Send to

Choose Destination
Anat Rec. 1992 Jan;232(1):141-9.

Basement membrane and fibronectin matrix are distinct entities in the developing mouse blastocyst.

Author information

Department of Cell Biology, Gulbenkian Institute of Science, Oeiras, Portugal.


Immunocytochemical techniques were used to study the distribution of fibronectin, type IV collagen (collagen-IV), and laminin in four different stages of mouse blastocyst development. Immunoreactivity for collagen-IV and laminin is present in a granular pattern inside the inner cell mass (ICM) cells in stage 1 blastocysts, while these blastocysts are negative for fibronectin. Fibronectin immunoreactivity appears extracellularly under the trophectoderm (TE) in stage 2 blastocysts, in the form of homogeneously distributed dots, and/or fibrils located preferentially close to cell boundaries. It is followed by the appearance of both collagen-IV and laminin immunoreactivity in patches on the basal side of the TE in stage 3 blastocysts. These patches are initially localized under the central region of TE cells, thus in a location clearly different from that of fibronectin-positive fibrils. As development proceeds the collagen-IV- and laminin-positive patches become larger, covering, by stage 4, an extensive portion of the inner lining of the blastocoel. Fibronectin-positive material is still present in a fibrillar form in stage 3 blastocysts, but is generally reduced to thin strands by stage 4. These results indicate that fibronectin is independent of the mouse blastocyst basement membrane, but may play a transient role in cell adhesion during its deposition. In addition, the results suggest that the ICM plays a major role in the production of collagen-IV and laminin, while the basal surface of TE cells is the primary site of basement membrane assembly.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Wiley
Loading ...
Support Center