Contacts between pigmented retina epithelial cells in culture.
The behaviour of primary cultures of dissociated embryonic chick pigmented retina epithelial (PRE) cells has been investigated. Isolated PRE cells have a mean speed of locomotion of 7-16 mum/h. Collisions between the cells normally result in the development of stable contacts between the cells involved. This leads to a gradual reduction in the number of isolated cells and an increase in the number of cells incorporated into islands. Ultrastructural observations of islands of cells after 24 h in culture show that junctional complexes are present between the cells. These complexes consist of 2 components: (a) an apically situated region of focal tight junctions and/or gap junctions, and (b) a more ventrally located zonula adhaerens with associated cytoplasmic filaments forming a band running completely around the periphery of each cell. The intermembrane gap in the region of the zonula is 6-0-12-0 nm. The junctional complexes become more differentiated with time and after 48 h in culture consist of an extensive region of tight junctions and/or gap junctions and a more specialized zonula adhaerens. It is suggested that the development of junctional complexes may be responsible for the stable contacts that the cells display in culture.
D000818:Animals; D002465:Cell Movement; D002478:Cells, Cultured; D002642:Chick Embryo; D003594:Cytoplasmic Granules / Q000648:ultrastructure; D004721:Endoplasmic Reticulum / Q000648:ultrastructure; D006056:Golgi Apparatus / Q000648:ultrastructure; D007365:Intercellular Junctions / Q000648:ultrastructure*; D010857:Pigment Epithelium of Eye / Q000166:cytology / Q000648:ultrastructure*