Noninvasive visualization of molecular events in the mammalian zygote.
Following fertilization, a number of molecular events are triggered in the mammalian zygote. As biochemical studies using mammalian gametes and zygotes have inherent difficulties, the molecular nature of these processes is currently unclear. We have developed a method to visualize these events. In vitro transcribed mRNAs encoding for proteins fused with green fluorescent protein were microinjected into oocytes or embryos and fluorescence signals were observed. Using this technique we succeeded in obtaining images of the DNA methylation status in living mouse and rabbit embryos. Moreover, time-lapse images were acquired of spindle and nuclear formation during second meiosis and first mitosis. Importantly, the microinjected embryos developed to the normal offspring even after observation, suggesting that the technique is relatively noninvasive. Thus, our method may help elucidate the molecular aspects of fertilization and preimplantation development and, based on the real-time genetic and epigenetic status, could become a tool to select "good quality" embryos before implantation.
Yamagata
Kazuo
K
Graduate School of Life and Environmental Science, and Institute of Applied Biochemistry, University of Tsukuba,Tsukuba Science City, Ibaraki, Japan. kazuo@agbi.tsukuba.ac.jp
Yamazaki
Taiga
T
Yamashita
Misuzu
M
Hara
Yuki
Y
Ogonuki
Narumi
N
Ogura
Atsuo
A
D000818:Animals; D019175:DNA Methylation; D047108:Embryonic Development; D049452:Green Fluorescent Proteins / Q000032:analysis* / Q000235:genetics; D049408:Luminescent Agents / Q000032:analysis*; D051379:Mice; D008856:Microscopy, Fluorescence; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000235:genetics; D011817:Rabbits; D011993:Recombinant Fusion Proteins / Q000032:analysis / Q000235:genetics; D014162:Transfection; D015053:Zygote / Q000737:chemistry* / Q000166:cytology* / Q000254:growth & development
D049408:Luminescent Agents; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; D049452:Green Fluorescent Proteins