Earticle

초록

영어

Embryonic genome activation (EGA) is the first major transition that occurs after fertilization, and entails a dramatic reprogramming of gene expression that is essential for continued development. Although it has been suggested that EGA in porcine embryos starts at the four-cell stage, recent evidence indicates that EGA may commence even earlier; however, the molecular details of EGA remain incompletely understood. The RNA polymerase II of eukaryotes transcribes mRNAs and most small nuclear RNAs. The largest subunit of RNA polymerase II can become phosphorylated in the C-terminal domain. The unphosphorylated form of the RNA polymerase II largest subunit C-terminal domain (IIa) plays a role in initiation of transcription, and the phosphorylated form (IIo) is required for transcriptional elongation and mRNA splicing. In the present study, we explored the nuclear translocation, nuclear localization, and phosphorylation dynamics of the RNA polymerase II C-terminal domain in immature pig oocytes, mature oocytes, two-, four-, and eight-cell embryos, and the morula and blastocyst. To this end, we used antibodies specific for the IIa and IIo forms of RNA polymerase II to stain the proteins. Unphosphorylated RNA polymerase II stained strongly in the nuclei of germinal vesicle oocytes, whereas the phosphorylated form of the enzyme was confined to the chromatin of prophase I oocytes. After fertilization, both unphosphorylated and phosphorylated RNA polymerase II began to accumulate in the nuclei of early stage one-cell embryos, and this pattern was maintained through to the blastocyst stage. The results suggest that both porcine oocytes and early embryos are transcriptionally competent, and that transcription of embryonic genes during the first three cell cycles parallels expression of phosphorylated RNA polymerase II.

목차

ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
  Oocyte and Embryo Production
  Immunostaining and Confocal Microscopy
  Immunocytochemistry and Confocal Microscopy
 RESULTS
  Accumulation of RNA Polymerase II during Oocyte Maturation
  Nuclear Accumulation of RNA Polymerase II in Zygotesat the One-Cell Stage
  RNA Polymerase in the Nucleus at Later Embryonic Stages
 DISCUSSION
 REFERENCES

키워드

저자

• Reza Oqani [ Department of Animal Science & Biotechnology, Research Center for Transgenic Cloned Pigs, Chungnam National University ]
• Min Gu Lee [ Department of Animal Science & Biotechnology, Research Center for Transgenic Cloned Pigs, Chungnam National University ]
• Lin Tao [ Department of Animal Science & Biotechnology, Research Center for Transgenic Cloned Pigs, Chungnam National University ]
• Dong Il Jin [ Department of Animal Science & Biotechnology, Research Center for Transgenic Cloned Pigs, Chungnam National University ] Corresponding author

참고문헌

발행기관

간행물

표지보기 관심저널 등록

• 간행물명

  Reproductive & developmental biology

• 간기

  계간

• pISSN

  1738-2432

• eISSN

  2288-0151

• 수록기간

  1977~2018

• 십진분류

  KDC 527 DDC 636