Cdx2 expression begins at 3.5 days and is confined to the trophectoderm, being absent from the inner cell mass. From 8.5 days, Cdx2 begins to be expressed in embryonic tissues, principally in the posterior part of the gut from its earliest formation.[5]
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^Lohnes, David (2003). "The Cdx1 Homeodomain Protein: An Integrator of Posterior Signaling in the Mouse". BioEssays. 25 (10): 971–980. doi:10.1002/bies.10340. PMID14505364.
^Beck, F.; Erler, T.; Russell, A.; et al. (1995). "Expression of Cdx-2 in the Mouse Embryo and Placenta: Possible Role in Patterning of the Extra-embryonic Membranes". Developmental Dynamics. 204 (3): 219–227. doi:10.1002/aja.1002040302. PMID8573715. S2CID19576530.