| First Author | Rassoulzadegan M | Year | 2000 |
| Journal | EMBO J | Volume | 19 |
| Issue | 13 | Pages | 3295-303 |
| PubMed ID | 10880442 | Mgi Jnum | J:63321 |
| Mgi Id | MGI:1860751 | Doi | 10.1093/emboj/19.13.3295 |
| Citation | Rassoulzadegan M, et al. (2000) Phagocytosis reveals a reversible differentiated state early in the development of the mouse embryo. EMBO J 19(13):3295-303 |
| abstractText | Mural trophectoderm cells of the mouse embryo possess a phagocytic potential as early as 3.5 days post coitum (d.p.c.). This first differentiated function shows a graded variation along the embryonic-abembryonic axis, from a maximal activity in the non-dividing cells of the abembryonic pole to a complete lack of activity in the replicating polar trophectoderm overlying the inner cell mass (ICM). This pattern can be explained by a negative control exerted by the ICM. Addition of FGF4, a factor secreted by ICM cells, strongly inhibited phagocytosis while inducing resumption of DNA synthesis in mural trophectoderm cells, revealing a reversible, FGF4-dependent differentiation state. Under conditions in which a small cluster of mural trophectoderm cells (<10) had internalized large particles, these otherwise morphologically normal embryos could not implant in the uterus, indicating that cells at the abembryonic pole have a critical role in initiating the implantation process. At post-implantation stages (6.5-8.5 d.p.c.), the ectoplacental cone and secondary giant cells derived from the polar trophectoderm also contained active phagocytes, but at that stage, differentiation was not reversed by FGF4. |
