Changes in the Expression Patterns of the Genes Involved in the Segregation
and Function of Inner Cell Mass and Trophectoderm Lineages During Porcine Preimplantation
Development |
| |
Authors: | Takashi FUJII Nobuyuki SAKURAI Tsubasa OSAKI Gentaro IWAGAMI Hiroki HIRAYAMA Akira MINAMIHASHI Tsutomu HASHIZUME Ken SAWAI |
| |
Institution: | 1)Faculty of Agriculture, Iwate University, Iwate 020-8550, Japan;2)Animal Research Center, Hokkaido Research Organization, Hokkaido 081-0038, Japan |
| |
Abstract: | In mouse embryos, segregation of the inner cell mass (ICM) and trophectoderm (TE)
lineages is regulated by genes, such as OCT-4, CDX2 and
TEAD4. However, the molecular mechanisms that regulate the segregation
of the ICM and TE lineages in porcine embryos remain unknown. To obtain insights regarding
the segregation of the ICM and TE lineages in porcine embryos, we examined the mRNA
expression patterns of candidate genes, OCT-4, CDX2,
TEAD4, GATA3, NANOG,
FGF4, FGFR1-IIIc and FGFR2-IIIc, in
blastocyst and elongated stage embryos. In blastocyst embryos, the expression levels of
OCT-4, FGF4 and FGFR1-IIIc were
significantly higher in the ICM than in the TE, while the CDX2,
TEAD4 and GATA3 levels did not differ between the ICM
and TE. The expression ratio of CDX2 to OCT-4
(CDX2/OCT-4) also did not differ between the ICM and
TE at the blastocyst stage. In elongated embryos, OCT-4,
NANOG, FGF4 and FGFR1-IIIc were
abundantly expressed in the embryo disc (ED; ICM lineage), but their expression levels
were very low in the TE. In contrast, the CDX2, TEAD4
and GATA3 levels were significantly higher in the TE than in the ED. In
addition, the CDX2/OCT-4 ratio was markedly higher in
the TE than in the ED. We demonstrated that differences in the expression levels of
OCT-4, CDX2, TEAD4,
GATA3, NANOG, FGF4,
FGFR1-IIIc and FGFR2-IIIc genes between ICM and TE
lineages cells become more clear during development from porcine blastocyst to elongated
embryos, which indicates the possibility that in porcine embryos, functions of ICM and TE
lineage cells depend on these gene expressions proceed as transition from blastocyst to
elongated stage. |
| |
Keywords: | Elongated embryo Gene expression Inner cell mass Porcine embryo Trophectoderm |
|
|