RT Journal Article
SR Electronic
T1 The role of <em>Cdx2</em> as a lineage specific transcriptional repressor for pluripotent network during trophectoderm and inner cell mass specification
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 124438
DO 10.1101/124438
A1 Daosheng Huang
A1 Xiaoping Han
A1 Ping Yuan
A1 Amy Ralston
A1 Lingang Sun
A1 Mikael Huss
A1 Tapan Mistri
A1 Luca Pinello
A1 Huck Hui Ng
A1 Guocheng Yuan
A1 Junfeng Ji
A1 Janet Rossant
A1 Paul Robson
A1 Guoji Guo
YR 2017
UL http://biorxiv.org/content/early/2017/04/06/124438.abstract
AB The first cellular differentiation event in mouse development leads to the formation of the blastocyst consisting of the inner cell mass (ICM) and an outer functional epithelium called trophectoderm (TE). The lineage specific transcription factor CDX2 is required for proper TE specification, where it promotes expression of TE genes, and represses expression of Pou5f1 (OCT4) by inhibiting OCT4 from promoting its own expression. However its downstream network in the developing early embryo is not fully characterized. Here, we performed high-throughput single embryo qPCR analysis in Cdx2 null embryos to identify components of the CDX2-regulated network in vivo. To identify genes likely to be regulated by CDX2 directly, we performed CDX2 ChIP-Seq on trophoblast stem (TS) cells, derived from the TE. In addition, we examined the dynamics of gene expression changes using an inducible CDX2 embryonic stem (ES) cell system, so that we could predict which CDX2-bound genes are activated or repressed by CDX2 binding. By integrating these data with observations of chromatin modifications, we were able to identify novel regulatory elements that are likely to repress gene expression in a lineage-specific manner. Interestingly, we found CDX2 binding sites within regulatory elements of key pluripotent genes such as Pou5f1 and Nanog, pointing to the existence of a novel mechanism by which CDX2 maintains repression of OCT4 in trophoblast. Our study proposes a general mechanism in regulating lineage segregation during mammalian development.