Fig 1: Distribution of CDX2 during the early stages of bovine development. (a) presents the specific changes in the CDX2 protein distribution from the 5-cell stage. Initially CDX2 was located in the cytoplasm of all cells and was absent in the nuclei. From 8-cell onwards CDX2 specifically allocated to the embryonic cell nuclei and became TE specific at the blastocyst stage. (b) shows a single optical section through the early stage blastocyst (7/8dpi) already presented in Figure 5a. At this stage CDX2 immunostaining was detected in the TE with some residual staining still visible in the ICM (highlighted by the dashed circle). DAPI marks chromatin. Confocal sections were taken every 3 µm.
Fig 2: CDX2 displays nuclear localisation and labels metaphase chromosomes. (a) presents 2 consecutive optical sections through an early bovine embryo double labelled for CDX2 and for histone lysine methylation H3K9me3. White arrow heads point to a typical heterochromatin distribution pattern at the periphery of the interphase nucleus. Green arrow heads indicate CDX2 and H3K9me3 colocalisation. Dashed circle in (a) highlights the metaphase plate. CDX2 signal overlays the chromosomes and colocalises with condensed, transcriptionally silent chromatin as indicated by H3K9me3 immunostaining enlarged in the right panel. (b) presents an optical scan through middle of late morula embryo (beginnings of cavity formation may be visible in top section of the embryo). CDX2 displays nuclear localisation and also labels the metaphase chromosomes (marked by the dashed white circle, the area is enlarged in the boxed panel). (c) HBl (9dpi) immunostained for CDX2. Dashed white circle highlights the metaphase plate where, the encircled area is enlarged in the boxed panel where the CDX2 signal colocalisation with metaphase chromosomes is visible. DAPI marks chromatin. Confocal sections were taken every 3 µm.
Fig 3: CDX2 immunolabelling controls. The binding specificity of the rabbit polyclonal anti CDX2 primary antibody (ab88129) (a) and mouse monoclonal anti CDX2 primary antibody (ab15258) (b) was verified with the use of blocking peptide (ab99158) prior to the antibody staining. The secondary antibodies used were goat anti-rabbit Rhodamine conjugated (sc-2091) in (a) and goat anti-mouse Rhodamine conjugated (sc-2092) in (b). Dashed circle marks the metaphase plate. DAPI labels chromatin.
Fig 4: ICM lineage segregation during bovine blastocyst formation. (a) presents a single optical section through an ICM of bovine early blastocyst (7dpi) immunostained for NANOG and OCT4. The boxed areas are enlarged in the bottom row. NANOG shows nuclear and OCT4 sub-nuclear localisation in ICM White arrows indicate cytoplasmic localisation of NANOG and OCT4 in the trophoblast cells in the vicinity of the ICM. Confocal sections were taken every 2 µm (b) shows a 3-D reconstruction of confocal images of an early blastocyst (7/8dpi) double labelled for CDX2 and OCT4. OCT4 was predominantly located in the ICM, but some signal was detected in the TE cells. Dashed circle marks the ICM. (c) is a 3-D compilation of optical sections taken through hatching blastocyst (8/9dpi) labelled for NANOG and OCT4. Dashed circle marks the ICM. (d) shows a 3-D reconstruction composed of 30 confocal sections (taken every 3 µm) through bovine hatched blastocyst (9dpi) double labelled for CDX2 and OCT4. At this stage OCT4 positive cells entirely segregate to the ICM. CDX2 becomes restricted to the trophoblast. DAPI marks chromatin. Confocal sections were taken every 3 µm.
Supplier Page from Abcam for Human CDX2 peptide