First Author | Home P | Year | 2009 |
Journal | J Biol Chem | Volume | 284 |
Issue | 42 | Pages | 28729-37 |
PubMed ID | 19700764 | Mgi Jnum | J:157815 |
Mgi Id | MGI:4436998 | Doi | 10.1074/jbc.M109.016840 |
Citation | Home P, et al. (2009) GATA3 is selectively expressed in the trophectoderm of peri-implantation embryo and directly regulates Cdx2 gene expression. J Biol Chem 284(42):28729-37 |
abstractText | During early mammalian development, genesis of the first two cell lineages, inner cell mass (ICM) and trophectoderm (TE), is dependent upon functions of key transcription factors that are expressed in a regulated and spatially restricted fashion. In this study, we demonstrate that during early mouse development, mRNA expression of transcription factor GATA3 is induced at the 4-cell stage and is consistently present during pre-implantation embryonic development. Interestingly, at the blastocyst stage, Gata3 mRNA is selectively up-regulated within the TE lineage, and GATA3 protein is abundantly present only in the TE but not in the ICM. Using mouse trophoblast stem cells (TS cells) as a model, we found that, knockdown of GATA3 by RNA interference (RNAi) down-regulates expression of caudal-type homeobox 2 (CDX2), a key regulator of the TE lineage. Chromatin immunoprecipitation (ChIP) analyses revealed that, in TS cells, GATA3 directly regulates Cdx2 transcription from a conserved GATA motif at the intron 1 region of the Cdx2 locus. ChIP analyses with mouse blastocysts also detected GATA3 occupancy at intron 1 of the Cdx2 locus. In addition, down-regulation of GATA3 in pre-implantation mouse embryos reduces Cdx2 expression and inhibits morula to blastocyst transformation. Our results indicate a novel function of GATA3, in which it is selectively expressed in TE, regulates expression of key genes in TE lineage, and is involved in morula to blastocyst transformation. |