First published online April 13, 2005
Development 132, 901e (2005)
© The Company of Biologists Limited
Cdx2: controlling early lineage segregation
The first two cell lineages of the mammalian embryo - the inner cell mass
(ICM) and the trophectoderm - segregate at the blastocyst stage. While the
transcription factors Oct4 and Nanog positively regulate commitment to the ICM
lineage, the positive regulators of trophectoderm cell fate remain unknown.
Strumpf and colleagues now report that the homeodomain protein Cdx2 and the
T-box protein Eomes are required at distinct stages during trophectoderm
lineage development in mice (see p.
2093). Their studies
of homozygous mutant embryos reveal that Eomes is required for
trophectoderm differentiation and proliferation beyond the expanded blastocyst
stage, while Cdx2 is essential for trophectoderm function, for
establishment of the trophoblast lineage, and for restriction of Oct4
and Nanog expression to the ICM lineage. Thus, Cdx2 is the
earliest known transcription factor involved in trophectoderm specification
and is essential for the segregation of the ICM and trophectoderm
lineages.
Related articles in Development:
- Cdx2 is required for correct cell fate specification and differentiation of trophectoderm in the mouse blastocyst
- Dan Strumpf, Chai-An Mao, Yojiro Yamanaka, Amy Ralston, Kallayanee Chawengsaksophak, Felix Beck, and Janet Rossant
Development 2005 132: 2093-2102.
[Abstract]
[Full Text]
