GSE163427
Totipotency of mouse zygotes extends to single blastomeres of 4-cell stage embryos
In multicellular organisms, heterogametes of oocytes and sperms are fertilized and resulting zygotes give rise to new individuals. The ability of zygotes that produce a fully formed individual from single cell when placed in a supportive environment is defined as totipotency. Given that totipotent cells are the source of all multicellular organisms, better understanding of totipotency has a profound effect on not only biology but also our society. However, the exact distribution of totipotent cells in mammals remains elusive, although zygotes and single blastomeres at 2-cell stage embryos has been thought to be only mouse cells to be totipotent. We now show that a single blastomere isolated from 2- and 4-cell stage embryos gives rise to a fertile adult individual when it placed in a uterus, although isolation of blastomeres at these stage results in the disturbance of transcriptome in single blastomere derived embryos. Single blastomeres from 8-cell and morula stage embryos that were separately cultured in vitro exhibited severe defects in the formation of epiblast and primitive endoderm in the inner cell mass and the development to blastocysts, respectively. Our results thus indicate that totipotency of mouse zygotes extends to single blastomeres of 4-cell stage embryos. Overall design: Single-cell RNA sequencing of embryos with cavity derived from single blastomere of 1-, 2-, 4-, and 8-cell stage embryos.