vitro production methods based on assisted reproductive technologies (ART). During the pre-implantation period of development, the porcine embryo exhibits dramatic changes and many key events of embryonic development take place. In this research, a series of studies were carried out in order to identify the critical regulators during the pre-implantation period of porcine embryonic development, and to identify the gene networks that are responsible for the impaired development of embryos produced after different ART manipulations. The detailed transcriptome profile of in vivo-derived “normal” pre-implantation porcine embryos has been characterized by transcriptomic profiling analysis of porcine oocytes and embryos representing nine different developmental stages from GV stage oocytes to day 11 embryos. Results from this research also suggest that the molecular events associated with embryonic genomic activation (EGA) in porcine pig embryos are probably initiated at, or before, the 4-cell stage. The embryo-activated genes “take-over” the majority of the mRNA profile from 8-cell stage onward, and the second wave of EGA probably peaks around the early blastocyst stage. Further comparative transcriptomic analysis between the in vivo hatched blastocysts (HB) and HB produced after in vitro ART manipulations (parthenogenetic activation (PA) and somatic cell chromatin transfer (CT)) revealed 1492 and 103 genes that differentially expressed of in PA and CT HB, respectively, in comparison with in vivo HB. Several significantly altered critical gene networks and pathways were identified in the PA- and CT-derived HB. In addition, apoptotic process was predicted to be activated in both PA and CT HB, and the activation of this apoptotic process is likely to be greater in PA HB. Finally, the effect of porcine luteinizing hormone-induced ovulation on the transcriptome of early porcine embryos was also investigated. Overall, result from this research provided useful information for the understanding of the molecular mechanism underlying early porcine embryonic development, and identified several critical genes / gene networks that are likely to contribute to the deficiencies of porcine embryos produced after different ART manipulations.

• Subjects / Keywords

  • Early porcine embryos
  • Assisted reproductive technology
  • Transcriptomic profiling

• Graduation date

  Spring 2014

• Type of Item

  Thesis

• Degree

  Doctor of Philosophy

• DOI

  https://doi.org/10.7939/R3319SB11

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.