2011 Fiscal Year Final Research Report

Mechanism for the acquisition of totipotency by Yamanaka factors

Research Project

Project/Area Number	22658091
Research Category	Grant-in-Aid for Challenging Exploratory Research
Allocation Type	Single-year Grants
Research Field	Basic veterinary science/Basic zootechnical science
Research Institution	The University of Tokyo
Principal Investigator	AOKI Fugaku 東京大学, 大学院・新領域創成科学研究科, 教授 (20175160)
Project Period (FY)	2010 – 2011
Keywords	卵 / 初期胚 / リプログラミング
Research Abstract	The expression of the transcripts of Yamanaka factors was examined by RT-PCR, which revealed that all of the factors were detected in the preimplantation embryos. Since the expression levels of Oct3/4 and c-Myc seemed to be high, I focused on these genes in the further experiments. Immunocytochemistry revealed that the nuclear localization of both of OCT3/4 and c-MYC proteins increased after fertilization. When full-grown oocytes were microinjected with Oct3/4 siRNA and then subjected to in vitro fertilization, the fertilized oocytes did not cleave to the 2-cell stage. In these oocytes, the expressions of the genes which are usually expressed after fertilization were reduced.