Naive stem cell blastocyst model captures human embryo lineage segregation.
Ontology highlight
ABSTRACT:
SUBMITTER: Yanagida A
PROVIDER: S-EPMC8189436 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:ObjectivesGene regulation in early embryos has been widely studied for a long time because lineage segregation gives rise to the formation of a pluripotent cell population, known as the inner cell mass (ICM), during pre-implantation embryo development. The extraordinarily longer pre-implantation embryo development in pigs leads to the distinct features of the pluripotency network compared with mice and humans. For these reasons, a comparative study using pre-implantation pig embryos would provide new insights into the mammalian pluripotency network and help to understand differences in the roles and networks of genes in pre-implantation embryos between species.Materials and methodsTo analyse the functions of SOX2 in lineage segregation and cell proliferation, loss- and gain-of-function studies were conducted in pig embryos using an overexpression vector and the CRISPR/Cas9 system. Then, we analysed the morphological features and examined the effect on the expression of downstream genes through immunocytochemistry and quantitative real-time PCR.ResultsOur results showed that among the core pluripotent factors, only SOX2 was specifically expressed in the ICM. In SOX2-disrupted blastocysts, the expression of the ICM-related genes, but not OCT4, was suppressed, and the total cell number was also decreased. Likewise, according to real-time PCR analysis, pluripotency-related genes, excluding OCT4, and proliferation-related genes were decreased in SOX2-targeted blastocysts. In SOX2-overexpressing embryos, the total blastocyst cell number was greatly increased but the ICM/TE ratio decreased.ConclusionsTaken together, our results demonstrated that SOX2 is essential for ICM formation and cell proliferation in porcine early-stage embryogenesis.
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